| // SPDX-License-Identifier: GPL-2.0-only |
| /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com |
| */ |
| #include <linux/bpf.h> |
| #include <linux/bpf-cgroup.h> |
| #include <linux/bpf_trace.h> |
| #include <linux/bpf_lirc.h> |
| #include <linux/bpf_verifier.h> |
| #include <linux/bsearch.h> |
| #include <linux/btf.h> |
| #include <linux/syscalls.h> |
| #include <linux/slab.h> |
| #include <linux/sched/signal.h> |
| #include <linux/vmalloc.h> |
| #include <linux/mmzone.h> |
| #include <linux/anon_inodes.h> |
| #include <linux/fdtable.h> |
| #include <linux/file.h> |
| #include <linux/fs.h> |
| #include <linux/license.h> |
| #include <linux/filter.h> |
| #include <linux/kernel.h> |
| #include <linux/idr.h> |
| #include <linux/cred.h> |
| #include <linux/timekeeping.h> |
| #include <linux/ctype.h> |
| #include <linux/nospec.h> |
| #include <linux/audit.h> |
| #include <uapi/linux/btf.h> |
| #include <linux/pgtable.h> |
| #include <linux/bpf_lsm.h> |
| #include <linux/poll.h> |
| #include <linux/sort.h> |
| #include <linux/bpf-netns.h> |
| #include <linux/rcupdate_trace.h> |
| #include <linux/memcontrol.h> |
| #include <linux/trace_events.h> |
| |
| #include <net/netfilter/nf_bpf_link.h> |
| #include <net/netkit.h> |
| #include <net/tcx.h> |
| |
| #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ |
| (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \ |
| (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) |
| #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY) |
| #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) |
| #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \ |
| IS_FD_HASH(map)) |
| |
| #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY) |
| |
| DEFINE_PER_CPU(int, bpf_prog_active); |
| static DEFINE_IDR(prog_idr); |
| static DEFINE_SPINLOCK(prog_idr_lock); |
| static DEFINE_IDR(map_idr); |
| static DEFINE_SPINLOCK(map_idr_lock); |
| static DEFINE_IDR(link_idr); |
| static DEFINE_SPINLOCK(link_idr_lock); |
| |
| int sysctl_unprivileged_bpf_disabled __read_mostly = |
| IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0; |
| |
| static const struct bpf_map_ops * const bpf_map_types[] = { |
| #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) |
| #define BPF_MAP_TYPE(_id, _ops) \ |
| [_id] = &_ops, |
| #define BPF_LINK_TYPE(_id, _name) |
| #include <linux/bpf_types.h> |
| #undef BPF_PROG_TYPE |
| #undef BPF_MAP_TYPE |
| #undef BPF_LINK_TYPE |
| }; |
| |
| /* |
| * If we're handed a bigger struct than we know of, ensure all the unknown bits |
| * are 0 - i.e. new user-space does not rely on any kernel feature extensions |
| * we don't know about yet. |
| * |
| * There is a ToCToU between this function call and the following |
| * copy_from_user() call. However, this is not a concern since this function is |
| * meant to be a future-proofing of bits. |
| */ |
| int bpf_check_uarg_tail_zero(bpfptr_t uaddr, |
| size_t expected_size, |
| size_t actual_size) |
| { |
| int res; |
| |
| if (unlikely(actual_size > PAGE_SIZE)) /* silly large */ |
| return -E2BIG; |
| |
| if (actual_size <= expected_size) |
| return 0; |
| |
| if (uaddr.is_kernel) |
| res = memchr_inv(uaddr.kernel + expected_size, 0, |
| actual_size - expected_size) == NULL; |
| else |
| res = check_zeroed_user(uaddr.user + expected_size, |
| actual_size - expected_size); |
| if (res < 0) |
| return res; |
| return res ? 0 : -E2BIG; |
| } |
| |
| const struct bpf_map_ops bpf_map_offload_ops = { |
| .map_meta_equal = bpf_map_meta_equal, |
| .map_alloc = bpf_map_offload_map_alloc, |
| .map_free = bpf_map_offload_map_free, |
| .map_check_btf = map_check_no_btf, |
| .map_mem_usage = bpf_map_offload_map_mem_usage, |
| }; |
| |
| static void bpf_map_write_active_inc(struct bpf_map *map) |
| { |
| atomic64_inc(&map->writecnt); |
| } |
| |
| static void bpf_map_write_active_dec(struct bpf_map *map) |
| { |
| atomic64_dec(&map->writecnt); |
| } |
| |
| bool bpf_map_write_active(const struct bpf_map *map) |
| { |
| return atomic64_read(&map->writecnt) != 0; |
| } |
| |
| static u32 bpf_map_value_size(const struct bpf_map *map) |
| { |
| if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || |
| map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || |
| map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || |
| map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) |
| return round_up(map->value_size, 8) * num_possible_cpus(); |
| else if (IS_FD_MAP(map)) |
| return sizeof(u32); |
| else |
| return map->value_size; |
| } |
| |
| static void maybe_wait_bpf_programs(struct bpf_map *map) |
| { |
| /* Wait for any running non-sleepable BPF programs to complete so that |
| * userspace, when we return to it, knows that all non-sleepable |
| * programs that could be running use the new map value. For sleepable |
| * BPF programs, synchronize_rcu_tasks_trace() should be used to wait |
| * for the completions of these programs, but considering the waiting |
| * time can be very long and userspace may think it will hang forever, |
| * so don't handle sleepable BPF programs now. |
| */ |
| if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS || |
| map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) |
| synchronize_rcu(); |
| } |
| |
| static int bpf_map_update_value(struct bpf_map *map, struct file *map_file, |
| void *key, void *value, __u64 flags) |
| { |
| int err; |
| |
| /* Need to create a kthread, thus must support schedule */ |
| if (bpf_map_is_offloaded(map)) { |
| return bpf_map_offload_update_elem(map, key, value, flags); |
| } else if (map->map_type == BPF_MAP_TYPE_CPUMAP || |
| map->map_type == BPF_MAP_TYPE_ARENA || |
| map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { |
| return map->ops->map_update_elem(map, key, value, flags); |
| } else if (map->map_type == BPF_MAP_TYPE_SOCKHASH || |
| map->map_type == BPF_MAP_TYPE_SOCKMAP) { |
| return sock_map_update_elem_sys(map, key, value, flags); |
| } else if (IS_FD_PROG_ARRAY(map)) { |
| return bpf_fd_array_map_update_elem(map, map_file, key, value, |
| flags); |
| } |
| |
| bpf_disable_instrumentation(); |
| if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || |
| map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { |
| err = bpf_percpu_hash_update(map, key, value, flags); |
| } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { |
| err = bpf_percpu_array_update(map, key, value, flags); |
| } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { |
| err = bpf_percpu_cgroup_storage_update(map, key, value, |
| flags); |
| } else if (IS_FD_ARRAY(map)) { |
| err = bpf_fd_array_map_update_elem(map, map_file, key, value, |
| flags); |
| } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { |
| err = bpf_fd_htab_map_update_elem(map, map_file, key, value, |
| flags); |
| } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { |
| /* rcu_read_lock() is not needed */ |
| err = bpf_fd_reuseport_array_update_elem(map, key, value, |
| flags); |
| } else if (map->map_type == BPF_MAP_TYPE_QUEUE || |
| map->map_type == BPF_MAP_TYPE_STACK || |
| map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { |
| err = map->ops->map_push_elem(map, value, flags); |
| } else { |
| rcu_read_lock(); |
| err = map->ops->map_update_elem(map, key, value, flags); |
| rcu_read_unlock(); |
| } |
| bpf_enable_instrumentation(); |
| |
| return err; |
| } |
| |
| static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value, |
| __u64 flags) |
| { |
| void *ptr; |
| int err; |
| |
| if (bpf_map_is_offloaded(map)) |
| return bpf_map_offload_lookup_elem(map, key, value); |
| |
| bpf_disable_instrumentation(); |
| if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || |
| map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { |
| err = bpf_percpu_hash_copy(map, key, value); |
| } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { |
| err = bpf_percpu_array_copy(map, key, value); |
| } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { |
| err = bpf_percpu_cgroup_storage_copy(map, key, value); |
| } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { |
| err = bpf_stackmap_copy(map, key, value); |
| } else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) { |
| err = bpf_fd_array_map_lookup_elem(map, key, value); |
| } else if (IS_FD_HASH(map)) { |
| err = bpf_fd_htab_map_lookup_elem(map, key, value); |
| } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { |
| err = bpf_fd_reuseport_array_lookup_elem(map, key, value); |
| } else if (map->map_type == BPF_MAP_TYPE_QUEUE || |
| map->map_type == BPF_MAP_TYPE_STACK || |
| map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { |
| err = map->ops->map_peek_elem(map, value); |
| } else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { |
| /* struct_ops map requires directly updating "value" */ |
| err = bpf_struct_ops_map_sys_lookup_elem(map, key, value); |
| } else { |
| rcu_read_lock(); |
| if (map->ops->map_lookup_elem_sys_only) |
| ptr = map->ops->map_lookup_elem_sys_only(map, key); |
| else |
| ptr = map->ops->map_lookup_elem(map, key); |
| if (IS_ERR(ptr)) { |
| err = PTR_ERR(ptr); |
| } else if (!ptr) { |
| err = -ENOENT; |
| } else { |
| err = 0; |
| if (flags & BPF_F_LOCK) |
| /* lock 'ptr' and copy everything but lock */ |
| copy_map_value_locked(map, value, ptr, true); |
| else |
| copy_map_value(map, value, ptr); |
| /* mask lock and timer, since value wasn't zero inited */ |
| check_and_init_map_value(map, value); |
| } |
| rcu_read_unlock(); |
| } |
| |
| bpf_enable_instrumentation(); |
| |
| return err; |
| } |
| |
| /* Please, do not use this function outside from the map creation path |
| * (e.g. in map update path) without taking care of setting the active |
| * memory cgroup (see at bpf_map_kmalloc_node() for example). |
| */ |
| static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable) |
| { |
| /* We really just want to fail instead of triggering OOM killer |
| * under memory pressure, therefore we set __GFP_NORETRY to kmalloc, |
| * which is used for lower order allocation requests. |
| * |
| * It has been observed that higher order allocation requests done by |
| * vmalloc with __GFP_NORETRY being set might fail due to not trying |
| * to reclaim memory from the page cache, thus we set |
| * __GFP_RETRY_MAYFAIL to avoid such situations. |
| */ |
| |
| gfp_t gfp = bpf_memcg_flags(__GFP_NOWARN | __GFP_ZERO); |
| unsigned int flags = 0; |
| unsigned long align = 1; |
| void *area; |
| |
| if (size >= SIZE_MAX) |
| return NULL; |
| |
| /* kmalloc()'ed memory can't be mmap()'ed */ |
| if (mmapable) { |
| BUG_ON(!PAGE_ALIGNED(size)); |
| align = SHMLBA; |
| flags = VM_USERMAP; |
| } else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { |
| area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY, |
| numa_node); |
| if (area != NULL) |
| return area; |
| } |
| |
| return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END, |
| gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL, |
| flags, numa_node, __builtin_return_address(0)); |
| } |
| |
| void *bpf_map_area_alloc(u64 size, int numa_node) |
| { |
| return __bpf_map_area_alloc(size, numa_node, false); |
| } |
| |
| void *bpf_map_area_mmapable_alloc(u64 size, int numa_node) |
| { |
| return __bpf_map_area_alloc(size, numa_node, true); |
| } |
| |
| void bpf_map_area_free(void *area) |
| { |
| kvfree(area); |
| } |
| |
| static u32 bpf_map_flags_retain_permanent(u32 flags) |
| { |
| /* Some map creation flags are not tied to the map object but |
| * rather to the map fd instead, so they have no meaning upon |
| * map object inspection since multiple file descriptors with |
| * different (access) properties can exist here. Thus, given |
| * this has zero meaning for the map itself, lets clear these |
| * from here. |
| */ |
| return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY); |
| } |
| |
| void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr) |
| { |
| map->map_type = attr->map_type; |
| map->key_size = attr->key_size; |
| map->value_size = attr->value_size; |
| map->max_entries = attr->max_entries; |
| map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags); |
| map->numa_node = bpf_map_attr_numa_node(attr); |
| map->map_extra = attr->map_extra; |
| } |
| |
| static int bpf_map_alloc_id(struct bpf_map *map) |
| { |
| int id; |
| |
| idr_preload(GFP_KERNEL); |
| spin_lock_bh(&map_idr_lock); |
| id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC); |
| if (id > 0) |
| map->id = id; |
| spin_unlock_bh(&map_idr_lock); |
| idr_preload_end(); |
| |
| if (WARN_ON_ONCE(!id)) |
| return -ENOSPC; |
| |
| return id > 0 ? 0 : id; |
| } |
| |
| void bpf_map_free_id(struct bpf_map *map) |
| { |
| unsigned long flags; |
| |
| /* Offloaded maps are removed from the IDR store when their device |
| * disappears - even if someone holds an fd to them they are unusable, |
| * the memory is gone, all ops will fail; they are simply waiting for |
| * refcnt to drop to be freed. |
| */ |
| if (!map->id) |
| return; |
| |
| spin_lock_irqsave(&map_idr_lock, flags); |
| |
| idr_remove(&map_idr, map->id); |
| map->id = 0; |
| |
| spin_unlock_irqrestore(&map_idr_lock, flags); |
| } |
| |
| #ifdef CONFIG_MEMCG |
| static void bpf_map_save_memcg(struct bpf_map *map) |
| { |
| /* Currently if a map is created by a process belonging to the root |
| * memory cgroup, get_obj_cgroup_from_current() will return NULL. |
| * So we have to check map->objcg for being NULL each time it's |
| * being used. |
| */ |
| if (memcg_bpf_enabled()) |
| map->objcg = get_obj_cgroup_from_current(); |
| } |
| |
| static void bpf_map_release_memcg(struct bpf_map *map) |
| { |
| if (map->objcg) |
| obj_cgroup_put(map->objcg); |
| } |
| |
| static struct mem_cgroup *bpf_map_get_memcg(const struct bpf_map *map) |
| { |
| if (map->objcg) |
| return get_mem_cgroup_from_objcg(map->objcg); |
| |
| return root_mem_cgroup; |
| } |
| |
| void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags, |
| int node) |
| { |
| struct mem_cgroup *memcg, *old_memcg; |
| void *ptr; |
| |
| memcg = bpf_map_get_memcg(map); |
| old_memcg = set_active_memcg(memcg); |
| ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node); |
| set_active_memcg(old_memcg); |
| mem_cgroup_put(memcg); |
| |
| return ptr; |
| } |
| |
| void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags) |
| { |
| struct mem_cgroup *memcg, *old_memcg; |
| void *ptr; |
| |
| memcg = bpf_map_get_memcg(map); |
| old_memcg = set_active_memcg(memcg); |
| ptr = kzalloc(size, flags | __GFP_ACCOUNT); |
| set_active_memcg(old_memcg); |
| mem_cgroup_put(memcg); |
| |
| return ptr; |
| } |
| |
| void *bpf_map_kvcalloc(struct bpf_map *map, size_t n, size_t size, |
| gfp_t flags) |
| { |
| struct mem_cgroup *memcg, *old_memcg; |
| void *ptr; |
| |
| memcg = bpf_map_get_memcg(map); |
| old_memcg = set_active_memcg(memcg); |
| ptr = kvcalloc(n, size, flags | __GFP_ACCOUNT); |
| set_active_memcg(old_memcg); |
| mem_cgroup_put(memcg); |
| |
| return ptr; |
| } |
| |
| void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size, |
| size_t align, gfp_t flags) |
| { |
| struct mem_cgroup *memcg, *old_memcg; |
| void __percpu *ptr; |
| |
| memcg = bpf_map_get_memcg(map); |
| old_memcg = set_active_memcg(memcg); |
| ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT); |
| set_active_memcg(old_memcg); |
| mem_cgroup_put(memcg); |
| |
| return ptr; |
| } |
| |
| #else |
| static void bpf_map_save_memcg(struct bpf_map *map) |
| { |
| } |
| |
| static void bpf_map_release_memcg(struct bpf_map *map) |
| { |
| } |
| #endif |
| |
| int bpf_map_alloc_pages(const struct bpf_map *map, gfp_t gfp, int nid, |
| unsigned long nr_pages, struct page **pages) |
| { |
| unsigned long i, j; |
| struct page *pg; |
| int ret = 0; |
| #ifdef CONFIG_MEMCG |
| struct mem_cgroup *memcg, *old_memcg; |
| |
| memcg = bpf_map_get_memcg(map); |
| old_memcg = set_active_memcg(memcg); |
| #endif |
| for (i = 0; i < nr_pages; i++) { |
| pg = alloc_pages_node(nid, gfp | __GFP_ACCOUNT, 0); |
| |
| if (pg) { |
| pages[i] = pg; |
| continue; |
| } |
| for (j = 0; j < i; j++) |
| __free_page(pages[j]); |
| ret = -ENOMEM; |
| break; |
| } |
| |
| #ifdef CONFIG_MEMCG |
| set_active_memcg(old_memcg); |
| mem_cgroup_put(memcg); |
| #endif |
| return ret; |
| } |
| |
| |
| static int btf_field_cmp(const void *a, const void *b) |
| { |
| const struct btf_field *f1 = a, *f2 = b; |
| |
| if (f1->offset < f2->offset) |
| return -1; |
| else if (f1->offset > f2->offset) |
| return 1; |
| return 0; |
| } |
| |
| struct btf_field *btf_record_find(const struct btf_record *rec, u32 offset, |
| u32 field_mask) |
| { |
| struct btf_field *field; |
| |
| if (IS_ERR_OR_NULL(rec) || !(rec->field_mask & field_mask)) |
| return NULL; |
| field = bsearch(&offset, rec->fields, rec->cnt, sizeof(rec->fields[0]), btf_field_cmp); |
| if (!field || !(field->type & field_mask)) |
| return NULL; |
| return field; |
| } |
| |
| void btf_record_free(struct btf_record *rec) |
| { |
| int i; |
| |
| if (IS_ERR_OR_NULL(rec)) |
| return; |
| for (i = 0; i < rec->cnt; i++) { |
| switch (rec->fields[i].type) { |
| case BPF_KPTR_UNREF: |
| case BPF_KPTR_REF: |
| case BPF_KPTR_PERCPU: |
| if (rec->fields[i].kptr.module) |
| module_put(rec->fields[i].kptr.module); |
| if (btf_is_kernel(rec->fields[i].kptr.btf)) |
| btf_put(rec->fields[i].kptr.btf); |
| break; |
| case BPF_LIST_HEAD: |
| case BPF_LIST_NODE: |
| case BPF_RB_ROOT: |
| case BPF_RB_NODE: |
| case BPF_SPIN_LOCK: |
| case BPF_TIMER: |
| case BPF_REFCOUNT: |
| case BPF_WORKQUEUE: |
| /* Nothing to release */ |
| break; |
| default: |
| WARN_ON_ONCE(1); |
| continue; |
| } |
| } |
| kfree(rec); |
| } |
| |
| void bpf_map_free_record(struct bpf_map *map) |
| { |
| btf_record_free(map->record); |
| map->record = NULL; |
| } |
| |
| struct btf_record *btf_record_dup(const struct btf_record *rec) |
| { |
| const struct btf_field *fields; |
| struct btf_record *new_rec; |
| int ret, size, i; |
| |
| if (IS_ERR_OR_NULL(rec)) |
| return NULL; |
| size = offsetof(struct btf_record, fields[rec->cnt]); |
| new_rec = kmemdup(rec, size, GFP_KERNEL | __GFP_NOWARN); |
| if (!new_rec) |
| return ERR_PTR(-ENOMEM); |
| /* Do a deep copy of the btf_record */ |
| fields = rec->fields; |
| new_rec->cnt = 0; |
| for (i = 0; i < rec->cnt; i++) { |
| switch (fields[i].type) { |
| case BPF_KPTR_UNREF: |
| case BPF_KPTR_REF: |
| case BPF_KPTR_PERCPU: |
| if (btf_is_kernel(fields[i].kptr.btf)) |
| btf_get(fields[i].kptr.btf); |
| if (fields[i].kptr.module && !try_module_get(fields[i].kptr.module)) { |
| ret = -ENXIO; |
| goto free; |
| } |
| break; |
| case BPF_LIST_HEAD: |
| case BPF_LIST_NODE: |
| case BPF_RB_ROOT: |
| case BPF_RB_NODE: |
| case BPF_SPIN_LOCK: |
| case BPF_TIMER: |
| case BPF_REFCOUNT: |
| case BPF_WORKQUEUE: |
| /* Nothing to acquire */ |
| break; |
| default: |
| ret = -EFAULT; |
| WARN_ON_ONCE(1); |
| goto free; |
| } |
| new_rec->cnt++; |
| } |
| return new_rec; |
| free: |
| btf_record_free(new_rec); |
| return ERR_PTR(ret); |
| } |
| |
| bool btf_record_equal(const struct btf_record *rec_a, const struct btf_record *rec_b) |
| { |
| bool a_has_fields = !IS_ERR_OR_NULL(rec_a), b_has_fields = !IS_ERR_OR_NULL(rec_b); |
| int size; |
| |
| if (!a_has_fields && !b_has_fields) |
| return true; |
| if (a_has_fields != b_has_fields) |
| return false; |
| if (rec_a->cnt != rec_b->cnt) |
| return false; |
| size = offsetof(struct btf_record, fields[rec_a->cnt]); |
| /* btf_parse_fields uses kzalloc to allocate a btf_record, so unused |
| * members are zeroed out. So memcmp is safe to do without worrying |
| * about padding/unused fields. |
| * |
| * While spin_lock, timer, and kptr have no relation to map BTF, |
| * list_head metadata is specific to map BTF, the btf and value_rec |
| * members in particular. btf is the map BTF, while value_rec points to |
| * btf_record in that map BTF. |
| * |
| * So while by default, we don't rely on the map BTF (which the records |
| * were parsed from) matching for both records, which is not backwards |
| * compatible, in case list_head is part of it, we implicitly rely on |
| * that by way of depending on memcmp succeeding for it. |
| */ |
| return !memcmp(rec_a, rec_b, size); |
| } |
| |
| void bpf_obj_free_timer(const struct btf_record *rec, void *obj) |
| { |
| if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_TIMER))) |
| return; |
| bpf_timer_cancel_and_free(obj + rec->timer_off); |
| } |
| |
| void bpf_obj_free_workqueue(const struct btf_record *rec, void *obj) |
| { |
| if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_WORKQUEUE))) |
| return; |
| bpf_wq_cancel_and_free(obj + rec->wq_off); |
| } |
| |
| void bpf_obj_free_fields(const struct btf_record *rec, void *obj) |
| { |
| const struct btf_field *fields; |
| int i; |
| |
| if (IS_ERR_OR_NULL(rec)) |
| return; |
| fields = rec->fields; |
| for (i = 0; i < rec->cnt; i++) { |
| struct btf_struct_meta *pointee_struct_meta; |
| const struct btf_field *field = &fields[i]; |
| void *field_ptr = obj + field->offset; |
| void *xchgd_field; |
| |
| switch (fields[i].type) { |
| case BPF_SPIN_LOCK: |
| break; |
| case BPF_TIMER: |
| bpf_timer_cancel_and_free(field_ptr); |
| break; |
| case BPF_WORKQUEUE: |
| bpf_wq_cancel_and_free(field_ptr); |
| break; |
| case BPF_KPTR_UNREF: |
| WRITE_ONCE(*(u64 *)field_ptr, 0); |
| break; |
| case BPF_KPTR_REF: |
| case BPF_KPTR_PERCPU: |
| xchgd_field = (void *)xchg((unsigned long *)field_ptr, 0); |
| if (!xchgd_field) |
| break; |
| |
| if (!btf_is_kernel(field->kptr.btf)) { |
| pointee_struct_meta = btf_find_struct_meta(field->kptr.btf, |
| field->kptr.btf_id); |
| migrate_disable(); |
| __bpf_obj_drop_impl(xchgd_field, pointee_struct_meta ? |
| pointee_struct_meta->record : NULL, |
| fields[i].type == BPF_KPTR_PERCPU); |
| migrate_enable(); |
| } else { |
| field->kptr.dtor(xchgd_field); |
| } |
| break; |
| case BPF_LIST_HEAD: |
| if (WARN_ON_ONCE(rec->spin_lock_off < 0)) |
| continue; |
| bpf_list_head_free(field, field_ptr, obj + rec->spin_lock_off); |
| break; |
| case BPF_RB_ROOT: |
| if (WARN_ON_ONCE(rec->spin_lock_off < 0)) |
| continue; |
| bpf_rb_root_free(field, field_ptr, obj + rec->spin_lock_off); |
| break; |
| case BPF_LIST_NODE: |
| case BPF_RB_NODE: |
| case BPF_REFCOUNT: |
| break; |
| default: |
| WARN_ON_ONCE(1); |
| continue; |
| } |
| } |
| } |
| |
| static void bpf_map_free(struct bpf_map *map) |
| { |
| struct btf_record *rec = map->record; |
| struct btf *btf = map->btf; |
| |
| /* implementation dependent freeing */ |
| map->ops->map_free(map); |
| /* Delay freeing of btf_record for maps, as map_free |
| * callback usually needs access to them. It is better to do it here |
| * than require each callback to do the free itself manually. |
| * |
| * Note that the btf_record stashed in map->inner_map_meta->record was |
| * already freed using the map_free callback for map in map case which |
| * eventually calls bpf_map_free_meta, since inner_map_meta is only a |
| * template bpf_map struct used during verification. |
| */ |
| btf_record_free(rec); |
| /* Delay freeing of btf for maps, as map_free callback may need |
| * struct_meta info which will be freed with btf_put(). |
| */ |
| btf_put(btf); |
| } |
| |
| /* called from workqueue */ |
| static void bpf_map_free_deferred(struct work_struct *work) |
| { |
| struct bpf_map *map = container_of(work, struct bpf_map, work); |
| |
| security_bpf_map_free(map); |
| bpf_map_release_memcg(map); |
| bpf_map_free(map); |
| } |
| |
| static void bpf_map_put_uref(struct bpf_map *map) |
| { |
| if (atomic64_dec_and_test(&map->usercnt)) { |
| if (map->ops->map_release_uref) |
| map->ops->map_release_uref(map); |
| } |
| } |
| |
| static void bpf_map_free_in_work(struct bpf_map *map) |
| { |
| INIT_WORK(&map->work, bpf_map_free_deferred); |
| /* Avoid spawning kworkers, since they all might contend |
| * for the same mutex like slab_mutex. |
| */ |
| queue_work(system_unbound_wq, &map->work); |
| } |
| |
| static void bpf_map_free_rcu_gp(struct rcu_head *rcu) |
| { |
| bpf_map_free_in_work(container_of(rcu, struct bpf_map, rcu)); |
| } |
| |
| static void bpf_map_free_mult_rcu_gp(struct rcu_head *rcu) |
| { |
| if (rcu_trace_implies_rcu_gp()) |
| bpf_map_free_rcu_gp(rcu); |
| else |
| call_rcu(rcu, bpf_map_free_rcu_gp); |
| } |
| |
| /* decrement map refcnt and schedule it for freeing via workqueue |
| * (underlying map implementation ops->map_free() might sleep) |
| */ |
| void bpf_map_put(struct bpf_map *map) |
| { |
| if (atomic64_dec_and_test(&map->refcnt)) { |
| /* bpf_map_free_id() must be called first */ |
| bpf_map_free_id(map); |
| |
| WARN_ON_ONCE(atomic64_read(&map->sleepable_refcnt)); |
| if (READ_ONCE(map->free_after_mult_rcu_gp)) |
| call_rcu_tasks_trace(&map->rcu, bpf_map_free_mult_rcu_gp); |
| else if (READ_ONCE(map->free_after_rcu_gp)) |
| call_rcu(&map->rcu, bpf_map_free_rcu_gp); |
| else |
| bpf_map_free_in_work(map); |
| } |
| } |
| EXPORT_SYMBOL_GPL(bpf_map_put); |
| |
| void bpf_map_put_with_uref(struct bpf_map *map) |
| { |
| bpf_map_put_uref(map); |
| bpf_map_put(map); |
| } |
| |
| static int bpf_map_release(struct inode *inode, struct file *filp) |
| { |
| struct bpf_map *map = filp->private_data; |
| |
| if (map->ops->map_release) |
| map->ops->map_release(map, filp); |
| |
| bpf_map_put_with_uref(map); |
| return 0; |
| } |
| |
| static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f) |
| { |
| fmode_t mode = fd_file(f)->f_mode; |
| |
| /* Our file permissions may have been overridden by global |
| * map permissions facing syscall side. |
| */ |
| if (READ_ONCE(map->frozen)) |
| mode &= ~FMODE_CAN_WRITE; |
| return mode; |
| } |
| |
| #ifdef CONFIG_PROC_FS |
| /* Show the memory usage of a bpf map */ |
| static u64 bpf_map_memory_usage(const struct bpf_map *map) |
| { |
| return map->ops->map_mem_usage(map); |
| } |
| |
| static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) |
| { |
| struct bpf_map *map = filp->private_data; |
| u32 type = 0, jited = 0; |
| |
| if (map_type_contains_progs(map)) { |
| spin_lock(&map->owner.lock); |
| type = map->owner.type; |
| jited = map->owner.jited; |
| spin_unlock(&map->owner.lock); |
| } |
| |
| seq_printf(m, |
| "map_type:\t%u\n" |
| "key_size:\t%u\n" |
| "value_size:\t%u\n" |
| "max_entries:\t%u\n" |
| "map_flags:\t%#x\n" |
| "map_extra:\t%#llx\n" |
| "memlock:\t%llu\n" |
| "map_id:\t%u\n" |
| "frozen:\t%u\n", |
| map->map_type, |
| map->key_size, |
| map->value_size, |
| map->max_entries, |
| map->map_flags, |
| (unsigned long long)map->map_extra, |
| bpf_map_memory_usage(map), |
| map->id, |
| READ_ONCE(map->frozen)); |
| if (type) { |
| seq_printf(m, "owner_prog_type:\t%u\n", type); |
| seq_printf(m, "owner_jited:\t%u\n", jited); |
| } |
| } |
| #endif |
| |
| static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz, |
| loff_t *ppos) |
| { |
| /* We need this handler such that alloc_file() enables |
| * f_mode with FMODE_CAN_READ. |
| */ |
| return -EINVAL; |
| } |
| |
| static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf, |
| size_t siz, loff_t *ppos) |
| { |
| /* We need this handler such that alloc_file() enables |
| * f_mode with FMODE_CAN_WRITE. |
| */ |
| return -EINVAL; |
| } |
| |
| /* called for any extra memory-mapped regions (except initial) */ |
| static void bpf_map_mmap_open(struct vm_area_struct *vma) |
| { |
| struct bpf_map *map = vma->vm_file->private_data; |
| |
| if (vma->vm_flags & VM_MAYWRITE) |
| bpf_map_write_active_inc(map); |
| } |
| |
| /* called for all unmapped memory region (including initial) */ |
| static void bpf_map_mmap_close(struct vm_area_struct *vma) |
| { |
| struct bpf_map *map = vma->vm_file->private_data; |
| |
| if (vma->vm_flags & VM_MAYWRITE) |
| bpf_map_write_active_dec(map); |
| } |
| |
| static const struct vm_operations_struct bpf_map_default_vmops = { |
| .open = bpf_map_mmap_open, |
| .close = bpf_map_mmap_close, |
| }; |
| |
| static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma) |
| { |
| struct bpf_map *map = filp->private_data; |
| int err; |
| |
| if (!map->ops->map_mmap || !IS_ERR_OR_NULL(map->record)) |
| return -ENOTSUPP; |
| |
| if (!(vma->vm_flags & VM_SHARED)) |
| return -EINVAL; |
| |
| mutex_lock(&map->freeze_mutex); |
| |
| if (vma->vm_flags & VM_WRITE) { |
| if (map->frozen) { |
| err = -EPERM; |
| goto out; |
| } |
| /* map is meant to be read-only, so do not allow mapping as |
| * writable, because it's possible to leak a writable page |
| * reference and allows user-space to still modify it after |
| * freezing, while verifier will assume contents do not change |
| */ |
| if (map->map_flags & BPF_F_RDONLY_PROG) { |
| err = -EACCES; |
| goto out; |
| } |
| } |
| |
| /* set default open/close callbacks */ |
| vma->vm_ops = &bpf_map_default_vmops; |
| vma->vm_private_data = map; |
| vm_flags_clear(vma, VM_MAYEXEC); |
| if (!(vma->vm_flags & VM_WRITE)) |
| /* disallow re-mapping with PROT_WRITE */ |
| vm_flags_clear(vma, VM_MAYWRITE); |
| |
| err = map->ops->map_mmap(map, vma); |
| if (err) |
| goto out; |
| |
| if (vma->vm_flags & VM_MAYWRITE) |
| bpf_map_write_active_inc(map); |
| out: |
| mutex_unlock(&map->freeze_mutex); |
| return err; |
| } |
| |
| static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts) |
| { |
| struct bpf_map *map = filp->private_data; |
| |
| if (map->ops->map_poll) |
| return map->ops->map_poll(map, filp, pts); |
| |
| return EPOLLERR; |
| } |
| |
| static unsigned long bpf_get_unmapped_area(struct file *filp, unsigned long addr, |
| unsigned long len, unsigned long pgoff, |
| unsigned long flags) |
| { |
| struct bpf_map *map = filp->private_data; |
| |
| if (map->ops->map_get_unmapped_area) |
| return map->ops->map_get_unmapped_area(filp, addr, len, pgoff, flags); |
| #ifdef CONFIG_MMU |
| return mm_get_unmapped_area(current->mm, filp, addr, len, pgoff, flags); |
| #else |
| return addr; |
| #endif |
| } |
| |
| const struct file_operations bpf_map_fops = { |
| #ifdef CONFIG_PROC_FS |
| .show_fdinfo = bpf_map_show_fdinfo, |
| #endif |
| .release = bpf_map_release, |
| .read = bpf_dummy_read, |
| .write = bpf_dummy_write, |
| .mmap = bpf_map_mmap, |
| .poll = bpf_map_poll, |
| .get_unmapped_area = bpf_get_unmapped_area, |
| }; |
| |
| int bpf_map_new_fd(struct bpf_map *map, int flags) |
| { |
| int ret; |
| |
| ret = security_bpf_map(map, OPEN_FMODE(flags)); |
| if (ret < 0) |
| return ret; |
| |
| return anon_inode_getfd("bpf-map", &bpf_map_fops, map, |
| flags | O_CLOEXEC); |
| } |
| |
| int bpf_get_file_flag(int flags) |
| { |
| if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY)) |
| return -EINVAL; |
| if (flags & BPF_F_RDONLY) |
| return O_RDONLY; |
| if (flags & BPF_F_WRONLY) |
| return O_WRONLY; |
| return O_RDWR; |
| } |
| |
| /* helper macro to check that unused fields 'union bpf_attr' are zero */ |
| #define CHECK_ATTR(CMD) \ |
| memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ |
| sizeof(attr->CMD##_LAST_FIELD), 0, \ |
| sizeof(*attr) - \ |
| offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ |
| sizeof(attr->CMD##_LAST_FIELD)) != NULL |
| |
| /* dst and src must have at least "size" number of bytes. |
| * Return strlen on success and < 0 on error. |
| */ |
| int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size) |
| { |
| const char *end = src + size; |
| const char *orig_src = src; |
| |
| memset(dst, 0, size); |
| /* Copy all isalnum(), '_' and '.' chars. */ |
| while (src < end && *src) { |
| if (!isalnum(*src) && |
| *src != '_' && *src != '.') |
| return -EINVAL; |
| *dst++ = *src++; |
| } |
| |
| /* No '\0' found in "size" number of bytes */ |
| if (src == end) |
| return -EINVAL; |
| |
| return src - orig_src; |
| } |
| |
| int map_check_no_btf(const struct bpf_map *map, |
| const struct btf *btf, |
| const struct btf_type *key_type, |
| const struct btf_type *value_type) |
| { |
| return -ENOTSUPP; |
| } |
| |
| static int map_check_btf(struct bpf_map *map, struct bpf_token *token, |
| const struct btf *btf, u32 btf_key_id, u32 btf_value_id) |
| { |
| const struct btf_type *key_type, *value_type; |
| u32 key_size, value_size; |
| int ret = 0; |
| |
| /* Some maps allow key to be unspecified. */ |
| if (btf_key_id) { |
| key_type = btf_type_id_size(btf, &btf_key_id, &key_size); |
| if (!key_type || key_size != map->key_size) |
| return -EINVAL; |
| } else { |
| key_type = btf_type_by_id(btf, 0); |
| if (!map->ops->map_check_btf) |
| return -EINVAL; |
| } |
| |
| value_type = btf_type_id_size(btf, &btf_value_id, &value_size); |
| if (!value_type || value_size != map->value_size) |
| return -EINVAL; |
| |
| map->record = btf_parse_fields(btf, value_type, |
| BPF_SPIN_LOCK | BPF_TIMER | BPF_KPTR | BPF_LIST_HEAD | |
| BPF_RB_ROOT | BPF_REFCOUNT | BPF_WORKQUEUE, |
| map->value_size); |
| if (!IS_ERR_OR_NULL(map->record)) { |
| int i; |
| |
| if (!bpf_token_capable(token, CAP_BPF)) { |
| ret = -EPERM; |
| goto free_map_tab; |
| } |
| if (map->map_flags & (BPF_F_RDONLY_PROG | BPF_F_WRONLY_PROG)) { |
| ret = -EACCES; |
| goto free_map_tab; |
| } |
| for (i = 0; i < sizeof(map->record->field_mask) * 8; i++) { |
| switch (map->record->field_mask & (1 << i)) { |
| case 0: |
| continue; |
| case BPF_SPIN_LOCK: |
| if (map->map_type != BPF_MAP_TYPE_HASH && |
| map->map_type != BPF_MAP_TYPE_ARRAY && |
| map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && |
| map->map_type != BPF_MAP_TYPE_SK_STORAGE && |
| map->map_type != BPF_MAP_TYPE_INODE_STORAGE && |
| map->map_type != BPF_MAP_TYPE_TASK_STORAGE && |
| map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) { |
| ret = -EOPNOTSUPP; |
| goto free_map_tab; |
| } |
| break; |
| case BPF_TIMER: |
| case BPF_WORKQUEUE: |
| if (map->map_type != BPF_MAP_TYPE_HASH && |
| map->map_type != BPF_MAP_TYPE_LRU_HASH && |
| map->map_type != BPF_MAP_TYPE_ARRAY) { |
| ret = -EOPNOTSUPP; |
| goto free_map_tab; |
| } |
| break; |
| case BPF_KPTR_UNREF: |
| case BPF_KPTR_REF: |
| case BPF_KPTR_PERCPU: |
| case BPF_REFCOUNT: |
| if (map->map_type != BPF_MAP_TYPE_HASH && |
| map->map_type != BPF_MAP_TYPE_PERCPU_HASH && |
| map->map_type != BPF_MAP_TYPE_LRU_HASH && |
| map->map_type != BPF_MAP_TYPE_LRU_PERCPU_HASH && |
| map->map_type != BPF_MAP_TYPE_ARRAY && |
| map->map_type != BPF_MAP_TYPE_PERCPU_ARRAY && |
| map->map_type != BPF_MAP_TYPE_SK_STORAGE && |
| map->map_type != BPF_MAP_TYPE_INODE_STORAGE && |
| map->map_type != BPF_MAP_TYPE_TASK_STORAGE && |
| map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) { |
| ret = -EOPNOTSUPP; |
| goto free_map_tab; |
| } |
| break; |
| case BPF_LIST_HEAD: |
| case BPF_RB_ROOT: |
| if (map->map_type != BPF_MAP_TYPE_HASH && |
| map->map_type != BPF_MAP_TYPE_LRU_HASH && |
| map->map_type != BPF_MAP_TYPE_ARRAY) { |
| ret = -EOPNOTSUPP; |
| goto free_map_tab; |
| } |
| break; |
| default: |
| /* Fail if map_type checks are missing for a field type */ |
| ret = -EOPNOTSUPP; |
| goto free_map_tab; |
| } |
| } |
| } |
| |
| ret = btf_check_and_fixup_fields(btf, map->record); |
| if (ret < 0) |
| goto free_map_tab; |
| |
| if (map->ops->map_check_btf) { |
| ret = map->ops->map_check_btf(map, btf, key_type, value_type); |
| if (ret < 0) |
| goto free_map_tab; |
| } |
| |
| return ret; |
| free_map_tab: |
| bpf_map_free_record(map); |
| return ret; |
| } |
| |
| static bool bpf_net_capable(void) |
| { |
| return capable(CAP_NET_ADMIN) || capable(CAP_SYS_ADMIN); |
| } |
| |
| #define BPF_MAP_CREATE_LAST_FIELD map_token_fd |
| /* called via syscall */ |
| static int map_create(union bpf_attr *attr) |
| { |
| const struct bpf_map_ops *ops; |
| struct bpf_token *token = NULL; |
| int numa_node = bpf_map_attr_numa_node(attr); |
| u32 map_type = attr->map_type; |
| struct bpf_map *map; |
| bool token_flag; |
| int f_flags; |
| int err; |
| |
| err = CHECK_ATTR(BPF_MAP_CREATE); |
| if (err) |
| return -EINVAL; |
| |
| /* check BPF_F_TOKEN_FD flag, remember if it's set, and then clear it |
| * to avoid per-map type checks tripping on unknown flag |
| */ |
| token_flag = attr->map_flags & BPF_F_TOKEN_FD; |
| attr->map_flags &= ~BPF_F_TOKEN_FD; |
| |
| if (attr->btf_vmlinux_value_type_id) { |
| if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS || |
| attr->btf_key_type_id || attr->btf_value_type_id) |
| return -EINVAL; |
| } else if (attr->btf_key_type_id && !attr->btf_value_type_id) { |
| return -EINVAL; |
| } |
| |
| if (attr->map_type != BPF_MAP_TYPE_BLOOM_FILTER && |
| attr->map_type != BPF_MAP_TYPE_ARENA && |
| attr->map_extra != 0) |
| return -EINVAL; |
| |
| f_flags = bpf_get_file_flag(attr->map_flags); |
| if (f_flags < 0) |
| return f_flags; |
| |
| if (numa_node != NUMA_NO_NODE && |
| ((unsigned int)numa_node >= nr_node_ids || |
| !node_online(numa_node))) |
| return -EINVAL; |
| |
| /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ |
| map_type = attr->map_type; |
| if (map_type >= ARRAY_SIZE(bpf_map_types)) |
| return -EINVAL; |
| map_type = array_index_nospec(map_type, ARRAY_SIZE(bpf_map_types)); |
| ops = bpf_map_types[map_type]; |
| if (!ops) |
| return -EINVAL; |
| |
| if (ops->map_alloc_check) { |
| err = ops->map_alloc_check(attr); |
| if (err) |
| return err; |
| } |
| if (attr->map_ifindex) |
| ops = &bpf_map_offload_ops; |
| if (!ops->map_mem_usage) |
| return -EINVAL; |
| |
| if (token_flag) { |
| token = bpf_token_get_from_fd(attr->map_token_fd); |
| if (IS_ERR(token)) |
| return PTR_ERR(token); |
| |
| /* if current token doesn't grant map creation permissions, |
| * then we can't use this token, so ignore it and rely on |
| * system-wide capabilities checks |
| */ |
| if (!bpf_token_allow_cmd(token, BPF_MAP_CREATE) || |
| !bpf_token_allow_map_type(token, attr->map_type)) { |
| bpf_token_put(token); |
| token = NULL; |
| } |
| } |
| |
| err = -EPERM; |
| |
| /* Intent here is for unprivileged_bpf_disabled to block BPF map |
| * creation for unprivileged users; other actions depend |
| * on fd availability and access to bpffs, so are dependent on |
| * object creation success. Even with unprivileged BPF disabled, |
| * capability checks are still carried out. |
| */ |
| if (sysctl_unprivileged_bpf_disabled && !bpf_token_capable(token, CAP_BPF)) |
| goto put_token; |
| |
| /* check privileged map type permissions */ |
| switch (map_type) { |
| case BPF_MAP_TYPE_ARRAY: |
| case BPF_MAP_TYPE_PERCPU_ARRAY: |
| case BPF_MAP_TYPE_PROG_ARRAY: |
| case BPF_MAP_TYPE_PERF_EVENT_ARRAY: |
| case BPF_MAP_TYPE_CGROUP_ARRAY: |
| case BPF_MAP_TYPE_ARRAY_OF_MAPS: |
| case BPF_MAP_TYPE_HASH: |
| case BPF_MAP_TYPE_PERCPU_HASH: |
| case BPF_MAP_TYPE_HASH_OF_MAPS: |
| case BPF_MAP_TYPE_RINGBUF: |
| case BPF_MAP_TYPE_USER_RINGBUF: |
| case BPF_MAP_TYPE_CGROUP_STORAGE: |
| case BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE: |
| /* unprivileged */ |
| break; |
| case BPF_MAP_TYPE_SK_STORAGE: |
| case BPF_MAP_TYPE_INODE_STORAGE: |
| case BPF_MAP_TYPE_TASK_STORAGE: |
| case BPF_MAP_TYPE_CGRP_STORAGE: |
| case BPF_MAP_TYPE_BLOOM_FILTER: |
| case BPF_MAP_TYPE_LPM_TRIE: |
| case BPF_MAP_TYPE_REUSEPORT_SOCKARRAY: |
| case BPF_MAP_TYPE_STACK_TRACE: |
| case BPF_MAP_TYPE_QUEUE: |
| case BPF_MAP_TYPE_STACK: |
| case BPF_MAP_TYPE_LRU_HASH: |
| case BPF_MAP_TYPE_LRU_PERCPU_HASH: |
| case BPF_MAP_TYPE_STRUCT_OPS: |
| case BPF_MAP_TYPE_CPUMAP: |
| case BPF_MAP_TYPE_ARENA: |
| if (!bpf_token_capable(token, CAP_BPF)) |
| goto put_token; |
| break; |
| case BPF_MAP_TYPE_SOCKMAP: |
| case BPF_MAP_TYPE_SOCKHASH: |
| case BPF_MAP_TYPE_DEVMAP: |
| case BPF_MAP_TYPE_DEVMAP_HASH: |
| case BPF_MAP_TYPE_XSKMAP: |
| if (!bpf_token_capable(token, CAP_NET_ADMIN)) |
| goto put_token; |
| break; |
| default: |
| WARN(1, "unsupported map type %d", map_type); |
| goto put_token; |
| } |
| |
| map = ops->map_alloc(attr); |
| if (IS_ERR(map)) { |
| err = PTR_ERR(map); |
| goto put_token; |
| } |
| map->ops = ops; |
| map->map_type = map_type; |
| |
| err = bpf_obj_name_cpy(map->name, attr->map_name, |
| sizeof(attr->map_name)); |
| if (err < 0) |
| goto free_map; |
| |
| atomic64_set(&map->refcnt, 1); |
| atomic64_set(&map->usercnt, 1); |
| mutex_init(&map->freeze_mutex); |
| spin_lock_init(&map->owner.lock); |
| |
| if (attr->btf_key_type_id || attr->btf_value_type_id || |
| /* Even the map's value is a kernel's struct, |
| * the bpf_prog.o must have BTF to begin with |
| * to figure out the corresponding kernel's |
| * counter part. Thus, attr->btf_fd has |
| * to be valid also. |
| */ |
| attr->btf_vmlinux_value_type_id) { |
| struct btf *btf; |
| |
| btf = btf_get_by_fd(attr->btf_fd); |
| if (IS_ERR(btf)) { |
| err = PTR_ERR(btf); |
| goto free_map; |
| } |
| if (btf_is_kernel(btf)) { |
| btf_put(btf); |
| err = -EACCES; |
| goto free_map; |
| } |
| map->btf = btf; |
| |
| if (attr->btf_value_type_id) { |
| err = map_check_btf(map, token, btf, attr->btf_key_type_id, |
| attr->btf_value_type_id); |
| if (err) |
| goto free_map; |
| } |
| |
| map->btf_key_type_id = attr->btf_key_type_id; |
| map->btf_value_type_id = attr->btf_value_type_id; |
| map->btf_vmlinux_value_type_id = |
| attr->btf_vmlinux_value_type_id; |
| } |
| |
| err = security_bpf_map_create(map, attr, token); |
| if (err) |
| goto free_map_sec; |
| |
| err = bpf_map_alloc_id(map); |
| if (err) |
| goto free_map_sec; |
| |
| bpf_map_save_memcg(map); |
| bpf_token_put(token); |
| |
| err = bpf_map_new_fd(map, f_flags); |
| if (err < 0) { |
| /* failed to allocate fd. |
| * bpf_map_put_with_uref() is needed because the above |
| * bpf_map_alloc_id() has published the map |
| * to the userspace and the userspace may |
| * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID. |
| */ |
| bpf_map_put_with_uref(map); |
| return err; |
| } |
| |
| return err; |
| |
| free_map_sec: |
| security_bpf_map_free(map); |
| free_map: |
| bpf_map_free(map); |
| put_token: |
| bpf_token_put(token); |
| return err; |
| } |
| |
| void bpf_map_inc(struct bpf_map *map) |
| { |
| atomic64_inc(&map->refcnt); |
| } |
| EXPORT_SYMBOL_GPL(bpf_map_inc); |
| |
| void bpf_map_inc_with_uref(struct bpf_map *map) |
| { |
| atomic64_inc(&map->refcnt); |
| atomic64_inc(&map->usercnt); |
| } |
| EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref); |
| |
| struct bpf_map *bpf_map_get(u32 ufd) |
| { |
| CLASS(fd, f)(ufd); |
| struct bpf_map *map = __bpf_map_get(f); |
| |
| if (!IS_ERR(map)) |
| bpf_map_inc(map); |
| |
| return map; |
| } |
| EXPORT_SYMBOL(bpf_map_get); |
| |
| struct bpf_map *bpf_map_get_with_uref(u32 ufd) |
| { |
| CLASS(fd, f)(ufd); |
| struct bpf_map *map = __bpf_map_get(f); |
| |
| if (!IS_ERR(map)) |
| bpf_map_inc_with_uref(map); |
| |
| return map; |
| } |
| |
| /* map_idr_lock should have been held or the map should have been |
| * protected by rcu read lock. |
| */ |
| struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref) |
| { |
| int refold; |
| |
| refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0); |
| if (!refold) |
| return ERR_PTR(-ENOENT); |
| if (uref) |
| atomic64_inc(&map->usercnt); |
| |
| return map; |
| } |
| |
| struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map) |
| { |
| spin_lock_bh(&map_idr_lock); |
| map = __bpf_map_inc_not_zero(map, false); |
| spin_unlock_bh(&map_idr_lock); |
| |
| return map; |
| } |
| EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero); |
| |
| int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) |
| { |
| return -ENOTSUPP; |
| } |
| |
| static void *__bpf_copy_key(void __user *ukey, u64 key_size) |
| { |
| if (key_size) |
| return vmemdup_user(ukey, key_size); |
| |
| if (ukey) |
| return ERR_PTR(-EINVAL); |
| |
| return NULL; |
| } |
| |
| static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size) |
| { |
| if (key_size) |
| return kvmemdup_bpfptr(ukey, key_size); |
| |
| if (!bpfptr_is_null(ukey)) |
| return ERR_PTR(-EINVAL); |
| |
| return NULL; |
| } |
| |
| /* last field in 'union bpf_attr' used by this command */ |
| #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags |
| |
| static int map_lookup_elem(union bpf_attr *attr) |
| { |
| void __user *ukey = u64_to_user_ptr(attr->key); |
| void __user *uvalue = u64_to_user_ptr(attr->value); |
| struct bpf_map *map; |
| void *key, *value; |
| u32 value_size; |
| int err; |
| |
| if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) |
| return -EINVAL; |
| |
| if (attr->flags & ~BPF_F_LOCK) |
| return -EINVAL; |
| |
| CLASS(fd, f)(attr->map_fd); |
| map = __bpf_map_get(f); |
| if (IS_ERR(map)) |
| return PTR_ERR(map); |
| if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) |
| return -EPERM; |
| |
| if ((attr->flags & BPF_F_LOCK) && |
| !btf_record_has_field(map->record, BPF_SPIN_LOCK)) |
| return -EINVAL; |
| |
| key = __bpf_copy_key(ukey, map->key_size); |
| if (IS_ERR(key)) |
| return PTR_ERR(key); |
| |
| value_size = bpf_map_value_size(map); |
| |
| err = -ENOMEM; |
| value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); |
| if (!value) |
| goto free_key; |
| |
| if (map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) { |
| if (copy_from_user(value, uvalue, value_size)) |
| err = -EFAULT; |
| else |
| err = bpf_map_copy_value(map, key, value, attr->flags); |
| goto free_value; |
| } |
| |
| err = bpf_map_copy_value(map, key, value, attr->flags); |
| if (err) |
| goto free_value; |
| |
| err = -EFAULT; |
| if (copy_to_user(uvalue, value, value_size) != 0) |
| goto free_value; |
| |
| err = 0; |
| |
| free_value: |
| kvfree(value); |
| free_key: |
| kvfree(key); |
| return err; |
| } |
| |
| |
| #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags |
| |
| static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr) |
| { |
| bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel); |
| bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel); |
| struct bpf_map *map; |
| void *key, *value; |
| u32 value_size; |
| int err; |
| |
| if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) |
| return -EINVAL; |
| |
| CLASS(fd, f)(attr->map_fd); |
| map = __bpf_map_get(f); |
| if (IS_ERR(map)) |
| return PTR_ERR(map); |
| bpf_map_write_active_inc(map); |
| if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { |
| err = -EPERM; |
| goto err_put; |
| } |
| |
| if ((attr->flags & BPF_F_LOCK) && |
| !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { |
| err = -EINVAL; |
| goto err_put; |
| } |
| |
| key = ___bpf_copy_key(ukey, map->key_size); |
| if (IS_ERR(key)) { |
| err = PTR_ERR(key); |
| goto err_put; |
| } |
| |
| value_size = bpf_map_value_size(map); |
| value = kvmemdup_bpfptr(uvalue, value_size); |
| if (IS_ERR(value)) { |
| err = PTR_ERR(value); |
| goto free_key; |
| } |
| |
| err = bpf_map_update_value(map, fd_file(f), key, value, attr->flags); |
| if (!err) |
| maybe_wait_bpf_programs(map); |
| |
| kvfree(value); |
| free_key: |
| kvfree(key); |
| err_put: |
| bpf_map_write_active_dec(map); |
| return err; |
| } |
| |
| #define BPF_MAP_DELETE_ELEM_LAST_FIELD key |
| |
| static int map_delete_elem(union bpf_attr *attr, bpfptr_t uattr) |
| { |
| bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel); |
| struct bpf_map *map; |
| void *key; |
| int err; |
| |
| if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) |
| return -EINVAL; |
| |
| CLASS(fd, f)(attr->map_fd); |
| map = __bpf_map_get(f); |
| if (IS_ERR(map)) |
| return PTR_ERR(map); |
| bpf_map_write_active_inc(map); |
| if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { |
| err = -EPERM; |
| goto err_put; |
| } |
| |
| key = ___bpf_copy_key(ukey, map->key_size); |
| if (IS_ERR(key)) { |
| err = PTR_ERR(key); |
| goto err_put; |
| } |
| |
| if (bpf_map_is_offloaded(map)) { |
| err = bpf_map_offload_delete_elem(map, key); |
| goto out; |
| } else if (IS_FD_PROG_ARRAY(map) || |
| map->map_type == BPF_MAP_TYPE_STRUCT_OPS) { |
| /* These maps require sleepable context */ |
| err = map->ops->map_delete_elem(map, key); |
| goto out; |
| } |
| |
| bpf_disable_instrumentation(); |
| rcu_read_lock(); |
| err = map->ops->map_delete_elem(map, key); |
| rcu_read_unlock(); |
| bpf_enable_instrumentation(); |
| if (!err) |
| maybe_wait_bpf_programs(map); |
| out: |
| kvfree(key); |
| err_put: |
| bpf_map_write_active_dec(map); |
| return err; |
| } |
| |
| /* last field in 'union bpf_attr' used by this command */ |
| #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key |
| |
| static int map_get_next_key(union bpf_attr *attr) |
| { |
| void __user *ukey = u64_to_user_ptr(attr->key); |
| void __user *unext_key = u64_to_user_ptr(attr->next_key); |
| struct bpf_map *map; |
| void *key, *next_key; |
| int err; |
| |
| if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) |
| return -EINVAL; |
| |
| CLASS(fd, f)(attr->map_fd); |
| map = __bpf_map_get(f); |
| if (IS_ERR(map)) |
| return PTR_ERR(map); |
| if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) |
| return -EPERM; |
| |
| if (ukey) { |
| key = __bpf_copy_key(ukey, map->key_size); |
| if (IS_ERR(key)) |
| return PTR_ERR(key); |
| } else { |
| key = NULL; |
| } |
| |
| err = -ENOMEM; |
| next_key = kvmalloc(map->key_size, GFP_USER); |
| if (!next_key) |
| goto free_key; |
| |
| if (bpf_map_is_offloaded(map)) { |
| err = bpf_map_offload_get_next_key(map, key, next_key); |
| goto out; |
| } |
| |
| rcu_read_lock(); |
| err = map->ops->map_get_next_key(map, key, next_key); |
| rcu_read_unlock(); |
| out: |
| if (err) |
| goto free_next_key; |
| |
| err = -EFAULT; |
| if (copy_to_user(unext_key, next_key, map->key_size) != 0) |
| goto free_next_key; |
| |
| err = 0; |
| |
| free_next_key: |
| kvfree(next_key); |
| free_key: |
| kvfree(key); |
| return err; |
| } |
| |
| int generic_map_delete_batch(struct bpf_map *map, |
| const union bpf_attr *attr, |
| union bpf_attr __user *uattr) |
| { |
| void __user *keys = u64_to_user_ptr(attr->batch.keys); |
| u32 cp, max_count; |
| int err = 0; |
| void *key; |
| |
| if (attr->batch.elem_flags & ~BPF_F_LOCK) |
| return -EINVAL; |
| |
| if ((attr->batch.elem_flags & BPF_F_LOCK) && |
| !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { |
| return -EINVAL; |
| } |
| |
| max_count = attr->batch.count; |
| if (!max_count) |
| return 0; |
| |
| if (put_user(0, &uattr->batch.count)) |
| return -EFAULT; |
| |
| key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); |
| if (!key) |
| return -ENOMEM; |
| |
| for (cp = 0; cp < max_count; cp++) { |
| err = -EFAULT; |
| if (copy_from_user(key, keys + cp * map->key_size, |
| map->key_size)) |
| break; |
| |
| if (bpf_map_is_offloaded(map)) { |
| err = bpf_map_offload_delete_elem(map, key); |
| break; |
| } |
| |
| bpf_disable_instrumentation(); |
| rcu_read_lock(); |
| err = map->ops->map_delete_elem(map, key); |
| rcu_read_unlock(); |
| bpf_enable_instrumentation(); |
| if (err) |
| break; |
| cond_resched(); |
| } |
| if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) |
| err = -EFAULT; |
| |
| kvfree(key); |
| |
| return err; |
| } |
| |
| int generic_map_update_batch(struct bpf_map *map, struct file *map_file, |
| const union bpf_attr *attr, |
| union bpf_attr __user *uattr) |
| { |
| void __user *values = u64_to_user_ptr(attr->batch.values); |
| void __user *keys = u64_to_user_ptr(attr->batch.keys); |
| u32 value_size, cp, max_count; |
| void *key, *value; |
| int err = 0; |
| |
| if (attr->batch.elem_flags & ~BPF_F_LOCK) |
| return -EINVAL; |
| |
| if ((attr->batch.elem_flags & BPF_F_LOCK) && |
| !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { |
| return -EINVAL; |
| } |
| |
| value_size = bpf_map_value_size(map); |
| |
| max_count = attr->batch.count; |
| if (!max_count) |
| return 0; |
| |
| if (put_user(0, &uattr->batch.count)) |
| return -EFAULT; |
| |
| key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); |
| if (!key) |
| return -ENOMEM; |
| |
| value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); |
| if (!value) { |
| kvfree(key); |
| return -ENOMEM; |
| } |
| |
| for (cp = 0; cp < max_count; cp++) { |
| err = -EFAULT; |
| if (copy_from_user(key, keys + cp * map->key_size, |
| map->key_size) || |
| copy_from_user(value, values + cp * value_size, value_size)) |
| break; |
| |
| err = bpf_map_update_value(map, map_file, key, value, |
| attr->batch.elem_flags); |
| |
| if (err) |
| break; |
| cond_resched(); |
| } |
| |
| if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp))) |
| err = -EFAULT; |
| |
| kvfree(value); |
| kvfree(key); |
| |
| return err; |
| } |
| |
| #define MAP_LOOKUP_RETRIES 3 |
| |
| int generic_map_lookup_batch(struct bpf_map *map, |
| const union bpf_attr *attr, |
| union bpf_attr __user *uattr) |
| { |
| void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch); |
| void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch); |
| void __user *values = u64_to_user_ptr(attr->batch.values); |
| void __user *keys = u64_to_user_ptr(attr->batch.keys); |
| void *buf, *buf_prevkey, *prev_key, *key, *value; |
| int err, retry = MAP_LOOKUP_RETRIES; |
| u32 value_size, cp, max_count; |
| |
| if (attr->batch.elem_flags & ~BPF_F_LOCK) |
| return -EINVAL; |
| |
| if ((attr->batch.elem_flags & BPF_F_LOCK) && |
| !btf_record_has_field(map->record, BPF_SPIN_LOCK)) |
| return -EINVAL; |
| |
| value_size = bpf_map_value_size(map); |
| |
| max_count = attr->batch.count; |
| if (!max_count) |
| return 0; |
| |
| if (put_user(0, &uattr->batch.count)) |
| return -EFAULT; |
| |
| buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); |
| if (!buf_prevkey) |
| return -ENOMEM; |
| |
| buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN); |
| if (!buf) { |
| kvfree(buf_prevkey); |
| return -ENOMEM; |
| } |
| |
| err = -EFAULT; |
| prev_key = NULL; |
| if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size)) |
| goto free_buf; |
| key = buf; |
| value = key + map->key_size; |
| if (ubatch) |
| prev_key = buf_prevkey; |
| |
| for (cp = 0; cp < max_count;) { |
| rcu_read_lock(); |
| err = map->ops->map_get_next_key(map, prev_key, key); |
| rcu_read_unlock(); |
| if (err) |
| break; |
| err = bpf_map_copy_value(map, key, value, |
| attr->batch.elem_flags); |
| |
| if (err == -ENOENT) { |
| if (retry) { |
| retry--; |
| continue; |
| } |
| err = -EINTR; |
| break; |
| } |
| |
| if (err) |
| goto free_buf; |
| |
| if (copy_to_user(keys + cp * map->key_size, key, |
| map->key_size)) { |
| err = -EFAULT; |
| goto free_buf; |
| } |
| if (copy_to_user(values + cp * value_size, value, value_size)) { |
| err = -EFAULT; |
| goto free_buf; |
| } |
| |
| if (!prev_key) |
| prev_key = buf_prevkey; |
| |
| swap(prev_key, key); |
| retry = MAP_LOOKUP_RETRIES; |
| cp++; |
| cond_resched(); |
| } |
| |
| if (err == -EFAULT) |
| goto free_buf; |
| |
| if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) || |
| (cp && copy_to_user(uobatch, prev_key, map->key_size)))) |
| err = -EFAULT; |
| |
| free_buf: |
| kvfree(buf_prevkey); |
| kvfree(buf); |
| return err; |
| } |
| |
| #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags |
| |
| static int map_lookup_and_delete_elem(union bpf_attr *attr) |
| { |
| void __user *ukey = u64_to_user_ptr(attr->key); |
| void __user *uvalue = u64_to_user_ptr(attr->value); |
| struct bpf_map *map; |
| void *key, *value; |
| u32 value_size; |
| int err; |
| |
| if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM)) |
| return -EINVAL; |
| |
| if (attr->flags & ~BPF_F_LOCK) |
| return -EINVAL; |
| |
| CLASS(fd, f)(attr->map_fd); |
| map = __bpf_map_get(f); |
| if (IS_ERR(map)) |
| return PTR_ERR(map); |
| bpf_map_write_active_inc(map); |
| if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) || |
| !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { |
| err = -EPERM; |
| goto err_put; |
| } |
| |
| if (attr->flags && |
| (map->map_type == BPF_MAP_TYPE_QUEUE || |
| map->map_type == BPF_MAP_TYPE_STACK)) { |
| err = -EINVAL; |
| goto err_put; |
| } |
| |
| if ((attr->flags & BPF_F_LOCK) && |
| !btf_record_has_field(map->record, BPF_SPIN_LOCK)) { |
| err = -EINVAL; |
| goto err_put; |
| } |
| |
| key = __bpf_copy_key(ukey, map->key_size); |
| if (IS_ERR(key)) { |
| err = PTR_ERR(key); |
| goto err_put; |
| } |
| |
| value_size = bpf_map_value_size(map); |
| |
| err = -ENOMEM; |
| value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN); |
| if (!value) |
| goto free_key; |
| |
| err = -ENOTSUPP; |
| if (map->map_type == BPF_MAP_TYPE_QUEUE || |
| map->map_type == BPF_MAP_TYPE_STACK) { |
| err = map->ops->map_pop_elem(map, value); |
| } else if (map->map_type == BPF_MAP_TYPE_HASH || |
| map->map_type == BPF_MAP_TYPE_PERCPU_HASH || |
| map->map_type == BPF_MAP_TYPE_LRU_HASH || |
| map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { |
| if (!bpf_map_is_offloaded(map)) { |
| bpf_disable_instrumentation(); |
| rcu_read_lock(); |
| err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags); |
| rcu_read_unlock(); |
| bpf_enable_instrumentation(); |
| } |
| } |
| |
| if (err) |
| goto free_value; |
| |
| if (copy_to_user(uvalue, value, value_size) != 0) { |
| err = -EFAULT; |
| goto free_value; |
| } |
| |
| err = 0; |
| |
| free_value: |
| kvfree(value); |
| free_key: |
| kvfree(key); |
| err_put: |
| bpf_map_write_active_dec(map); |
| return err; |
| } |
| |
| #define BPF_MAP_FREEZE_LAST_FIELD map_fd |
| |
| static int map_freeze(const union bpf_attr *attr) |
| { |
| int err = 0; |
| struct bpf_map *map; |
| |
| if (CHECK_ATTR(BPF_MAP_FREEZE)) |
| return -EINVAL; |
| |
| CLASS(fd, f)(attr->map_fd); |
| map = __bpf_map_get(f); |
| if (IS_ERR(map)) |
| return PTR_ERR(map); |
| |
| if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS || !IS_ERR_OR_NULL(map->record)) |
| return -ENOTSUPP; |
| |
| if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) |
| return -EPERM; |
| |
| mutex_lock(&map->freeze_mutex); |
| if (bpf_map_write_active(map)) { |
| err = -EBUSY; |
| goto err_put; |
| } |
| if (READ_ONCE(map->frozen)) { |
| err = -EBUSY; |
| goto err_put; |
| } |
| |
| WRITE_ONCE(map->frozen, true); |
| err_put: |
| mutex_unlock(&map->freeze_mutex); |
| return err; |
| } |
| |
| static const struct bpf_prog_ops * const bpf_prog_types[] = { |
| #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \ |
| [_id] = & _name ## _prog_ops, |
| #define BPF_MAP_TYPE(_id, _ops) |
| #define BPF_LINK_TYPE(_id, _name) |
| #include <linux/bpf_types.h> |
| #undef BPF_PROG_TYPE |
| #undef BPF_MAP_TYPE |
| #undef BPF_LINK_TYPE |
| }; |
| |
| static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) |
| { |
| const struct bpf_prog_ops *ops; |
| |
| if (type >= ARRAY_SIZE(bpf_prog_types)) |
| return -EINVAL; |
| type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types)); |
| ops = bpf_prog_types[type]; |
| if (!ops) |
| return -EINVAL; |
| |
| if (!bpf_prog_is_offloaded(prog->aux)) |
| prog->aux->ops = ops; |
| else |
| prog->aux->ops = &bpf_offload_prog_ops; |
| prog->type = type; |
| return 0; |
| } |
| |
| enum bpf_audit { |
| BPF_AUDIT_LOAD, |
| BPF_AUDIT_UNLOAD, |
| BPF_AUDIT_MAX, |
| }; |
| |
| static const char * const bpf_audit_str[BPF_AUDIT_MAX] = { |
| [BPF_AUDIT_LOAD] = "LOAD", |
| [BPF_AUDIT_UNLOAD] = "UNLOAD", |
| }; |
| |
| static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op) |
| { |
| struct audit_context *ctx = NULL; |
| struct audit_buffer *ab; |
| |
| if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX)) |
| return; |
| if (audit_enabled == AUDIT_OFF) |
| return; |
| if (!in_irq() && !irqs_disabled()) |
| ctx = audit_context(); |
| ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF); |
| if (unlikely(!ab)) |
| return; |
| audit_log_format(ab, "prog-id=%u op=%s", |
| prog->aux->id, bpf_audit_str[op]); |
| audit_log_end(ab); |
| } |
| |
| static int bpf_prog_alloc_id(struct bpf_prog *prog) |
| { |
| int id; |
| |
| idr_preload(GFP_KERNEL); |
| spin_lock_bh(&prog_idr_lock); |
| id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); |
| if (id > 0) |
| prog->aux->id = id; |
| spin_unlock_bh(&prog_idr_lock); |
| idr_preload_end(); |
| |
| /* id is in [1, INT_MAX) */ |
| if (WARN_ON_ONCE(!id)) |
| return -ENOSPC; |
| |
| return id > 0 ? 0 : id; |
| } |
| |
| void bpf_prog_free_id(struct bpf_prog *prog) |
| { |
| unsigned long flags; |
| |
| /* cBPF to eBPF migrations are currently not in the idr store. |
| * Offloaded programs are removed from the store when their device |
| * disappears - even if someone grabs an fd to them they are unusable, |
| * simply waiting for refcnt to drop to be freed. |
| */ |
| if (!prog->aux->id) |
| return; |
| |
| spin_lock_irqsave(&prog_idr_lock, flags); |
| idr_remove(&prog_idr, prog->aux->id); |
| prog->aux->id = 0; |
| spin_unlock_irqrestore(&prog_idr_lock, flags); |
| } |
| |
| static void __bpf_prog_put_rcu(struct rcu_head *rcu) |
| { |
| struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); |
| |
| kvfree(aux->func_info); |
| kfree(aux->func_info_aux); |
| free_uid(aux->user); |
| security_bpf_prog_free(aux->prog); |
| bpf_prog_free(aux->prog); |
| } |
| |
| static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred) |
| { |
| bpf_prog_kallsyms_del_all(prog); |
| btf_put(prog->aux->btf); |
| module_put(prog->aux->mod); |
| kvfree(prog->aux->jited_linfo); |
| kvfree(prog->aux->linfo); |
| kfree(prog->aux->kfunc_tab); |
| if (prog->aux->attach_btf) |
| btf_put(prog->aux->attach_btf); |
| |
| if (deferred) { |
| if (prog->sleepable) |
| call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu); |
| else |
| call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); |
| } else { |
| __bpf_prog_put_rcu(&prog->aux->rcu); |
| } |
| } |
| |
| static void bpf_prog_put_deferred(struct work_struct *work) |
| { |
| struct bpf_prog_aux *aux; |
| struct bpf_prog *prog; |
| |
| aux = container_of(work, struct bpf_prog_aux, work); |
| prog = aux->prog; |
| perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); |
| bpf_audit_prog(prog, BPF_AUDIT_UNLOAD); |
| bpf_prog_free_id(prog); |
| __bpf_prog_put_noref(prog, true); |
| } |
| |
| static void __bpf_prog_put(struct bpf_prog *prog) |
| { |
| struct bpf_prog_aux *aux = prog->aux; |
| |
| if (atomic64_dec_and_test(&aux->refcnt)) { |
| if (in_irq() || irqs_disabled()) { |
| INIT_WORK(&aux->work, bpf_prog_put_deferred); |
| schedule_work(&aux->work); |
| } else { |
| bpf_prog_put_deferred(&aux->work); |
| } |
| } |
| } |
| |
| void bpf_prog_put(struct bpf_prog *prog) |
| { |
| __bpf_prog_put(prog); |
| } |
| EXPORT_SYMBOL_GPL(bpf_prog_put); |
| |
| static int bpf_prog_release(struct inode *inode, struct file *filp) |
| { |
| struct bpf_prog *prog = filp->private_data; |
| |
| bpf_prog_put(prog); |
| return 0; |
| } |
| |
| struct bpf_prog_kstats { |
| u64 nsecs; |
| u64 cnt; |
| u64 misses; |
| }; |
| |
| void notrace bpf_prog_inc_misses_counter(struct bpf_prog *prog) |
| { |
| struct bpf_prog_stats *stats; |
| unsigned int flags; |
| |
| stats = this_cpu_ptr(prog->stats); |
| flags = u64_stats_update_begin_irqsave(&stats->syncp); |
| u64_stats_inc(&stats->misses); |
| u64_stats_update_end_irqrestore(&stats->syncp, flags); |
| } |
| |
| static void bpf_prog_get_stats(const struct bpf_prog *prog, |
| struct bpf_prog_kstats *stats) |
| { |
| u64 nsecs = 0, cnt = 0, misses = 0; |
| int cpu; |
| |
| for_each_possible_cpu(cpu) { |
| const struct bpf_prog_stats *st; |
| unsigned int start; |
| u64 tnsecs, tcnt, tmisses; |
| |
| st = per_cpu_ptr(prog->stats, cpu); |
| do { |
| start = u64_stats_fetch_begin(&st->syncp); |
| tnsecs = u64_stats_read(&st->nsecs); |
| tcnt = u64_stats_read(&st->cnt); |
| tmisses = u64_stats_read(&st->misses); |
| } while (u64_stats_fetch_retry(&st->syncp, start)); |
| nsecs += tnsecs; |
| cnt += tcnt; |
| misses += tmisses; |
| } |
| stats->nsecs = nsecs; |
| stats->cnt = cnt; |
| stats->misses = misses; |
| } |
| |
| #ifdef CONFIG_PROC_FS |
| static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) |
| { |
| const struct bpf_prog *prog = filp->private_data; |
| char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; |
| struct bpf_prog_kstats stats; |
| |
| bpf_prog_get_stats(prog, &stats); |
| bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); |
| seq_printf(m, |
| "prog_type:\t%u\n" |
| "prog_jited:\t%u\n" |
| "prog_tag:\t%s\n" |
| "memlock:\t%llu\n" |
| "prog_id:\t%u\n" |
| "run_time_ns:\t%llu\n" |
| "run_cnt:\t%llu\n" |
| "recursion_misses:\t%llu\n" |
| "verified_insns:\t%u\n", |
| prog->type, |
| prog->jited, |
| prog_tag, |
| prog->pages * 1ULL << PAGE_SHIFT, |
| prog->aux->id, |
| stats.nsecs, |
| stats.cnt, |
| stats.misses, |
| prog->aux->verified_insns); |
| } |
| #endif |
| |
| const struct file_operations bpf_prog_fops = { |
| #ifdef CONFIG_PROC_FS |
| .show_fdinfo = bpf_prog_show_fdinfo, |
| #endif |
| .release = bpf_prog_release, |
| .read = bpf_dummy_read, |
| .write = bpf_dummy_write, |
| }; |
| |
| int bpf_prog_new_fd(struct bpf_prog *prog) |
| { |
| int ret; |
| |
| ret = security_bpf_prog(prog); |
| if (ret < 0) |
| return ret; |
| |
| return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, |
| O_RDWR | O_CLOEXEC); |
| } |
| |
| void bpf_prog_add(struct bpf_prog *prog, int i) |
| { |
| atomic64_add(i, &prog->aux->refcnt); |
| } |
| EXPORT_SYMBOL_GPL(bpf_prog_add); |
| |
| void bpf_prog_sub(struct bpf_prog *prog, int i) |
| { |
| /* Only to be used for undoing previous bpf_prog_add() in some |
| * error path. We still know that another entity in our call |
| * path holds a reference to the program, thus atomic_sub() can |
| * be safely used in such cases! |
| */ |
| WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0); |
| } |
| EXPORT_SYMBOL_GPL(bpf_prog_sub); |
| |
| void bpf_prog_inc(struct bpf_prog *prog) |
| { |
| atomic64_inc(&prog->aux->refcnt); |
| } |
| EXPORT_SYMBOL_GPL(bpf_prog_inc); |
| |
| /* prog_idr_lock should have been held */ |
| struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) |
| { |
| int refold; |
| |
| refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0); |
| |
| if (!refold) |
| return ERR_PTR(-ENOENT); |
| |
| return prog; |
| } |
| EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero); |
| |
| bool bpf_prog_get_ok(struct bpf_prog *prog, |
| enum bpf_prog_type *attach_type, bool attach_drv) |
| { |
| /* not an attachment, just a refcount inc, always allow */ |
| if (!attach_type) |
| return true; |
| |
| if (prog->type != *attach_type) |
| return false; |
| if (bpf_prog_is_offloaded(prog->aux) && !attach_drv) |
| return false; |
| |
| return true; |
| } |
| |
| static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type, |
| bool attach_drv) |
| { |
| CLASS(fd, f)(ufd); |
| struct bpf_prog *prog; |
| |
| if (fd_empty(f)) |
| return ERR_PTR(-EBADF); |
| if (fd_file(f)->f_op != &bpf_prog_fops) |
| return ERR_PTR(-EINVAL); |
| |
| prog = fd_file(f)->private_data; |
| if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) |
| return ERR_PTR(-EINVAL); |
| |
| bpf_prog_inc(prog); |
| return prog; |
| } |
| |
| struct bpf_prog *bpf_prog_get(u32 ufd) |
| { |
| return __bpf_prog_get(ufd, NULL, false); |
| } |
| |
| struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type, |
| bool attach_drv) |
| { |
| return __bpf_prog_get(ufd, &type, attach_drv); |
| } |
| EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev); |
| |
| /* Initially all BPF programs could be loaded w/o specifying |
| * expected_attach_type. Later for some of them specifying expected_attach_type |
| * at load time became required so that program could be validated properly. |
| * Programs of types that are allowed to be loaded both w/ and w/o (for |
| * backward compatibility) expected_attach_type, should have the default attach |
| * type assigned to expected_attach_type for the latter case, so that it can be |
| * validated later at attach time. |
| * |
| * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if |
| * prog type requires it but has some attach types that have to be backward |
| * compatible. |
| */ |
| static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr) |
| { |
| switch (attr->prog_type) { |
| case BPF_PROG_TYPE_CGROUP_SOCK: |
| /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't |
| * exist so checking for non-zero is the way to go here. |
| */ |
| if (!attr->expected_attach_type) |
| attr->expected_attach_type = |
| BPF_CGROUP_INET_SOCK_CREATE; |
| break; |
| case BPF_PROG_TYPE_SK_REUSEPORT: |
| if (!attr->expected_attach_type) |
| attr->expected_attach_type = |
| BPF_SK_REUSEPORT_SELECT; |
| break; |
| } |
| } |
| |
| static int |
| bpf_prog_load_check_attach(enum bpf_prog_type prog_type, |
| enum bpf_attach_type expected_attach_type, |
| struct btf *attach_btf, u32 btf_id, |
| struct bpf_prog *dst_prog) |
| { |
| if (btf_id) { |
| if (btf_id > BTF_MAX_TYPE) |
| return -EINVAL; |
| |
| if (!attach_btf && !dst_prog) |
| return -EINVAL; |
| |
| switch (prog_type) { |
| case BPF_PROG_TYPE_TRACING: |
| case BPF_PROG_TYPE_LSM: |
| case BPF_PROG_TYPE_STRUCT_OPS: |
| case BPF_PROG_TYPE_EXT: |
| break; |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| if (attach_btf && (!btf_id || dst_prog)) |
| return -EINVAL; |
| |
| if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING && |
| prog_type != BPF_PROG_TYPE_EXT) |
| return -EINVAL; |
| |
| switch (prog_type) { |
| case BPF_PROG_TYPE_CGROUP_SOCK: |
| switch (expected_attach_type) { |
| case BPF_CGROUP_INET_SOCK_CREATE: |
| case BPF_CGROUP_INET_SOCK_RELEASE: |
| case BPF_CGROUP_INET4_POST_BIND: |
| case BPF_CGROUP_INET6_POST_BIND: |
| return 0; |
| default: |
| return -EINVAL; |
| } |
| case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: |
| switch (expected_attach_type) { |
| case BPF_CGROUP_INET4_BIND: |
| case BPF_CGROUP_INET6_BIND: |
| case BPF_CGROUP_INET4_CONNECT: |
| case BPF_CGROUP_INET6_CONNECT: |
| case BPF_CGROUP_UNIX_CONNECT: |
| case BPF_CGROUP_INET4_GETPEERNAME: |
| case BPF_CGROUP_INET6_GETPEERNAME: |
| case BPF_CGROUP_UNIX_GETPEERNAME: |
| case BPF_CGROUP_INET4_GETSOCKNAME: |
| case BPF_CGROUP_INET6_GETSOCKNAME: |
| case BPF_CGROUP_UNIX_GETSOCKNAME: |
| case BPF_CGROUP_UDP4_SENDMSG: |
| case BPF_CGROUP_UDP6_SENDMSG: |
| case BPF_CGROUP_UNIX_SENDMSG: |
| case BPF_CGROUP_UDP4_RECVMSG: |
| case BPF_CGROUP_UDP6_RECVMSG: |
| case BPF_CGROUP_UNIX_RECVMSG: |
| return 0; |
| default: |
| return -EINVAL; |
| } |
| case BPF_PROG_TYPE_CGROUP_SKB: |
| switch (expected_attach_type) { |
| case BPF_CGROUP_INET_INGRESS: |
| case BPF_CGROUP_INET_EGRESS: |
| return 0; |
| default: |
| return -EINVAL; |
| } |
| case BPF_PROG_TYPE_CGROUP_SOCKOPT: |
| switch (expected_attach_type) { |
| case BPF_CGROUP_SETSOCKOPT: |
| case BPF_CGROUP_GETSOCKOPT: |
| return 0; |
| default: |
| return -EINVAL; |
| } |
| case BPF_PROG_TYPE_SK_LOOKUP: |
| if (expected_attach_type == BPF_SK_LOOKUP) |
| return 0; |
| return -EINVAL; |
| case BPF_PROG_TYPE_SK_REUSEPORT: |
| switch (expected_attach_type) { |
| case BPF_SK_REUSEPORT_SELECT: |
| case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE: |
| return 0; |
| default: |
| return -EINVAL; |
| } |
| case BPF_PROG_TYPE_NETFILTER: |
| if (expected_attach_type == BPF_NETFILTER) |
| return 0; |
| return -EINVAL; |
| case BPF_PROG_TYPE_SYSCALL: |
| case BPF_PROG_TYPE_EXT: |
| if (expected_attach_type) |
| return -EINVAL; |
| fallthrough; |
| default: |
| return 0; |
| } |
| } |
| |
| static bool is_net_admin_prog_type(enum bpf_prog_type prog_type) |
| { |
| switch (prog_type) { |
| case BPF_PROG_TYPE_SCHED_CLS: |
| case BPF_PROG_TYPE_SCHED_ACT: |
| case BPF_PROG_TYPE_XDP: |
| case BPF_PROG_TYPE_LWT_IN: |
| case BPF_PROG_TYPE_LWT_OUT: |
| case BPF_PROG_TYPE_LWT_XMIT: |
| case BPF_PROG_TYPE_LWT_SEG6LOCAL: |
| case BPF_PROG_TYPE_SK_SKB: |
| case BPF_PROG_TYPE_SK_MSG: |
| case BPF_PROG_TYPE_FLOW_DISSECTOR: |
| case BPF_PROG_TYPE_CGROUP_DEVICE: |
| case BPF_PROG_TYPE_CGROUP_SOCK: |
| case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: |
| case BPF_PROG_TYPE_CGROUP_SOCKOPT: |
| case BPF_PROG_TYPE_CGROUP_SYSCTL: |
| case BPF_PROG_TYPE_SOCK_OPS: |
| case BPF_PROG_TYPE_EXT: /* extends any prog */ |
| case BPF_PROG_TYPE_NETFILTER: |
| return true; |
| case BPF_PROG_TYPE_CGROUP_SKB: |
| /* always unpriv */ |
| case BPF_PROG_TYPE_SK_REUSEPORT: |
| /* equivalent to SOCKET_FILTER. need CAP_BPF only */ |
| default: |
| return false; |
| } |
| } |
| |
| static bool is_perfmon_prog_type(enum bpf_prog_type prog_type) |
| { |
| switch (prog_type) { |
| case BPF_PROG_TYPE_KPROBE: |
| case BPF_PROG_TYPE_TRACEPOINT: |
| case BPF_PROG_TYPE_PERF_EVENT: |
| case BPF_PROG_TYPE_RAW_TRACEPOINT: |
| case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: |
| case BPF_PROG_TYPE_TRACING: |
| case BPF_PROG_TYPE_LSM: |
| case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */ |
| case BPF_PROG_TYPE_EXT: /* extends any prog */ |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| /* last field in 'union bpf_attr' used by this command */ |
| #define BPF_PROG_LOAD_LAST_FIELD prog_token_fd |
| |
| static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) |
| { |
| enum bpf_prog_type type = attr->prog_type; |
| struct bpf_prog *prog, *dst_prog = NULL; |
| struct btf *attach_btf = NULL; |
| struct bpf_token *token = NULL; |
| bool bpf_cap; |
| int err; |
| char license[128]; |
| |
| if (CHECK_ATTR(BPF_PROG_LOAD)) |
| return -EINVAL; |
| |
| if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | |
| BPF_F_ANY_ALIGNMENT | |
| BPF_F_TEST_STATE_FREQ | |
| BPF_F_SLEEPABLE | |
| BPF_F_TEST_RND_HI32 | |
| BPF_F_XDP_HAS_FRAGS | |
| BPF_F_XDP_DEV_BOUND_ONLY | |
| BPF_F_TEST_REG_INVARIANTS | |
| BPF_F_TOKEN_FD)) |
| return -EINVAL; |
| |
| bpf_prog_load_fixup_attach_type(attr); |
| |
| if (attr->prog_flags & BPF_F_TOKEN_FD) { |
| token = bpf_token_get_from_fd(attr->prog_token_fd); |
| if (IS_ERR(token)) |
| return PTR_ERR(token); |
| /* if current token doesn't grant prog loading permissions, |
| * then we can't use this token, so ignore it and rely on |
| * system-wide capabilities checks |
| */ |
| if (!bpf_token_allow_cmd(token, BPF_PROG_LOAD) || |
| !bpf_token_allow_prog_type(token, attr->prog_type, |
| attr->expected_attach_type)) { |
| bpf_token_put(token); |
| token = NULL; |
| } |
| } |
| |
| bpf_cap = bpf_token_capable(token, CAP_BPF); |
| err = -EPERM; |
| |
| if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && |
| (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && |
| !bpf_cap) |
| goto put_token; |
| |
| /* Intent here is for unprivileged_bpf_disabled to block BPF program |
| * creation for unprivileged users; other actions depend |
| * on fd availability and access to bpffs, so are dependent on |
| * object creation success. Even with unprivileged BPF disabled, |
| * capability checks are still carried out for these |
| * and other operations. |
| */ |
| if (sysctl_unprivileged_bpf_disabled && !bpf_cap) |
| goto put_token; |
| |
| if (attr->insn_cnt == 0 || |
| attr->insn_cnt > (bpf_cap ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) { |
| err = -E2BIG; |
| goto put_token; |
| } |
| if (type != BPF_PROG_TYPE_SOCKET_FILTER && |
| type != BPF_PROG_TYPE_CGROUP_SKB && |
| !bpf_cap) |
| goto put_token; |
| |
| if (is_net_admin_prog_type(type) && !bpf_token_capable(token, CAP_NET_ADMIN)) |
| goto put_token; |
| if (is_perfmon_prog_type(type) && !bpf_token_capable(token, CAP_PERFMON)) |
| goto put_token; |
| |
| /* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog |
| * or btf, we need to check which one it is |
| */ |
| if (attr->attach_prog_fd) { |
| dst_prog = bpf_prog_get(attr->attach_prog_fd); |
| if (IS_ERR(dst_prog)) { |
| dst_prog = NULL; |
| attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd); |
| if (IS_ERR(attach_btf)) { |
| err = -EINVAL; |
| goto put_token; |
| } |
| if (!btf_is_kernel(attach_btf)) { |
| /* attaching through specifying bpf_prog's BTF |
| * objects directly might be supported eventually |
| */ |
| btf_put(attach_btf); |
| err = -ENOTSUPP; |
| goto put_token; |
| } |
| } |
| } else if (attr->attach_btf_id) { |
| /* fall back to vmlinux BTF, if BTF type ID is specified */ |
| attach_btf = bpf_get_btf_vmlinux(); |
| if (IS_ERR(attach_btf)) { |
| err = PTR_ERR(attach_btf); |
| goto put_token; |
| } |
| if (!attach_btf) { |
| err = -EINVAL; |
| goto put_token; |
| } |
| btf_get(attach_btf); |
| } |
| |
| if (bpf_prog_load_check_attach(type, attr->expected_attach_type, |
| attach_btf, attr->attach_btf_id, |
| dst_prog)) { |
| if (dst_prog) |
| bpf_prog_put(dst_prog); |
| if (attach_btf) |
| btf_put(attach_btf); |
| err = -EINVAL; |
| goto put_token; |
| } |
| |
| /* plain bpf_prog allocation */ |
| prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); |
| if (!prog) { |
| if (dst_prog) |
| bpf_prog_put(dst_prog); |
| if (attach_btf) |
| btf_put(attach_btf); |
| err = -EINVAL; |
| goto put_token; |
| } |
| |
| prog->expected_attach_type = attr->expected_attach_type; |
| prog->sleepable = !!(attr->prog_flags & BPF_F_SLEEPABLE); |
| prog->aux->attach_btf = attach_btf; |
| prog->aux->attach_btf_id = attr->attach_btf_id; |
| prog->aux->dst_prog = dst_prog; |
| prog->aux->dev_bound = !!attr->prog_ifindex; |
| prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS; |
| |
| /* move token into prog->aux, reuse taken refcnt */ |
| prog->aux->token = token; |
| token = NULL; |
| |
| prog->aux->user = get_current_user(); |
| prog->len = attr->insn_cnt; |
| |
| err = -EFAULT; |
| if (copy_from_bpfptr(prog->insns, |
| make_bpfptr(attr->insns, uattr.is_kernel), |
| bpf_prog_insn_size(prog)) != 0) |
| goto free_prog; |
| /* copy eBPF program license from user space */ |
| if (strncpy_from_bpfptr(license, |
| make_bpfptr(attr->license, uattr.is_kernel), |
| sizeof(license) - 1) < 0) |
| goto free_prog; |
| license[sizeof(license) - 1] = 0; |
| |
| /* eBPF programs must be GPL compatible to use GPL-ed functions */ |
| prog->gpl_compatible = license_is_gpl_compatible(license) ? 1 : 0; |
| |
| prog->orig_prog = NULL; |
| prog->jited = 0; |
| |
| atomic64_set(&prog->aux->refcnt, 1); |
| |
| if (bpf_prog_is_dev_bound(prog->aux)) { |
| err = bpf_prog_dev_bound_init(prog, attr); |
| if (err) |
| goto free_prog; |
| } |
| |
| if (type == BPF_PROG_TYPE_EXT && dst_prog && |
| bpf_prog_is_dev_bound(dst_prog->aux)) { |
| err = bpf_prog_dev_bound_inherit(prog, dst_prog); |
| if (err) |
| goto free_prog; |
| } |
| |
| /* |
| * Bookkeeping for managing the program attachment chain. |
| * |
| * It might be tempting to set attach_tracing_prog flag at the attachment |
| * time, but this will not prevent from loading bunch of tracing prog |
| * first, then attach them one to another. |
| * |
| * The flag attach_tracing_prog is set for the whole program lifecycle, and |
| * doesn't have to be cleared in bpf_tracing_link_release, since tracing |
| * programs cannot change attachment target. |
| */ |
| if (type == BPF_PROG_TYPE_TRACING && dst_prog && |
| dst_prog->type == BPF_PROG_TYPE_TRACING) { |
| prog->aux->attach_tracing_prog = true; |
| } |
| |
| /* find program type: socket_filter vs tracing_filter */ |
| err = find_prog_type(type, prog); |
| if (err < 0) |
| goto free_prog; |
| |
| prog->aux->load_time = ktime_get_boottime_ns(); |
| err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name, |
| sizeof(attr->prog_name)); |
| if (err < 0) |
| goto free_prog; |
| |
| err = security_bpf_prog_load(prog, attr, token); |
| if (err) |
| goto free_prog_sec; |
| |
| /* run eBPF verifier */ |
| err = bpf_check(&prog, attr, uattr, uattr_size); |
| if (err < 0) |
| goto free_used_maps; |
| |
| prog = bpf_prog_select_runtime(prog, &err); |
| if (err < 0) |
| goto free_used_maps; |
| |
| err = bpf_prog_alloc_id(prog); |
| if (err) |
| goto free_used_maps; |
| |
| /* Upon success of bpf_prog_alloc_id(), the BPF prog is |
| * effectively publicly exposed. However, retrieving via |
| * bpf_prog_get_fd_by_id() will take another reference, |
| * therefore it cannot be gone underneath us. |
| * |
| * Only for the time /after/ successful bpf_prog_new_fd() |
| * and before returning to userspace, we might just hold |
| * one reference and any parallel close on that fd could |
| * rip everything out. Hence, below notifications must |
| * happen before bpf_prog_new_fd(). |
| * |
| * Also, any failure handling from this point onwards must |
| * be using bpf_prog_put() given the program is exposed. |
| */ |
| bpf_prog_kallsyms_add(prog); |
| perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); |
| bpf_audit_prog(prog, BPF_AUDIT_LOAD); |
| |
| err = bpf_prog_new_fd(prog); |
| if (err < 0) |
| bpf_prog_put(prog); |
| return err; |
| |
| free_used_maps: |
| /* In case we have subprogs, we need to wait for a grace |
| * period before we can tear down JIT memory since symbols |
| * are already exposed under kallsyms. |
| */ |
| __bpf_prog_put_noref(prog, prog->aux->real_func_cnt); |
| return err; |
| |
| free_prog_sec: |
| security_bpf_prog_free(prog); |
| free_prog: |
| free_uid(prog->aux->user); |
| if (prog->aux->attach_btf) |
| btf_put(prog->aux->attach_btf); |
| bpf_prog_free(prog); |
| put_token: |
| bpf_token_put(token); |
| return err; |
| } |
| |
| #define BPF_OBJ_LAST_FIELD path_fd |
| |
| static int bpf_obj_pin(const union bpf_attr *attr) |
| { |
| int path_fd; |
| |
| if (CHECK_ATTR(BPF_OBJ) || attr->file_flags & ~BPF_F_PATH_FD) |
| return -EINVAL; |
| |
| /* path_fd has to be accompanied by BPF_F_PATH_FD flag */ |
| if (!(attr->file_flags & BPF_F_PATH_FD) && attr->path_fd) |
| return -EINVAL; |
| |
| path_fd = attr->file_flags & BPF_F_PATH_FD ? attr->path_fd : AT_FDCWD; |
| return bpf_obj_pin_user(attr->bpf_fd, path_fd, |
| u64_to_user_ptr(attr->pathname)); |
| } |
| |
| static int bpf_obj_get(const union bpf_attr *attr) |
| { |
| int path_fd; |
| |
| if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 || |
| attr->file_flags & ~(BPF_OBJ_FLAG_MASK | BPF_F_PATH_FD)) |
| return -EINVAL; |
| |
| /* path_fd has to be accompanied by BPF_F_PATH_FD flag */ |
| if (!(attr->file_flags & BPF_F_PATH_FD) && attr->path_fd) |
| return -EINVAL; |
| |
| path_fd = attr->file_flags & BPF_F_PATH_FD ? attr->path_fd : AT_FDCWD; |
| return bpf_obj_get_user(path_fd, u64_to_user_ptr(attr->pathname), |
| attr->file_flags); |
| } |
| |
| void bpf_link_init(struct bpf_link *link, enum bpf_link_type type, |
| const struct bpf_link_ops *ops, struct bpf_prog *prog) |
| { |
| WARN_ON(ops->dealloc && ops->dealloc_deferred); |
| atomic64_set(&link->refcnt, 1); |
| link->type = type; |
| link->id = 0; |
| link->ops = ops; |
| link->prog = prog; |
| } |
| |
| static void bpf_link_free_id(int id) |
| { |
| if (!id) |
| return; |
| |
| spin_lock_bh(&link_idr_lock); |
| idr_remove(&link_idr, id); |
| spin_unlock_bh(&link_idr_lock); |
| } |
| |
| /* Clean up bpf_link and corresponding anon_inode file and FD. After |
| * anon_inode is created, bpf_link can't be just kfree()'d due to deferred |
| * anon_inode's release() call. This helper marks bpf_link as |
| * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt |
| * is not decremented, it's the responsibility of a calling code that failed |
| * to complete bpf_link initialization. |
| * This helper eventually calls link's dealloc callback, but does not call |
| * link's release callback. |
| */ |
| void bpf_link_cleanup(struct bpf_link_primer *primer) |
| { |
| primer->link->prog = NULL; |
| bpf_link_free_id(primer->id); |
| fput(primer->file); |
| put_unused_fd(primer->fd); |
| } |
| |
| void bpf_link_inc(struct bpf_link *link) |
| { |
| atomic64_inc(&link->refcnt); |
| } |
| |
| static void bpf_link_defer_dealloc_rcu_gp(struct rcu_head *rcu) |
| { |
| struct bpf_link *link = container_of(rcu, struct bpf_link, rcu); |
| |
| /* free bpf_link and its containing memory */ |
| link->ops->dealloc_deferred(link); |
| } |
| |
| static void bpf_link_defer_dealloc_mult_rcu_gp(struct rcu_head *rcu) |
| { |
| if (rcu_trace_implies_rcu_gp()) |
| bpf_link_defer_dealloc_rcu_gp(rcu); |
| else |
| call_rcu(rcu, bpf_link_defer_dealloc_rcu_gp); |
| } |
| |
| /* bpf_link_free is guaranteed to be called from process context */ |
| static void bpf_link_free(struct bpf_link *link) |
| { |
| const struct bpf_link_ops *ops = link->ops; |
| bool sleepable = false; |
| |
| bpf_link_free_id(link->id); |
| if (link->prog) { |
| sleepable = link->prog->sleepable; |
| /* detach BPF program, clean up used resources */ |
| ops->release(link); |
| bpf_prog_put(link->prog); |
| } |
| if (ops->dealloc_deferred) { |
| /* schedule BPF link deallocation; if underlying BPF program |
| * is sleepable, we need to first wait for RCU tasks trace |
| * sync, then go through "classic" RCU grace period |
| */ |
| if (sleepable) |
| call_rcu_tasks_trace(&link->rcu, bpf_link_defer_dealloc_mult_rcu_gp); |
| else |
| call_rcu(&link->rcu, bpf_link_defer_dealloc_rcu_gp); |
| } else if (ops->dealloc) |
| ops->dealloc(link); |
| } |
| |
| static void bpf_link_put_deferred(struct work_struct *work) |
| { |
| struct bpf_link *link = container_of(work, struct bpf_link, work); |
| |
| bpf_link_free(link); |
| } |
| |
| /* bpf_link_put might be called from atomic context. It needs to be called |
| * from sleepable context in order to acquire sleeping locks during the process. |
| */ |
| void bpf_link_put(struct bpf_link *link) |
| { |
| if (!atomic64_dec_and_test(&link->refcnt)) |
| return; |
| |
| INIT_WORK(&link->work, bpf_link_put_deferred); |
| schedule_work(&link->work); |
| } |
| EXPORT_SYMBOL(bpf_link_put); |
| |
| static void bpf_link_put_direct(struct bpf_link *link) |
| { |
| if (!atomic64_dec_and_test(&link->refcnt)) |
| return; |
| bpf_link_free(link); |
| } |
| |
| static int bpf_link_release(struct inode *inode, struct file *filp) |
| { |
| struct bpf_link *link = filp->private_data; |
| |
| bpf_link_put_direct(link); |
| return 0; |
| } |
| |
| #ifdef CONFIG_PROC_FS |
| #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) |
| #define BPF_MAP_TYPE(_id, _ops) |
| #define BPF_LINK_TYPE(_id, _name) [_id] = #_name, |
| static const char *bpf_link_type_strs[] = { |
| [BPF_LINK_TYPE_UNSPEC] = "<invalid>", |
| #include <linux/bpf_types.h> |
| }; |
| #undef BPF_PROG_TYPE |
| #undef BPF_MAP_TYPE |
| #undef BPF_LINK_TYPE |
| |
| static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp) |
| { |
| const struct bpf_link *link = filp->private_data; |
| const struct bpf_prog *prog = link->prog; |
| char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; |
| |
| seq_printf(m, |
| "link_type:\t%s\n" |
| "link_id:\t%u\n", |
| bpf_link_type_strs[link->type], |
| link->id); |
| if (prog) { |
| bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); |
| seq_printf(m, |
| "prog_tag:\t%s\n" |
| "prog_id:\t%u\n", |
| prog_tag, |
| prog->aux->id); |
| } |
| if (link->ops->show_fdinfo) |
| link->ops->show_fdinfo(link, m); |
| } |
| #endif |
| |
| static __poll_t bpf_link_poll(struct file *file, struct poll_table_struct *pts) |
| { |
| struct bpf_link *link = file->private_data; |
| |
| return link->ops->poll(file, pts); |
| } |
| |
| static const struct file_operations bpf_link_fops = { |
| #ifdef CONFIG_PROC_FS |
| .show_fdinfo = bpf_link_show_fdinfo, |
| #endif |
| .release = bpf_link_release, |
| .read = bpf_dummy_read, |
| .write = bpf_dummy_write, |
| }; |
| |
| static const struct file_operations bpf_link_fops_poll = { |
| #ifdef CONFIG_PROC_FS |
| .show_fdinfo = bpf_link_show_fdinfo, |
| #endif |
| .release = bpf_link_release, |
| .read = bpf_dummy_read, |
| .write = bpf_dummy_write, |
| .poll = bpf_link_poll, |
| }; |
| |
| static int bpf_link_alloc_id(struct bpf_link *link) |
| { |
| int id; |
| |
| idr_preload(GFP_KERNEL); |
| spin_lock_bh(&link_idr_lock); |
| id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC); |
| spin_unlock_bh(&link_idr_lock); |
| idr_preload_end(); |
| |
| return id; |
| } |
| |
| /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file, |
| * reserving unused FD and allocating ID from link_idr. This is to be paired |
| * with bpf_link_settle() to install FD and ID and expose bpf_link to |
| * user-space, if bpf_link is successfully attached. If not, bpf_link and |
| * pre-allocated resources are to be freed with bpf_cleanup() call. All the |
| * transient state is passed around in struct bpf_link_primer. |
| * This is preferred way to create and initialize bpf_link, especially when |
| * there are complicated and expensive operations in between creating bpf_link |
| * itself and attaching it to BPF hook. By using bpf_link_prime() and |
| * bpf_link_settle() kernel code using bpf_link doesn't have to perform |
| * expensive (and potentially failing) roll back operations in a rare case |
| * that file, FD, or ID can't be allocated. |
| */ |
| int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer) |
| { |
| struct file *file; |
| int fd, id; |
| |
| fd = get_unused_fd_flags(O_CLOEXEC); |
| if (fd < 0) |
| return fd; |
| |
| |
| id = bpf_link_alloc_id(link); |
| if (id < 0) { |
| put_unused_fd(fd); |
| return id; |
| } |
| |
| file = anon_inode_getfile("bpf_link", |
| link->ops->poll ? &bpf_link_fops_poll : &bpf_link_fops, |
| link, O_CLOEXEC); |
| if (IS_ERR(file)) { |
| bpf_link_free_id(id); |
| put_unused_fd(fd); |
| return PTR_ERR(file); |
| } |
| |
| primer->link = link; |
| primer->file = file; |
| primer->fd = fd; |
| primer->id = id; |
| return 0; |
| } |
| |
| int bpf_link_settle(struct bpf_link_primer *primer) |
| { |
| /* make bpf_link fetchable by ID */ |
| spin_lock_bh(&link_idr_lock); |
| primer->link->id = primer->id; |
| spin_unlock_bh(&link_idr_lock); |
| /* make bpf_link fetchable by FD */ |
| fd_install(primer->fd, primer->file); |
| /* pass through installed FD */ |
| return primer->fd; |
| } |
| |
| int bpf_link_new_fd(struct bpf_link *link) |
| { |
| return anon_inode_getfd("bpf-link", |
| link->ops->poll ? &bpf_link_fops_poll : &bpf_link_fops, |
| link, O_CLOEXEC); |
| } |
| |
| struct bpf_link *bpf_link_get_from_fd(u32 ufd) |
| { |
| CLASS(fd, f)(ufd); |
| struct bpf_link *link; |
| |
| if (fd_empty(f)) |
| return ERR_PTR(-EBADF); |
| if (fd_file(f)->f_op != &bpf_link_fops && fd_file(f)->f_op != &bpf_link_fops_poll) |
| return ERR_PTR(-EINVAL); |
| |
| link = fd_file(f)->private_data; |
| bpf_link_inc(link); |
| return link; |
| } |
| EXPORT_SYMBOL(bpf_link_get_from_fd); |
| |
| static void bpf_tracing_link_release(struct bpf_link *link) |
| { |
| struct bpf_tracing_link *tr_link = |
| container_of(link, struct bpf_tracing_link, link.link); |
| |
| WARN_ON_ONCE(bpf_trampoline_unlink_prog(&tr_link->link, |
| tr_link->trampoline)); |
| |
| bpf_trampoline_put(tr_link->trampoline); |
| |
| /* tgt_prog is NULL if target is a kernel function */ |
| if (tr_link->tgt_prog) |
| bpf_prog_put(tr_link->tgt_prog); |
| } |
| |
| static void bpf_tracing_link_dealloc(struct bpf_link *link) |
| { |
| struct bpf_tracing_link *tr_link = |
| container_of(link, struct bpf_tracing_link, link.link); |
| |
| kfree(tr_link); |
| } |
| |
| static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link, |
| struct seq_file *seq) |
| { |
| struct bpf_tracing_link *tr_link = |
| container_of(link, struct bpf_tracing_link, link.link); |
| u32 target_btf_id, target_obj_id; |
| |
| bpf_trampoline_unpack_key(tr_link->trampoline->key, |
| &target_obj_id, &target_btf_id); |
| seq_printf(seq, |
| "attach_type:\t%d\n" |
| "target_obj_id:\t%u\n" |
| "target_btf_id:\t%u\n", |
| tr_link->attach_type, |
| target_obj_id, |
| target_btf_id); |
| } |
| |
| static int bpf_tracing_link_fill_link_info(const struct bpf_link *link, |
| struct bpf_link_info *info) |
| { |
| struct bpf_tracing_link *tr_link = |
| container_of(link, struct bpf_tracing_link, link.link); |
| |
| info->tracing.attach_type = tr_link->attach_type; |
| bpf_trampoline_unpack_key(tr_link->trampoline->key, |
| &info->tracing.target_obj_id, |
| &info->tracing.target_btf_id); |
| |
| return 0; |
| } |
| |
| static const struct bpf_link_ops bpf_tracing_link_lops = { |
| .release = bpf_tracing_link_release, |
| .dealloc = bpf_tracing_link_dealloc, |
| .show_fdinfo = bpf_tracing_link_show_fdinfo, |
| .fill_link_info = bpf_tracing_link_fill_link_info, |
| }; |
| |
| static int bpf_tracing_prog_attach(struct bpf_prog *prog, |
| int tgt_prog_fd, |
| u32 btf_id, |
| u64 bpf_cookie) |
| { |
| struct bpf_link_primer link_primer; |
| struct bpf_prog *tgt_prog = NULL; |
| struct bpf_trampoline *tr = NULL; |
| struct bpf_tracing_link *link; |
| u64 key = 0; |
| int err; |
| |
| switch (prog->type) { |
| case BPF_PROG_TYPE_TRACING: |
| if (prog->expected_attach_type != BPF_TRACE_FENTRY && |
| prog->expected_attach_type != BPF_TRACE_FEXIT && |
| prog->expected_attach_type != BPF_MODIFY_RETURN) { |
| err = -EINVAL; |
| goto out_put_prog; |
| } |
| break; |
| case BPF_PROG_TYPE_EXT: |
| if (prog->expected_attach_type != 0) { |
| err = -EINVAL; |
| goto out_put_prog; |
| } |
| break; |
| case BPF_PROG_TYPE_LSM: |
| if (prog->expected_attach_type != BPF_LSM_MAC) { |
| err = -EINVAL; |
| goto out_put_prog; |
| } |
| break; |
| default: |
| err = -EINVAL; |
| goto out_put_prog; |
| } |
| |
| if (!!tgt_prog_fd != !!btf_id) { |
| err = -EINVAL; |
| goto out_put_prog; |
| } |
| |
| if (tgt_prog_fd) { |
| /* |
| * For now we only allow new targets for BPF_PROG_TYPE_EXT. If this |
| * part would be changed to implement the same for |
| * BPF_PROG_TYPE_TRACING, do not forget to update the way how |
| * attach_tracing_prog flag is set. |
| */ |
| if (prog->type != BPF_PROG_TYPE_EXT) { |
| err = -EINVAL; |
| goto out_put_prog; |
| } |
| |
| tgt_prog = bpf_prog_get(tgt_prog_fd); |
| if (IS_ERR(tgt_prog)) { |
| err = PTR_ERR(tgt_prog); |
| tgt_prog = NULL; |
| goto out_put_prog; |
| } |
| |
| key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id); |
| } |
| |
| link = kzalloc(sizeof(*link), GFP_USER); |
| if (!link) { |
| err = -ENOMEM; |
| goto out_put_prog; |
| } |
| bpf_link_init(&link->link.link, BPF_LINK_TYPE_TRACING, |
| &bpf_tracing_link_lops, prog); |
| link->attach_type = prog->expected_attach_type; |
| link->link.cookie = bpf_cookie; |
| |
| mutex_lock(&prog->aux->dst_mutex); |
| |
| /* There are a few possible cases here: |
| * |
| * - if prog->aux->dst_trampoline is set, the program was just loaded |
| * and not yet attached to anything, so we can use the values stored |
| * in prog->aux |
| * |
| * - if prog->aux->dst_trampoline is NULL, the program has already been |
| * attached to a target and its initial target was cleared (below) |
| * |
| * - if tgt_prog != NULL, the caller specified tgt_prog_fd + |
| * target_btf_id using the link_create API. |
| * |
| * - if tgt_prog == NULL when this function was called using the old |
| * raw_tracepoint_open API, and we need a target from prog->aux |
| * |
| * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program |
| * was detached and is going for re-attachment. |
| * |
| * - if prog->aux->dst_trampoline is NULL and tgt_prog and prog->aux->attach_btf |
| * are NULL, then program was already attached and user did not provide |
| * tgt_prog_fd so we have no way to find out or create trampoline |
| */ |
| if (!prog->aux->dst_trampoline && !tgt_prog) { |
| /* |
| * Allow re-attach for TRACING and LSM programs. If it's |
| * currently linked, bpf_trampoline_link_prog will fail. |
| * EXT programs need to specify tgt_prog_fd, so they |
| * re-attach in separate code path. |
| */ |
| if (prog->type != BPF_PROG_TYPE_TRACING && |
| prog->type != BPF_PROG_TYPE_LSM) { |
| err = -EINVAL; |
| goto out_unlock; |
| } |
| /* We can allow re-attach only if we have valid attach_btf. */ |
| if (!prog->aux->attach_btf) { |
| err = -EINVAL; |
| goto out_unlock; |
| } |
| btf_id = prog->aux->attach_btf_id; |
| key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id); |
| } |
| |
| if (!prog->aux->dst_trampoline || |
| (key && key != prog->aux->dst_trampoline->key)) { |
| /* If there is no saved target, or the specified target is |
| * different from the destination specified at load time, we |
| * need a new trampoline and a check for compatibility |
| */ |
| struct bpf_attach_target_info tgt_info = {}; |
| |
| err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id, |
| &tgt_info); |
| if (err) |
| goto out_unlock; |
| |
| if (tgt_info.tgt_mod) { |
| module_put(prog->aux->mod); |
| prog->aux->mod = tgt_info.tgt_mod; |
| } |
| |
| tr = bpf_trampoline_get(key, &tgt_info); |
| if (!tr) { |
| err = -ENOMEM; |
| goto out_unlock; |
| } |
| } else { |
| /* The caller didn't specify a target, or the target was the |
| * same as the destination supplied during program load. This |
| * means we can reuse the trampoline and reference from program |
| * load time, and there is no need to allocate a new one. This |
| * can only happen once for any program, as the saved values in |
| * prog->aux are cleared below. |
| */ |
| tr = prog->aux->dst_trampoline; |
| tgt_prog = prog->aux->dst_prog; |
| } |
| |
| err = bpf_link_prime(&link->link.link, &link_primer); |
| if (err) |
| goto out_unlock; |
| |
| err = bpf_trampoline_link_prog(&link->link, tr); |
| if (err) { |
| bpf_link_cleanup(&link_primer); |
| link = NULL; |
| goto out_unlock; |
| } |
| |
| link->tgt_prog = tgt_prog; |
| link->trampoline = tr; |
| |
| /* Always clear the trampoline and target prog from prog->aux to make |
| * sure the original attach destination is not kept alive after a |
| * program is (re-)attached to another target. |
| */ |
| if (prog->aux->dst_prog && |
| (tgt_prog_fd || tr != prog->aux->dst_trampoline)) |
| /* got extra prog ref from syscall, or attaching to different prog */ |
| bpf_prog_put(prog->aux->dst_prog); |
| if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline) |
| /* we allocated a new trampoline, so free the old one */ |
| bpf_trampoline_put(prog->aux->dst_trampoline); |
| |
| prog->aux->dst_prog = NULL; |
| prog->aux->dst_trampoline = NULL; |
| mutex_unlock(&prog->aux->dst_mutex); |
| |
| return bpf_link_settle(&link_primer); |
| out_unlock: |
| if (tr && tr != prog->aux->dst_trampoline) |
| bpf_trampoline_put(tr); |
| mutex_unlock(&prog->aux->dst_mutex); |
| kfree(link); |
| out_put_prog: |
| if (tgt_prog_fd && tgt_prog) |
| bpf_prog_put(tgt_prog); |
| return err; |
| } |
| |
| static void bpf_raw_tp_link_release(struct bpf_link *link) |
| { |
| struct bpf_raw_tp_link *raw_tp = |
| container_of(link, struct bpf_raw_tp_link, link); |
| |
| bpf_probe_unregister(raw_tp->btp, raw_tp); |
| bpf_put_raw_tracepoint(raw_tp->btp); |
| } |
| |
| static void bpf_raw_tp_link_dealloc(struct bpf_link *link) |
| { |
| struct bpf_raw_tp_link *raw_tp = |
| container_of(link, struct bpf_raw_tp_link, link); |
| |
| kfree(raw_tp); |
| } |
| |
| static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link, |
| struct seq_file *seq) |
| { |
| struct bpf_raw_tp_link *raw_tp_link = |
| container_of(link, struct bpf_raw_tp_link, link); |
| |
| seq_printf(seq, |
| "tp_name:\t%s\n", |
| raw_tp_link->btp->tp->name); |
| } |
| |
| static int bpf_copy_to_user(char __user *ubuf, const char *buf, u32 ulen, |
| u32 len) |
| { |
| if (ulen >= len + 1) { |
| if (copy_to_user(ubuf, buf, len + 1)) |
| return -EFAULT; |
| } else { |
| char zero = '\0'; |
| |
| if (copy_to_user(ubuf, buf, ulen - 1)) |
| return -EFAULT; |
| if (put_user(zero, ubuf + ulen - 1)) |
| return -EFAULT; |
| return -ENOSPC; |
| } |
| |
| return 0; |
| } |
| |
| static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link, |
| struct bpf_link_info *info) |
| { |
| struct bpf_raw_tp_link *raw_tp_link = |
| container_of(link, struct bpf_raw_tp_link, link); |
| char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name); |
| const char *tp_name = raw_tp_link->btp->tp->name; |
| u32 ulen = info->raw_tracepoint.tp_name_len; |
| size_t tp_len = strlen(tp_name); |
| |
| if (!ulen ^ !ubuf) |
| return -EINVAL; |
| |
| info->raw_tracepoint.tp_name_len = tp_len + 1; |
| |
| if (!ubuf) |
| return 0; |
| |
| return bpf_copy_to_user(ubuf, tp_name, ulen, tp_len); |
| } |
| |
| static const struct bpf_link_ops bpf_raw_tp_link_lops = { |
| .release = bpf_raw_tp_link_release, |
| .dealloc_deferred = bpf_raw_tp_link_dealloc, |
| .show_fdinfo = bpf_raw_tp_link_show_fdinfo, |
| .fill_link_info = bpf_raw_tp_link_fill_link_info, |
| }; |
| |
| #ifdef CONFIG_PERF_EVENTS |
| struct bpf_perf_link { |
| struct bpf_link link; |
| struct file *perf_file; |
| }; |
| |
| static void bpf_perf_link_release(struct bpf_link *link) |
| { |
| struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); |
| struct perf_event *event = perf_link->perf_file->private_data; |
| |
| perf_event_free_bpf_prog(event); |
| fput(perf_link->perf_file); |
| } |
| |
| static void bpf_perf_link_dealloc(struct bpf_link *link) |
| { |
| struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link); |
| |
| kfree(perf_link); |
| } |
| |
| static int bpf_perf_link_fill_common(const struct perf_event *event, |
| char __user *uname, u32 ulen, |
| u64 *probe_offset, u64 *probe_addr, |
| u32 *fd_type, unsigned long *missed) |
| { |
| const char *buf; |
| u32 prog_id; |
| size_t len; |
| int err; |
| |
| if (!ulen ^ !uname) |
| return -EINVAL; |
| |
| err = bpf_get_perf_event_info(event, &prog_id, fd_type, &buf, |
| probe_offset, probe_addr, missed); |
| if (err) |
| return err; |
| if (!uname) |
| return 0; |
| if (buf) { |
| len = strlen(buf); |
| err = bpf_copy_to_user(uname, buf, ulen, len); |
| if (err) |
| return err; |
| } else { |
| char zero = '\0'; |
| |
| if (put_user(zero, uname)) |
| return -EFAULT; |
| } |
| return 0; |
| } |
| |
| #ifdef CONFIG_KPROBE_EVENTS |
| static int bpf_perf_link_fill_kprobe(const struct perf_event *event, |
| struct bpf_link_info *info) |
| { |
| unsigned long missed; |
| char __user *uname; |
| u64 addr, offset; |
| u32 ulen, type; |
| int err; |
| |
| uname = u64_to_user_ptr(info->perf_event.kprobe.func_name); |
| ulen = info->perf_event.kprobe.name_len; |
| err = bpf_perf_link_fill_common(event, uname, ulen, &offset, &addr, |
| &type, &missed); |
| if (err) |
| return err; |
| if (type == BPF_FD_TYPE_KRETPROBE) |
| info->perf_event.type = BPF_PERF_EVENT_KRETPROBE; |
| else |
| info->perf_event.type = BPF_PERF_EVENT_KPROBE; |
| |
| info->perf_event.kprobe.offset = offset; |
| info->perf_event.kprobe.missed = missed; |
| if (!kallsyms_show_value(current_cred())) |
| addr = 0; |
| info->perf_event.kprobe.addr = addr; |
| info->perf_event.kprobe.cookie = event->bpf_cookie; |
| return 0; |
| } |
| #endif |
| |
| #ifdef CONFIG_UPROBE_EVENTS |
| static int bpf_perf_link_fill_uprobe(const struct perf_event *event, |
| struct bpf_link_info *info) |
| { |
| char __user *uname; |
| u64 addr, offset; |
| u32 ulen, type; |
| int err; |
| |
| uname = u64_to_user_ptr(info->perf_event.uprobe.file_name); |
| ulen = info->perf_event.uprobe.name_len; |
| err = bpf_perf_link_fill_common(event, uname, ulen, &offset, &addr, |
| &type, NULL); |
| if (err) |
| return err; |
| |
| if (type == BPF_FD_TYPE_URETPROBE) |
| info->perf_event.type = BPF_PERF_EVENT_URETPROBE; |
| else |
| info->perf_event.type = BPF_PERF_EVENT_UPROBE; |
| info->perf_event.uprobe.offset = offset; |
| info->perf_event.uprobe.cookie = event->bpf_cookie; |
| return 0; |
| } |
| #endif |
| |
| static int bpf_perf_link_fill_probe(const struct perf_event *event, |
| struct bpf_link_info *info) |
| { |
| #ifdef CONFIG_KPROBE_EVENTS |
| if (event->tp_event->flags & TRACE_EVENT_FL_KPROBE) |
| return bpf_perf_link_fill_kprobe(event, info); |
| #endif |
| #ifdef CONFIG_UPROBE_EVENTS |
| if (event->tp_event->flags & TRACE_EVENT_FL_UPROBE) |
| return bpf_perf_link_fill_uprobe(event, info); |
| #endif |
| return -EOPNOTSUPP; |
| } |
| |
| static int bpf_perf_link_fill_tracepoint(const struct perf_event *event, |
| struct bpf_link_info *info) |
| { |
| char __user *uname; |
| u32 ulen; |
| |
| uname = u64_to_user_ptr(info->perf_event.tracepoint.tp_name); |
| ulen = info->perf_event.tracepoint.name_len; |
| info->perf_event.type = BPF_PERF_EVENT_TRACEPOINT; |
| info->perf_event.tracepoint.cookie = event->bpf_cookie; |
| return bpf_perf_link_fill_common(event, uname, ulen, NULL, NULL, NULL, NULL); |
| } |
| |
| static int bpf_perf_link_fill_perf_event(const struct perf_event *event, |
| struct bpf_link_info *info) |
| { |
| info->perf_event.event.type = event->attr.type; |
| info->perf_event.event.config = event->attr.config; |
| info->perf_event.event.cookie = event->bpf_cookie; |
| info->perf_event.type = BPF_PERF_EVENT_EVENT; |
| return 0; |
| } |
| |
| static int bpf_perf_link_fill_link_info(const struct bpf_link *link, |
| struct bpf_link_info *info) |
| { |
| struct bpf_perf_link *perf_link; |
| const struct perf_event *event; |
| |
| perf_link = container_of(link, struct bpf_perf_link, link); |
| event = perf_get_event(perf_link->perf_file); |
| if (IS_ERR(event)) |
| return PTR_ERR(event); |
| |
| switch (event->prog->type) { |
| case BPF_PROG_TYPE_PERF_EVENT: |
| return bpf_perf_link_fill_perf_event(event, info); |
| case BPF_PROG_TYPE_TRACEPOINT: |
| return bpf_perf_link_fill_tracepoint(event, info); |
| case BPF_PROG_TYPE_KPROBE: |
| return bpf_perf_link_fill_probe(event, info); |
| default: |
| return -EOPNOTSUPP; |
| } |
| } |
| |
| static const struct bpf_link_ops bpf_perf_link_lops = { |
| .release = bpf_perf_link_release, |
| .dealloc = bpf_perf_link_dealloc, |
| .fill_link_info = bpf_perf_link_fill_link_info, |
| }; |
| |
| static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) |
| { |
| struct bpf_link_primer link_primer; |
| struct bpf_perf_link *link; |
| struct perf_event *event; |
| struct file *perf_file; |
| int err; |
| |
| if (attr->link_create.flags) |
| return -EINVAL; |
| |
| perf_file = perf_event_get(attr->link_create.target_fd); |
| if (IS_ERR(perf_file)) |
| return PTR_ERR(perf_file); |
| |
| link = kzalloc(sizeof(*link), GFP_USER); |
| if (!link) { |
| err = -ENOMEM; |
| goto out_put_file; |
| } |
| bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog); |
| link->perf_file = perf_file; |
| |
| err = bpf_link_prime(&link->link, &link_primer); |
| if (err) { |
| kfree(link); |
| goto out_put_file; |
| } |
| |
| event = perf_file->private_data; |
| err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie); |
| if (err) { |
| bpf_link_cleanup(&link_primer); |
| goto out_put_file; |
| } |
| /* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */ |
| bpf_prog_inc(prog); |
| |
| return bpf_link_settle(&link_primer); |
| |
| out_put_file: |
| fput(perf_file); |
| return err; |
| } |
| #else |
| static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) |
| { |
| return -EOPNOTSUPP; |
| } |
| #endif /* CONFIG_PERF_EVENTS */ |
| |
| static int bpf_raw_tp_link_attach(struct bpf_prog *prog, |
| const char __user *user_tp_name, u64 cookie) |
| { |
| struct bpf_link_primer link_primer; |
| struct bpf_raw_tp_link *link; |
| struct bpf_raw_event_map *btp; |
| const char *tp_name; |
| char buf[128]; |
| int err; |
| |
| switch (prog->type) { |
| case BPF_PROG_TYPE_TRACING: |
| case BPF_PROG_TYPE_EXT: |
| case BPF_PROG_TYPE_LSM: |
| if (user_tp_name) |
| /* The attach point for this category of programs |
| * should be specified via btf_id during program load. |
| */ |
| return -EINVAL; |
| if (prog->type == BPF_PROG_TYPE_TRACING && |
| prog->expected_attach_type == BPF_TRACE_RAW_TP) { |
| tp_name = prog->aux->attach_func_name; |
| break; |
| } |
| return bpf_tracing_prog_attach(prog, 0, 0, 0); |
| case BPF_PROG_TYPE_RAW_TRACEPOINT: |
| case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: |
| if (strncpy_from_user(buf, user_tp_name, sizeof(buf) - 1) < 0) |
| return -EFAULT; |
| buf[sizeof(buf) - 1] = 0; |
| tp_name = buf; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| btp = bpf_get_raw_tracepoint(tp_name); |
| if (!btp) |
| return -ENOENT; |
| |
| link = kzalloc(sizeof(*link), GFP_USER); |
| if (!link) { |
| err = -ENOMEM; |
| goto out_put_btp; |
| } |
| bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT, |
| &bpf_raw_tp_link_lops, prog); |
| link->btp = btp; |
| link->cookie = cookie; |
| |
| err = bpf_link_prime(&link->link, &link_primer); |
| if (err) { |
| kfree(link); |
| goto out_put_btp; |
| } |
| |
| err = bpf_probe_register(link->btp, link); |
| if (err) { |
| bpf_link_cleanup(&link_primer); |
| goto out_put_btp; |
| } |
| |
| return bpf_link_settle(&link_primer); |
| |
| out_put_btp: |
| bpf_put_raw_tracepoint(btp); |
| return err; |
| } |
| |
| #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.cookie |
| |
| static int bpf_raw_tracepoint_open(const union bpf_attr *attr) |
| { |
| struct bpf_prog *prog; |
| void __user *tp_name; |
| __u64 cookie; |
| int fd; |
| |
| if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN)) |
| return -EINVAL; |
| |
| prog = bpf_prog_get(attr->raw_tracepoint.prog_fd); |
| if (IS_ERR(prog)) |
| return PTR_ERR(prog); |
| |
| tp_name = u64_to_user_ptr(attr->raw_tracepoint.name); |
| cookie = attr->raw_tracepoint.cookie; |
| fd = bpf_raw_tp_link_attach(prog, tp_name, cookie); |
| if (fd < 0) |
| bpf_prog_put(prog); |
| return fd; |
| } |
| |
| static enum bpf_prog_type |
| attach_type_to_prog_type(enum bpf_attach_type attach_type) |
| { |
| switch (attach_type) { |
| case BPF_CGROUP_INET_INGRESS: |
| case BPF_CGROUP_INET_EGRESS: |
| return BPF_PROG_TYPE_CGROUP_SKB; |
| case BPF_CGROUP_INET_SOCK_CREATE: |
| case BPF_CGROUP_INET_SOCK_RELEASE: |
| case BPF_CGROUP_INET4_POST_BIND: |
| case BPF_CGROUP_INET6_POST_BIND: |
| return BPF_PROG_TYPE_CGROUP_SOCK; |
| case BPF_CGROUP_INET4_BIND: |
| case BPF_CGROUP_INET6_BIND: |
| case BPF_CGROUP_INET4_CONNECT: |
| case BPF_CGROUP_INET6_CONNECT: |
| case BPF_CGROUP_UNIX_CONNECT: |
| case BPF_CGROUP_INET4_GETPEERNAME: |
| case BPF_CGROUP_INET6_GETPEERNAME: |
| case BPF_CGROUP_UNIX_GETPEERNAME: |
| case BPF_CGROUP_INET4_GETSOCKNAME: |
| case BPF_CGROUP_INET6_GETSOCKNAME: |
| case BPF_CGROUP_UNIX_GETSOCKNAME: |
| case BPF_CGROUP_UDP4_SENDMSG: |
| case BPF_CGROUP_UDP6_SENDMSG: |
| case BPF_CGROUP_UNIX_SENDMSG: |
| case BPF_CGROUP_UDP4_RECVMSG: |
| case BPF_CGROUP_UDP6_RECVMSG: |
| case BPF_CGROUP_UNIX_RECVMSG: |
| return BPF_PROG_TYPE_CGROUP_SOCK_ADDR; |
| case BPF_CGROUP_SOCK_OPS: |
| return BPF_PROG_TYPE_SOCK_OPS; |
| case BPF_CGROUP_DEVICE: |
| return BPF_PROG_TYPE_CGROUP_DEVICE; |
| case BPF_SK_MSG_VERDICT: |
| return BPF_PROG_TYPE_SK_MSG; |
| case BPF_SK_SKB_STREAM_PARSER: |
| case BPF_SK_SKB_STREAM_VERDICT: |
| case BPF_SK_SKB_VERDICT: |
| return BPF_PROG_TYPE_SK_SKB; |
| case BPF_LIRC_MODE2: |
| return BPF_PROG_TYPE_LIRC_MODE2; |
| case BPF_FLOW_DISSECTOR: |
| return BPF_PROG_TYPE_FLOW_DISSECTOR; |
| case BPF_CGROUP_SYSCTL: |
| return BPF_PROG_TYPE_CGROUP_SYSCTL; |
| case BPF_CGROUP_GETSOCKOPT: |
| case BPF_CGROUP_SETSOCKOPT: |
| return BPF_PROG_TYPE_CGROUP_SOCKOPT; |
| case BPF_TRACE_ITER: |
| case BPF_TRACE_RAW_TP: |
| case BPF_TRACE_FENTRY: |
| case BPF_TRACE_FEXIT: |
| case BPF_MODIFY_RETURN: |
| return BPF_PROG_TYPE_TRACING; |
| case BPF_LSM_MAC: |
| return BPF_PROG_TYPE_LSM; |
| case BPF_SK_LOOKUP: |
| return BPF_PROG_TYPE_SK_LOOKUP; |
| case BPF_XDP: |
| return BPF_PROG_TYPE_XDP; |
| case BPF_LSM_CGROUP: |
| return BPF_PROG_TYPE_LSM; |
| case BPF_TCX_INGRESS: |
| case BPF_TCX_EGRESS: |
| case BPF_NETKIT_PRIMARY: |
| case BPF_NETKIT_PEER: |
| return BPF_PROG_TYPE_SCHED_CLS; |
| default: |
| return BPF_PROG_TYPE_UNSPEC; |
| } |
| } |
| |
| static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, |
| enum bpf_attach_type attach_type) |
| { |
| enum bpf_prog_type ptype; |
| |
| switch (prog->type) { |
| case BPF_PROG_TYPE_CGROUP_SOCK: |
| case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: |
| case BPF_PROG_TYPE_CGROUP_SOCKOPT: |
| case BPF_PROG_TYPE_SK_LOOKUP: |
| return attach_type == prog->expected_attach_type ? 0 : -EINVAL; |
| case BPF_PROG_TYPE_CGROUP_SKB: |
| if (!bpf_token_capable(prog->aux->token, CAP_NET_ADMIN)) |
| /* cg-skb progs can be loaded by unpriv user. |
| * check permissions at attach time. |
| */ |
| return -EPERM; |
| |
| ptype = attach_type_to_prog_type(attach_type); |
| if (prog->type != ptype) |
| return -EINVAL; |
| |
| return prog->enforce_expected_attach_type && |
| prog->expected_attach_type != attach_type ? |
| -EINVAL : 0; |
| case BPF_PROG_TYPE_EXT: |
| return 0; |
| case BPF_PROG_TYPE_NETFILTER: |
| if (attach_type != BPF_NETFILTER) |
| return -EINVAL; |
| return 0; |
| case BPF_PROG_TYPE_PERF_EVENT: |
| case BPF_PROG_TYPE_TRACEPOINT: |
| if (attach_type != BPF_PERF_EVENT) |
| return -EINVAL; |
| return 0; |
| case BPF_PROG_TYPE_KPROBE: |
| if (prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI && |
| attach_type != BPF_TRACE_KPROBE_MULTI) |
| return -EINVAL; |
| if (prog->expected_attach_type == BPF_TRACE_KPROBE_SESSION && |
| attach_type != BPF_TRACE_KPROBE_SESSION) |
| return -EINVAL; |
| if (prog->expected_attach_type == BPF_TRACE_UPROBE_MULTI && |
| attach_type != BPF_TRACE_UPROBE_MULTI) |
| return -EINVAL; |
| if (attach_type != BPF_PERF_EVENT && |
| attach_type != BPF_TRACE_KPROBE_MULTI && |
| attach_type != BPF_TRACE_KPROBE_SESSION && |
| attach_type != BPF_TRACE_UPROBE_MULTI) |
| return -EINVAL; |
| return 0; |
| case BPF_PROG_TYPE_SCHED_CLS: |
| if (attach_type != BPF_TCX_INGRESS && |
| attach_type != BPF_TCX_EGRESS && |
| attach_type != BPF_NETKIT_PRIMARY && |
| attach_type != BPF_NETKIT_PEER) |
| return -EINVAL; |
| return 0; |
| default: |
| ptype = attach_type_to_prog_type(attach_type); |
| if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) |
| return -EINVAL; |
| return 0; |
| } |
| } |
| |
| #define BPF_PROG_ATTACH_LAST_FIELD expected_revision |
| |
| #define BPF_F_ATTACH_MASK_BASE \ |
| (BPF_F_ALLOW_OVERRIDE | \ |
| BPF_F_ALLOW_MULTI | \ |
| BPF_F_REPLACE) |
| |
| #define BPF_F_ATTACH_MASK_MPROG \ |
| (BPF_F_REPLACE | \ |
| BPF_F_BEFORE | \ |
| BPF_F_AFTER | \ |
| BPF_F_ID | \ |
| BPF_F_LINK) |
| |
| static int bpf_prog_attach(const union bpf_attr *attr) |
| { |
| enum bpf_prog_type ptype; |
| struct bpf_prog *prog; |
| int ret; |
| |
| if (CHECK_ATTR(BPF_PROG_ATTACH)) |
| return -EINVAL; |
| |
| ptype = attach_type_to_prog_type(attr->attach_type); |
| if (ptype == BPF_PROG_TYPE_UNSPEC) |
| return -EINVAL; |
| if (bpf_mprog_supported(ptype)) { |
| if (attr->attach_flags & ~BPF_F_ATTACH_MASK_MPROG) |
| return -EINVAL; |
| } else { |
| if (attr->attach_flags & ~BPF_F_ATTACH_MASK_BASE) |
| return -EINVAL; |
| if (attr->relative_fd || |
| attr->expected_revision) |
| return -EINVAL; |
| } |
| |
| prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); |
| if (IS_ERR(prog)) |
| return PTR_ERR(prog); |
| |
| if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) { |
| bpf_prog_put(prog); |
| return -EINVAL; |
| } |
| |
| switch (ptype) { |
| case BPF_PROG_TYPE_SK_SKB: |
| case BPF_PROG_TYPE_SK_MSG: |
| ret = sock_map_get_from_fd(attr, prog); |
| break; |
| case BPF_PROG_TYPE_LIRC_MODE2: |
| ret = lirc_prog_attach(attr, prog); |
| break; |
| case BPF_PROG_TYPE_FLOW_DISSECTOR: |
| ret = netns_bpf_prog_attach(attr, prog); |
| break; |
| case BPF_PROG_TYPE_CGROUP_DEVICE: |
| case BPF_PROG_TYPE_CGROUP_SKB: |
| case BPF_PROG_TYPE_CGROUP_SOCK: |
| case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: |
| case BPF_PROG_TYPE_CGROUP_SOCKOPT: |
| case BPF_PROG_TYPE_CGROUP_SYSCTL: |
| case BPF_PROG_TYPE_SOCK_OPS: |
| case BPF_PROG_TYPE_LSM: |
| if (ptype == BPF_PROG_TYPE_LSM && |
| prog->expected_attach_type != BPF_LSM_CGROUP) |
| ret = -EINVAL; |
| else |
| ret = cgroup_bpf_prog_attach(attr, ptype, prog); |
| break; |
| case BPF_PROG_TYPE_SCHED_CLS: |
| if (attr->attach_type == BPF_TCX_INGRESS || |
| attr->attach_type == BPF_TCX_EGRESS) |
| ret = tcx_prog_attach(attr, prog); |
| else |
| ret = netkit_prog_attach(attr, prog); |
| break; |
| default: |
| ret = -EINVAL; |
| } |
| |
| if (ret) |
| bpf_prog_put(prog); |
| return ret; |
| } |
| |
| #define BPF_PROG_DETACH_LAST_FIELD expected_revision |
| |
| static int bpf_prog_detach(const union bpf_attr *attr) |
| { |
| struct bpf_prog *prog = NULL; |
| enum bpf_prog_type ptype; |
| int ret; |
| |
| if (CHECK_ATTR(BPF_PROG_DETACH)) |
| return -EINVAL; |
| |
| ptype = attach_type_to_prog_type(attr->attach_type); |
| if (bpf_mprog_supported(ptype)) { |
| if (ptype == BPF_PROG_TYPE_UNSPEC) |
| return -EINVAL; |
| if (attr->attach_flags & ~BPF_F_ATTACH_MASK_MPROG) |
| return -EINVAL; |
| if (attr->attach_bpf_fd) { |
| prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); |
| if (IS_ERR(prog)) |
| return PTR_ERR(prog); |
| } |
| } else if (attr->attach_flags || |
| attr->relative_fd || |
| attr->expected_revision) { |
| return -EINVAL; |
| } |
| |
| switch (ptype) { |
| case BPF_PROG_TYPE_SK_MSG: |
| case BPF_PROG_TYPE_SK_SKB: |
| ret = sock_map_prog_detach(attr, ptype); |
| break; |
| case BPF_PROG_TYPE_LIRC_MODE2: |
| ret = lirc_prog_detach(attr); |
| break; |
| case BPF_PROG_TYPE_FLOW_DISSECTOR: |
| ret = netns_bpf_prog_detach(attr, ptype); |
| break; |
| case BPF_PROG_TYPE_CGROUP_DEVICE: |
| case BPF_PROG_TYPE_CGROUP_SKB: |
| case BPF_PROG_TYPE_CGROUP_SOCK: |
| case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: |
| case BPF_PROG_TYPE_CGROUP_SOCKOPT: |
| case BPF_PROG_TYPE_CGROUP_SYSCTL: |
| case BPF_PROG_TYPE_SOCK_OPS: |
| case BPF_PROG_TYPE_LSM: |
| ret = cgroup_bpf_prog_detach(attr, ptype); |
| break; |
| case BPF_PROG_TYPE_SCHED_CLS: |
| if (attr->attach_type == BPF_TCX_INGRESS || |
| attr->attach_type == BPF_TCX_EGRESS) |
| ret = tcx_prog_detach(attr, prog); |
| else |
| ret = netkit_prog_detach(attr, prog); |
| break; |
| default: |
| ret = -EINVAL; |
| } |
| |
| if (prog) |
| bpf_prog_put(prog); |
| return ret; |
| } |
| |
| #define BPF_PROG_QUERY_LAST_FIELD query.revision |
| |
| static int bpf_prog_query(const union bpf_attr *attr, |
| union bpf_attr __user *uattr) |
| { |
| if (!bpf_net_capable()) |
| return -EPERM; |
| if (CHECK_ATTR(BPF_PROG_QUERY)) |
| return -EINVAL; |
| if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE) |
| return -EINVAL; |
| |
| switch (attr->query.attach_type) { |
| case BPF_CGROUP_INET_INGRESS: |
| case BPF_CGROUP_INET_EGRESS: |
| case BPF_CGROUP_INET_SOCK_CREATE: |
| case BPF_CGROUP_INET_SOCK_RELEASE: |
| case BPF_CGROUP_INET4_BIND: |
| case BPF_CGROUP_INET6_BIND: |
| case BPF_CGROUP_INET4_POST_BIND: |
| case BPF_CGROUP_INET6_POST_BIND: |
| case BPF_CGROUP_INET4_CONNECT: |
| case BPF_CGROUP_INET6_CONNECT: |
| case BPF_CGROUP_UNIX_CONNECT: |
| case BPF_CGROUP_INET4_GETPEERNAME: |
| case BPF_CGROUP_INET6_GETPEERNAME: |
| case BPF_CGROUP_UNIX_GETPEERNAME: |
| case BPF_CGROUP_INET4_GETSOCKNAME: |
| case BPF_CGROUP_INET6_GETSOCKNAME: |
| case BPF_CGROUP_UNIX_GETSOCKNAME: |
| case BPF_CGROUP_UDP4_SENDMSG: |
| case BPF_CGROUP_UDP6_SENDMSG: |
| case BPF_CGROUP_UNIX_SENDMSG: |
| case BPF_CGROUP_UDP4_RECVMSG: |
| case BPF_CGROUP_UDP6_RECVMSG: |
| case BPF_CGROUP_UNIX_RECVMSG: |
| case BPF_CGROUP_SOCK_OPS: |
| case BPF_CGROUP_DEVICE: |
| case BPF_CGROUP_SYSCTL: |
| case BPF_CGROUP_GETSOCKOPT: |
| case BPF_CGROUP_SETSOCKOPT: |
| case BPF_LSM_CGROUP: |
| return cgroup_bpf_prog_query(attr, uattr); |
| case BPF_LIRC_MODE2: |
| return lirc_prog_query(attr, uattr); |
| case BPF_FLOW_DISSECTOR: |
| case BPF_SK_LOOKUP: |
| return netns_bpf_prog_query(attr, uattr); |
| case BPF_SK_SKB_STREAM_PARSER: |
| case BPF_SK_SKB_STREAM_VERDICT: |
| case BPF_SK_MSG_VERDICT: |
| case BPF_SK_SKB_VERDICT: |
| return sock_map_bpf_prog_query(attr, uattr); |
| case BPF_TCX_INGRESS: |
| case BPF_TCX_EGRESS: |
| return tcx_prog_query(attr, uattr); |
| case BPF_NETKIT_PRIMARY: |
| case BPF_NETKIT_PEER: |
| return netkit_prog_query(attr, uattr); |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| #define BPF_PROG_TEST_RUN_LAST_FIELD test.batch_size |
| |
| static int bpf_prog_test_run(const union bpf_attr *attr, |
| union bpf_attr __user *uattr) |
| { |
| struct bpf_prog *prog; |
| int ret = -ENOTSUPP; |
| |
| if (CHECK_ATTR(BPF_PROG_TEST_RUN)) |
| return -EINVAL; |
| |
| if ((attr->test.ctx_size_in && !attr->test.ctx_in) || |
| (!attr->test.ctx_size_in && attr->test.ctx_in)) |
| return -EINVAL; |
| |
| if ((attr->test.ctx_size_out && !attr->test.ctx_out) || |
| (!attr->test.ctx_size_out && attr->test.ctx_out)) |
| return -EINVAL; |
| |
| prog = bpf_prog_get(attr->test.prog_fd); |
| if (IS_ERR(prog)) |
| return PTR_ERR(prog); |
| |
| if (prog->aux->ops->test_run) |
| ret = prog->aux->ops->test_run(prog, attr, uattr); |
| |
| bpf_prog_put(prog); |
| return ret; |
| } |
| |
| #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id |
| |
| static int bpf_obj_get_next_id(const union bpf_attr *attr, |
| union bpf_attr __user *uattr, |
| struct idr *idr, |
| spinlock_t *lock) |
| { |
| u32 next_id = attr->start_id; |
| int err = 0; |
| |
| if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) |
| return -EINVAL; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| next_id++; |
| spin_lock_bh(lock); |
| if (!idr_get_next(idr, &next_id)) |
| err = -ENOENT; |
| spin_unlock_bh(lock); |
| |
| if (!err) |
| err = put_user(next_id, &uattr->next_id); |
| |
| return err; |
| } |
| |
| struct bpf_map *bpf_map_get_curr_or_next(u32 *id) |
| { |
| struct bpf_map *map; |
| |
| spin_lock_bh(&map_idr_lock); |
| again: |
| map = idr_get_next(&map_idr, id); |
| if (map) { |
| map = __bpf_map_inc_not_zero(map, false); |
| if (IS_ERR(map)) { |
| (*id)++; |
| goto again; |
| } |
| } |
| spin_unlock_bh(&map_idr_lock); |
| |
| return map; |
| } |
| |
| struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id) |
| { |
| struct bpf_prog *prog; |
| |
| spin_lock_bh(&prog_idr_lock); |
| again: |
| prog = idr_get_next(&prog_idr, id); |
| if (prog) { |
| prog = bpf_prog_inc_not_zero(prog); |
| if (IS_ERR(prog)) { |
| (*id)++; |
| goto again; |
| } |
| } |
| spin_unlock_bh(&prog_idr_lock); |
| |
| return prog; |
| } |
| |
| #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id |
| |
| struct bpf_prog *bpf_prog_by_id(u32 id) |
| { |
| struct bpf_prog *prog; |
| |
| if (!id) |
| return ERR_PTR(-ENOENT); |
| |
| spin_lock_bh(&prog_idr_lock); |
| prog = idr_find(&prog_idr, id); |
| if (prog) |
| prog = bpf_prog_inc_not_zero(prog); |
| else |
| prog = ERR_PTR(-ENOENT); |
| spin_unlock_bh(&prog_idr_lock); |
| return prog; |
| } |
| |
| static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) |
| { |
| struct bpf_prog *prog; |
| u32 id = attr->prog_id; |
| int fd; |
| |
| if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) |
| return -EINVAL; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| prog = bpf_prog_by_id(id); |
| if (IS_ERR(prog)) |
| return PTR_ERR(prog); |
| |
| fd = bpf_prog_new_fd(prog); |
| if (fd < 0) |
| bpf_prog_put(prog); |
| |
| return fd; |
| } |
| |
| #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags |
| |
| static int bpf_map_get_fd_by_id(const union bpf_attr *attr) |
| { |
| struct bpf_map *map; |
| u32 id = attr->map_id; |
| int f_flags; |
| int fd; |
| |
| if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) || |
| attr->open_flags & ~BPF_OBJ_FLAG_MASK) |
| return -EINVAL; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| f_flags = bpf_get_file_flag(attr->open_flags); |
| if (f_flags < 0) |
| return f_flags; |
| |
| spin_lock_bh(&map_idr_lock); |
| map = idr_find(&map_idr, id); |
| if (map) |
| map = __bpf_map_inc_not_zero(map, true); |
| else |
| map = ERR_PTR(-ENOENT); |
| spin_unlock_bh(&map_idr_lock); |
| |
| if (IS_ERR(map)) |
| return PTR_ERR(map); |
| |
| fd = bpf_map_new_fd(map, f_flags); |
| if (fd < 0) |
| bpf_map_put_with_uref(map); |
| |
| return fd; |
| } |
| |
| static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, |
| unsigned long addr, u32 *off, |
| u32 *type) |
| { |
| const struct bpf_map *map; |
| int i; |
| |
| mutex_lock(&prog->aux->used_maps_mutex); |
| for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) { |
| map = prog->aux->used_maps[i]; |
| if (map == (void *)addr) { |
| *type = BPF_PSEUDO_MAP_FD; |
| goto out; |
| } |
| if (!map->ops->map_direct_value_meta) |
| continue; |
| if (!map->ops->map_direct_value_meta(map, addr, off)) { |
| *type = BPF_PSEUDO_MAP_VALUE; |
| goto out; |
| } |
| } |
| map = NULL; |
| |
| out: |
| mutex_unlock(&prog->aux->used_maps_mutex); |
| return map; |
| } |
| |
| static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog, |
| const struct cred *f_cred) |
| { |
| const struct bpf_map *map; |
| struct bpf_insn *insns; |
| u32 off, type; |
| u64 imm; |
| u8 code; |
| int i; |
| |
| insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), |
| GFP_USER); |
| if (!insns) |
| return insns; |
| |
| for (i = 0; i < prog->len; i++) { |
| code = insns[i].code; |
| |
| if (code == (BPF_JMP | BPF_TAIL_CALL)) { |
| insns[i].code = BPF_JMP | BPF_CALL; |
| insns[i].imm = BPF_FUNC_tail_call; |
| /* fall-through */ |
| } |
| if (code == (BPF_JMP | BPF_CALL) || |
| code == (BPF_JMP | BPF_CALL_ARGS)) { |
| if (code == (BPF_JMP | BPF_CALL_ARGS)) |
| insns[i].code = BPF_JMP | BPF_CALL; |
| if (!bpf_dump_raw_ok(f_cred)) |
| insns[i].imm = 0; |
| continue; |
| } |
| if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) { |
| insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM; |
| continue; |
| } |
| |
| if ((BPF_CLASS(code) == BPF_LDX || BPF_CLASS(code) == BPF_STX || |
| BPF_CLASS(code) == BPF_ST) && BPF_MODE(code) == BPF_PROBE_MEM32) { |
| insns[i].code = BPF_CLASS(code) | BPF_SIZE(code) | BPF_MEM; |
| continue; |
| } |
| |
| if (code != (BPF_LD | BPF_IMM | BPF_DW)) |
| continue; |
| |
| imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; |
| map = bpf_map_from_imm(prog, imm, &off, &type); |
| if (map) { |
| insns[i].src_reg = type; |
| insns[i].imm = map->id; |
| insns[i + 1].imm = off; |
| continue; |
| } |
| } |
| |
| return insns; |
| } |
| |
| static int set_info_rec_size(struct bpf_prog_info *info) |
| { |
| /* |
| * Ensure info.*_rec_size is the same as kernel expected size |
| * |
| * or |
| * |
| * Only allow zero *_rec_size if both _rec_size and _cnt are |
| * zero. In this case, the kernel will set the expected |
| * _rec_size back to the info. |
| */ |
| |
| if ((info->nr_func_info || info->func_info_rec_size) && |
| info->func_info_rec_size != sizeof(struct bpf_func_info)) |
| return -EINVAL; |
| |
| if ((info->nr_line_info || info->line_info_rec_size) && |
| info->line_info_rec_size != sizeof(struct bpf_line_info)) |
| return -EINVAL; |
| |
| if ((info->nr_jited_line_info || info->jited_line_info_rec_size) && |
| info->jited_line_info_rec_size != sizeof(__u64)) |
| return -EINVAL; |
| |
| info->func_info_rec_size = sizeof(struct bpf_func_info); |
| info->line_info_rec_size = sizeof(struct bpf_line_info); |
| info->jited_line_info_rec_size = sizeof(__u64); |
| |
| return 0; |
| } |
| |
| static int bpf_prog_get_info_by_fd(struct file *file, |
| struct bpf_prog *prog, |
| const union bpf_attr *attr, |
| union bpf_attr __user *uattr) |
| { |
| struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); |
| struct btf *attach_btf = bpf_prog_get_target_btf(prog); |
| struct bpf_prog_info info; |
| u32 info_len = attr->info.info_len; |
| struct bpf_prog_kstats stats; |
| char __user *uinsns; |
| u32 ulen; |
| int err; |
| |
| err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); |
| if (err) |
| return err; |
| info_len = min_t(u32, sizeof(info), info_len); |
| |
| memset(&info, 0, sizeof(info)); |
| if (copy_from_user(&info, uinfo, info_len)) |
| return -EFAULT; |
| |
| info.type = prog->type; |
| info.id = prog->aux->id; |
| info.load_time = prog->aux->load_time; |
| info.created_by_uid = from_kuid_munged(current_user_ns(), |
| prog->aux->user->uid); |
| info.gpl_compatible = prog->gpl_compatible; |
| |
| memcpy(info.tag, prog->tag, sizeof(prog->tag)); |
| memcpy(info.name, prog->aux->name, sizeof(prog->aux->name)); |
| |
| mutex_lock(&prog->aux->used_maps_mutex); |
| ulen = info.nr_map_ids; |
| info.nr_map_ids = prog->aux->used_map_cnt; |
| ulen = min_t(u32, info.nr_map_ids, ulen); |
| if (ulen) { |
| u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids); |
| u32 i; |
| |
| for (i = 0; i < ulen; i++) |
| if (put_user(prog->aux->used_maps[i]->id, |
| &user_map_ids[i])) { |
| mutex_unlock(&prog->aux->used_maps_mutex); |
| return -EFAULT; |
| } |
| } |
| mutex_unlock(&prog->aux->used_maps_mutex); |
| |
| err = set_info_rec_size(&info); |
| if (err) |
| return err; |
| |
| bpf_prog_get_stats(prog, &stats); |
| info.run_time_ns = stats.nsecs; |
| info.run_cnt = stats.cnt; |
| info.recursion_misses = stats.misses; |
| |
| info.verified_insns = prog->aux->verified_insns; |
| |
| if (!bpf_capable()) { |
| info.jited_prog_len = 0; |
| info.xlated_prog_len = 0; |
| info.nr_jited_ksyms = 0; |
| info.nr_jited_func_lens = 0; |
| info.nr_func_info = 0; |
| info.nr_line_info = 0; |
| info.nr_jited_line_info = 0; |
| goto done; |
| } |
| |
| ulen = info.xlated_prog_len; |
| info.xlated_prog_len = bpf_prog_insn_size(prog); |
| if (info.xlated_prog_len && ulen) { |
| struct bpf_insn *insns_sanitized; |
| bool fault; |
| |
| if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) { |
| info.xlated_prog_insns = 0; |
| goto done; |
| } |
| insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred); |
| if (!insns_sanitized) |
| return -ENOMEM; |
| uinsns = u64_to_user_ptr(info.xlated_prog_insns); |
| ulen = min_t(u32, info.xlated_prog_len, ulen); |
| fault = copy_to_user(uinsns, insns_sanitized, ulen); |
| kfree(insns_sanitized); |
| if (fault) |
| return -EFAULT; |
| } |
| |
| if (bpf_prog_is_offloaded(prog->aux)) { |
| err = bpf_prog_offload_info_fill(&info, prog); |
| if (err) |
| return err; |
| goto done; |
| } |
| |
| /* NOTE: the following code is supposed to be skipped for offload. |
| * bpf_prog_offload_info_fill() is the place to fill similar fields |
| * for offload. |
| */ |
| ulen = info.jited_prog_len; |
| if (prog->aux->func_cnt) { |
| u32 i; |
| |
| info.jited_prog_len = 0; |
| for (i = 0; i < prog->aux->func_cnt; i++) |
| info.jited_prog_len += prog->aux->func[i]->jited_len; |
| } else { |
| info.jited_prog_len = prog->jited_len; |
| } |
| |
| if (info.jited_prog_len && ulen) { |
| if (bpf_dump_raw_ok(file->f_cred)) { |
| uinsns = u64_to_user_ptr(info.jited_prog_insns); |
| ulen = min_t(u32, info.jited_prog_len, ulen); |
| |
| /* for multi-function programs, copy the JITed |
| * instructions for all the functions |
| */ |
| if (prog->aux->func_cnt) { |
| u32 len, free, i; |
| u8 *img; |
| |
| free = ulen; |
| for (i = 0; i < prog->aux->func_cnt; i++) { |
| len = prog->aux->func[i]->jited_len; |
| len = min_t(u32, len, free); |
| img = (u8 *) prog->aux->func[i]->bpf_func; |
| if (copy_to_user(uinsns, img, len)) |
| return -EFAULT; |
| uinsns += len; |
| free -= len; |
| if (!free) |
| break; |
| } |
| } else { |
| if (copy_to_user(uinsns, prog->bpf_func, ulen)) |
| return -EFAULT; |
| } |
| } else { |
| info.jited_prog_insns = 0; |
| } |
| } |
| |
| ulen = info.nr_jited_ksyms; |
| info.nr_jited_ksyms = prog->aux->func_cnt ? : 1; |
| if (ulen) { |
| if (bpf_dump_raw_ok(file->f_cred)) { |
| unsigned long ksym_addr; |
| u64 __user *user_ksyms; |
| u32 i; |
| |
| /* copy the address of the kernel symbol |
| * corresponding to each function |
| */ |
| ulen = min_t(u32, info.nr_jited_ksyms, ulen); |
| user_ksyms = u64_to_user_ptr(info.jited_ksyms); |
| if (prog->aux->func_cnt) { |
| for (i = 0; i < ulen; i++) { |
| ksym_addr = (unsigned long) |
| prog->aux->func[i]->bpf_func; |
| if (put_user((u64) ksym_addr, |
| &user_ksyms[i])) |
| return -EFAULT; |
| } |
| } else { |
| ksym_addr = (unsigned long) prog->bpf_func; |
| if (put_user((u64) ksym_addr, &user_ksyms[0])) |
| return -EFAULT; |
| } |
| } else { |
| info.jited_ksyms = 0; |
| } |
| } |
| |
| ulen = info.nr_jited_func_lens; |
| info.nr_jited_func_lens = prog->aux->func_cnt ? : 1; |
| if (ulen) { |
| if (bpf_dump_raw_ok(file->f_cred)) { |
| u32 __user *user_lens; |
| u32 func_len, i; |
| |
| /* copy the JITed image lengths for each function */ |
| ulen = min_t(u32, info.nr_jited_func_lens, ulen); |
| user_lens = u64_to_user_ptr(info.jited_func_lens); |
| if (prog->aux->func_cnt) { |
| for (i = 0; i < ulen; i++) { |
| func_len = |
| prog->aux->func[i]->jited_len; |
| if (put_user(func_len, &user_lens[i])) |
| return -EFAULT; |
| } |
| } else { |
| func_len = prog->jited_len; |
| if (put_user(func_len, &user_lens[0])) |
| return -EFAULT; |
| } |
| } else { |
| info.jited_func_lens = 0; |
| } |
| } |
| |
| if (prog->aux->btf) |
| info.btf_id = btf_obj_id(prog->aux->btf); |
| info.attach_btf_id = prog->aux->attach_btf_id; |
| if (attach_btf) |
| info.attach_btf_obj_id = btf_obj_id(attach_btf); |
| |
| ulen = info.nr_func_info; |
| info.nr_func_info = prog->aux->func_info_cnt; |
| if (info.nr_func_info && ulen) { |
| char __user *user_finfo; |
| |
| user_finfo = u64_to_user_ptr(info.func_info); |
| ulen = min_t(u32, info.nr_func_info, ulen); |
| if (copy_to_user(user_finfo, prog->aux->func_info, |
| info.func_info_rec_size * ulen)) |
| return -EFAULT; |
| } |
| |
| ulen = info.nr_line_info; |
| info.nr_line_info = prog->aux->nr_linfo; |
| if (info.nr_line_info && ulen) { |
| __u8 __user *user_linfo; |
| |
| user_linfo = u64_to_user_ptr(info.line_info); |
| ulen = min_t(u32, info.nr_line_info, ulen); |
| if (copy_to_user(user_linfo, prog->aux->linfo, |
| info.line_info_rec_size * ulen)) |
| return -EFAULT; |
| } |
| |
| ulen = info.nr_jited_line_info; |
| if (prog->aux->jited_linfo) |
| info.nr_jited_line_info = prog->aux->nr_linfo; |
| else |
| info.nr_jited_line_info = 0; |
| if (info.nr_jited_line_info && ulen) { |
| if (bpf_dump_raw_ok(file->f_cred)) { |
| unsigned long line_addr; |
| __u64 __user *user_linfo; |
| u32 i; |
| |
| user_linfo = u64_to_user_ptr(info.jited_line_info); |
| ulen = min_t(u32, info.nr_jited_line_info, ulen); |
| for (i = 0; i < ulen; i++) { |
| line_addr = (unsigned long)prog->aux->jited_linfo[i]; |
| if (put_user((__u64)line_addr, &user_linfo[i])) |
| return -EFAULT; |
| } |
| } else { |
| info.jited_line_info = 0; |
| } |
| } |
| |
| ulen = info.nr_prog_tags; |
| info.nr_prog_tags = prog->aux->func_cnt ? : 1; |
| if (ulen) { |
| __u8 __user (*user_prog_tags)[BPF_TAG_SIZE]; |
| u32 i; |
| |
| user_prog_tags = u64_to_user_ptr(info.prog_tags); |
| ulen = min_t(u32, info.nr_prog_tags, ulen); |
| if (prog->aux->func_cnt) { |
| for (i = 0; i < ulen; i++) { |
| if (copy_to_user(user_prog_tags[i], |
| prog->aux->func[i]->tag, |
| BPF_TAG_SIZE)) |
| return -EFAULT; |
| } |
| } else { |
| if (copy_to_user(user_prog_tags[0], |
| prog->tag, BPF_TAG_SIZE)) |
| return -EFAULT; |
| } |
| } |
| |
| done: |
| if (copy_to_user(uinfo, &info, info_len) || |
| put_user(info_len, &uattr->info.info_len)) |
| return -EFAULT; |
| |
| return 0; |
| } |
| |
| static int bpf_map_get_info_by_fd(struct file *file, |
| struct bpf_map *map, |
| const union bpf_attr *attr, |
| union bpf_attr __user *uattr) |
| { |
| struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); |
| struct bpf_map_info info; |
| u32 info_len = attr->info.info_len; |
| int err; |
| |
| err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); |
| if (err) |
| return err; |
| info_len = min_t(u32, sizeof(info), info_len); |
| |
| memset(&info, 0, sizeof(info)); |
| info.type = map->map_type; |
| info.id = map->id; |
| info.key_size = map->key_size; |
| info.value_size = map->value_size; |
| info.max_entries = map->max_entries; |
| info.map_flags = map->map_flags; |
| info.map_extra = map->map_extra; |
| memcpy(info.name, map->name, sizeof(map->name)); |
| |
| if (map->btf) { |
| info.btf_id = btf_obj_id(map->btf); |
| info.btf_key_type_id = map->btf_key_type_id; |
| info.btf_value_type_id = map->btf_value_type_id; |
| } |
| info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id; |
| if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) |
| bpf_map_struct_ops_info_fill(&info, map); |
| |
| if (bpf_map_is_offloaded(map)) { |
| err = bpf_map_offload_info_fill(&info, map); |
| if (err) |
| return err; |
| } |
| |
| if (copy_to_user(uinfo, &info, info_len) || |
| put_user(info_len, &uattr->info.info_len)) |
| return -EFAULT; |
| |
| return 0; |
| } |
| |
| static int bpf_btf_get_info_by_fd(struct file *file, |
| struct btf *btf, |
| const union bpf_attr *attr, |
| union bpf_attr __user *uattr) |
| { |
| struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info); |
| u32 info_len = attr->info.info_len; |
| int err; |
| |
| err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len); |
| if (err) |
| return err; |
| |
| return btf_get_info_by_fd(btf, attr, uattr); |
| } |
| |
| static int bpf_link_get_info_by_fd(struct file *file, |
| struct bpf_link *link, |
| const union bpf_attr *attr, |
| union bpf_attr __user *uattr) |
| { |
| struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info); |
| struct bpf_link_info info; |
| u32 info_len = attr->info.info_len; |
| int err; |
| |
| err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len); |
| if (err) |
| return err; |
| info_len = min_t(u32, sizeof(info), info_len); |
| |
| memset(&info, 0, sizeof(info)); |
| if (copy_from_user(&info, uinfo, info_len)) |
| return -EFAULT; |
| |
| info.type = link->type; |
| info.id = link->id; |
| if (link->prog) |
| info.prog_id = link->prog->aux->id; |
| |
| if (link->ops->fill_link_info) { |
| err = link->ops->fill_link_info(link, &info); |
| if (err) |
| return err; |
| } |
| |
| if (copy_to_user(uinfo, &info, info_len) || |
| put_user(info_len, &uattr->info.info_len)) |
| return -EFAULT; |
| |
| return 0; |
| } |
| |
| |
| #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info |
| |
| static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, |
| union bpf_attr __user *uattr) |
| { |
| if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD)) |
| return -EINVAL; |
| |
| CLASS(fd, f)(attr->info.bpf_fd); |
| if (fd_empty(f)) |
| return -EBADFD; |
| |
| if (fd_file(f)->f_op == &bpf_prog_fops) |
| return bpf_prog_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, |
| uattr); |
| else if (fd_file(f)->f_op == &bpf_map_fops) |
| return bpf_map_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, |
| uattr); |
| else if (fd_file(f)->f_op == &btf_fops) |
| return bpf_btf_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, uattr); |
| else if (fd_file(f)->f_op == &bpf_link_fops || fd_file(f)->f_op == &bpf_link_fops_poll) |
| return bpf_link_get_info_by_fd(fd_file(f), fd_file(f)->private_data, |
| attr, uattr); |
| return -EINVAL; |
| } |
| |
| #define BPF_BTF_LOAD_LAST_FIELD btf_token_fd |
| |
| static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr, __u32 uattr_size) |
| { |
| struct bpf_token *token = NULL; |
| |
| if (CHECK_ATTR(BPF_BTF_LOAD)) |
| return -EINVAL; |
| |
| if (attr->btf_flags & ~BPF_F_TOKEN_FD) |
| return -EINVAL; |
| |
| if (attr->btf_flags & BPF_F_TOKEN_FD) { |
| token = bpf_token_get_from_fd(attr->btf_token_fd); |
| if (IS_ERR(token)) |
| return PTR_ERR(token); |
| if (!bpf_token_allow_cmd(token, BPF_BTF_LOAD)) { |
| bpf_token_put(token); |
| token = NULL; |
| } |
| } |
| |
| if (!bpf_token_capable(token, CAP_BPF)) { |
| bpf_token_put(token); |
| return -EPERM; |
| } |
| |
| bpf_token_put(token); |
| |
| return btf_new_fd(attr, uattr, uattr_size); |
| } |
| |
| #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id |
| |
| static int bpf_btf_get_fd_by_id(const union bpf_attr *attr) |
| { |
| if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID)) |
| return -EINVAL; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| return btf_get_fd_by_id(attr->btf_id); |
| } |
| |
| static int bpf_task_fd_query_copy(const union bpf_attr *attr, |
| union bpf_attr __user *uattr, |
| u32 prog_id, u32 fd_type, |
| const char *buf, u64 probe_offset, |
| u64 probe_addr) |
| { |
| char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf); |
| u32 len = buf ? strlen(buf) : 0, input_len; |
| int err = 0; |
| |
| if (put_user(len, &uattr->task_fd_query.buf_len)) |
| return -EFAULT; |
| input_len = attr->task_fd_query.buf_len; |
| if (input_len && ubuf) { |
| if (!len) { |
| /* nothing to copy, just make ubuf NULL terminated */ |
| char zero = '\0'; |
| |
| if (put_user(zero, ubuf)) |
| return -EFAULT; |
| } else if (input_len >= len + 1) { |
| /* ubuf can hold the string with NULL terminator */ |
| if (copy_to_user(ubuf, buf, len + 1)) |
| return -EFAULT; |
| } else { |
| /* ubuf cannot hold the string with NULL terminator, |
| * do a partial copy with NULL terminator. |
| */ |
| char zero = '\0'; |
| |
| err = -ENOSPC; |
| if (copy_to_user(ubuf, buf, input_len - 1)) |
| return -EFAULT; |
| if (put_user(zero, ubuf + input_len - 1)) |
| return -EFAULT; |
| } |
| } |
| |
| if (put_user(prog_id, &uattr->task_fd_query.prog_id) || |
| put_user(fd_type, &uattr->task_fd_query.fd_type) || |
| put_user(probe_offset, &uattr->task_fd_query.probe_offset) || |
| put_user(probe_addr, &uattr->task_fd_query.probe_addr)) |
| return -EFAULT; |
| |
| return err; |
| } |
| |
| #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr |
| |
| static int bpf_task_fd_query(const union bpf_attr *attr, |
| union bpf_attr __user *uattr) |
| { |
| pid_t pid = attr->task_fd_query.pid; |
| u32 fd = attr->task_fd_query.fd; |
| const struct perf_event *event; |
| struct task_struct *task; |
| struct file *file; |
| int err; |
| |
| if (CHECK_ATTR(BPF_TASK_FD_QUERY)) |
| return -EINVAL; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| if (attr->task_fd_query.flags != 0) |
| return -EINVAL; |
| |
| rcu_read_lock(); |
| task = get_pid_task(find_vpid(pid), PIDTYPE_PID); |
| rcu_read_unlock(); |
| if (!task) |
| return -ENOENT; |
| |
| err = 0; |
| file = fget_task(task, fd); |
| put_task_struct(task); |
| if (!file) |
| return -EBADF; |
| |
| if (file->f_op == &bpf_link_fops || file->f_op == &bpf_link_fops_poll) { |
| struct bpf_link *link = file->private_data; |
| |
| if (link->ops == &bpf_raw_tp_link_lops) { |
| struct bpf_raw_tp_link *raw_tp = |
| container_of(link, struct bpf_raw_tp_link, link); |
| struct bpf_raw_event_map *btp = raw_tp->btp; |
| |
| err = bpf_task_fd_query_copy(attr, uattr, |
| raw_tp->link.prog->aux->id, |
| BPF_FD_TYPE_RAW_TRACEPOINT, |
| btp->tp->name, 0, 0); |
| goto put_file; |
| } |
| goto out_not_supp; |
| } |
| |
| event = perf_get_event(file); |
| if (!IS_ERR(event)) { |
| u64 probe_offset, probe_addr; |
| u32 prog_id, fd_type; |
| const char *buf; |
| |
| err = bpf_get_perf_event_info(event, &prog_id, &fd_type, |
| &buf, &probe_offset, |
| &probe_addr, NULL); |
| if (!err) |
| err = bpf_task_fd_query_copy(attr, uattr, prog_id, |
| fd_type, buf, |
| probe_offset, |
| probe_addr); |
| goto put_file; |
| } |
| |
| out_not_supp: |
| err = -ENOTSUPP; |
| put_file: |
| fput(file); |
| return err; |
| } |
| |
| #define BPF_MAP_BATCH_LAST_FIELD batch.flags |
| |
| #define BPF_DO_BATCH(fn, ...) \ |
| do { \ |
| if (!fn) { \ |
| err = -ENOTSUPP; \ |
| goto err_put; \ |
| } \ |
| err = fn(__VA_ARGS__); \ |
| } while (0) |
| |
| static int bpf_map_do_batch(const union bpf_attr *attr, |
| union bpf_attr __user *uattr, |
| int cmd) |
| { |
| bool has_read = cmd == BPF_MAP_LOOKUP_BATCH || |
| cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH; |
| bool has_write = cmd != BPF_MAP_LOOKUP_BATCH; |
| struct bpf_map *map; |
| int err; |
| |
| if (CHECK_ATTR(BPF_MAP_BATCH)) |
| return -EINVAL; |
| |
| CLASS(fd, f)(attr->batch.map_fd); |
| |
| map = __bpf_map_get(f); |
| if (IS_ERR(map)) |
| return PTR_ERR(map); |
| if (has_write) |
| bpf_map_write_active_inc(map); |
| if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) { |
| err = -EPERM; |
| goto err_put; |
| } |
| if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { |
| err = -EPERM; |
| goto err_put; |
| } |
| |
| if (cmd == BPF_MAP_LOOKUP_BATCH) |
| BPF_DO_BATCH(map->ops->map_lookup_batch, map, attr, uattr); |
| else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) |
| BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch, map, attr, uattr); |
| else if (cmd == BPF_MAP_UPDATE_BATCH) |
| BPF_DO_BATCH(map->ops->map_update_batch, map, fd_file(f), attr, uattr); |
| else |
| BPF_DO_BATCH(map->ops->map_delete_batch, map, attr, uattr); |
| err_put: |
| if (has_write) { |
| maybe_wait_bpf_programs(map); |
| bpf_map_write_active_dec(map); |
| } |
| return err; |
| } |
| |
| #define BPF_LINK_CREATE_LAST_FIELD link_create.uprobe_multi.pid |
| static int link_create(union bpf_attr *attr, bpfptr_t uattr) |
| { |
| struct bpf_prog *prog; |
| int ret; |
| |
| if (CHECK_ATTR(BPF_LINK_CREATE)) |
| return -EINVAL; |
| |
| if (attr->link_create.attach_type == BPF_STRUCT_OPS) |
| return bpf_struct_ops_link_create(attr); |
| |
| prog = bpf_prog_get(attr->link_create.prog_fd); |
| if (IS_ERR(prog)) |
| return PTR_ERR(prog); |
| |
| ret = bpf_prog_attach_check_attach_type(prog, |
| attr->link_create.attach_type); |
| if (ret) |
| goto out; |
| |
| switch (prog->type) { |
| case BPF_PROG_TYPE_CGROUP_SKB: |
| case BPF_PROG_TYPE_CGROUP_SOCK: |
| case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: |
| case BPF_PROG_TYPE_SOCK_OPS: |
| case BPF_PROG_TYPE_CGROUP_DEVICE: |
| case BPF_PROG_TYPE_CGROUP_SYSCTL: |
| case BPF_PROG_TYPE_CGROUP_SOCKOPT: |
| ret = cgroup_bpf_link_attach(attr, prog); |
| break; |
| case BPF_PROG_TYPE_EXT: |
| ret = bpf_tracing_prog_attach(prog, |
| attr->link_create.target_fd, |
| attr->link_create.target_btf_id, |
| attr->link_create.tracing.cookie); |
| break; |
| case BPF_PROG_TYPE_LSM: |
| case BPF_PROG_TYPE_TRACING: |
| if (attr->link_create.attach_type != prog->expected_attach_type) { |
| ret = -EINVAL; |
| goto out; |
| } |
| if (prog->expected_attach_type == BPF_TRACE_RAW_TP) |
| ret = bpf_raw_tp_link_attach(prog, NULL, attr->link_create.tracing.cookie); |
| else if (prog->expected_attach_type == BPF_TRACE_ITER) |
| ret = bpf_iter_link_attach(attr, uattr, prog); |
| else if (prog->expected_attach_type == BPF_LSM_CGROUP) |
| ret = cgroup_bpf_link_attach(attr, prog); |
| else |
| ret = bpf_tracing_prog_attach(prog, |
| attr->link_create.target_fd, |
| attr->link_create.target_btf_id, |
| attr->link_create.tracing.cookie); |
| break; |
| case BPF_PROG_TYPE_FLOW_DISSECTOR: |
| case BPF_PROG_TYPE_SK_LOOKUP: |
| ret = netns_bpf_link_create(attr, prog); |
| break; |
| case BPF_PROG_TYPE_SK_MSG: |
| case BPF_PROG_TYPE_SK_SKB: |
| ret = sock_map_link_create(attr, prog); |
| break; |
| #ifdef CONFIG_NET |
| case BPF_PROG_TYPE_XDP: |
| ret = bpf_xdp_link_attach(attr, prog); |
| break; |
| case BPF_PROG_TYPE_SCHED_CLS: |
| if (attr->link_create.attach_type == BPF_TCX_INGRESS || |
| attr->link_create.attach_type == BPF_TCX_EGRESS) |
| ret = tcx_link_attach(attr, prog); |
| else |
| ret = netkit_link_attach(attr, prog); |
| break; |
| case BPF_PROG_TYPE_NETFILTER: |
| ret = bpf_nf_link_attach(attr, prog); |
| break; |
| #endif |
| case BPF_PROG_TYPE_PERF_EVENT: |
| case BPF_PROG_TYPE_TRACEPOINT: |
| ret = bpf_perf_link_attach(attr, prog); |
| break; |
| case BPF_PROG_TYPE_KPROBE: |
| if (attr->link_create.attach_type == BPF_PERF_EVENT) |
| ret = bpf_perf_link_attach(attr, prog); |
| else if (attr->link_create.attach_type == BPF_TRACE_KPROBE_MULTI || |
| attr->link_create.attach_type == BPF_TRACE_KPROBE_SESSION) |
| ret = bpf_kprobe_multi_link_attach(attr, prog); |
| else if (attr->link_create.attach_type == BPF_TRACE_UPROBE_MULTI) |
| ret = bpf_uprobe_multi_link_attach(attr, prog); |
| break; |
| default: |
| ret = -EINVAL; |
| } |
| |
| out: |
| if (ret < 0) |
| bpf_prog_put(prog); |
| return ret; |
| } |
| |
| static int link_update_map(struct bpf_link *link, union bpf_attr *attr) |
| { |
| struct bpf_map *new_map, *old_map = NULL; |
| int ret; |
| |
| new_map = bpf_map_get(attr->link_update.new_map_fd); |
| if (IS_ERR(new_map)) |
| return PTR_ERR(new_map); |
| |
| if (attr->link_update.flags & BPF_F_REPLACE) { |
| old_map = bpf_map_get(attr->link_update.old_map_fd); |
| if (IS_ERR(old_map)) { |
| ret = PTR_ERR(old_map); |
| goto out_put; |
| } |
| } else if (attr->link_update.old_map_fd) { |
| ret = -EINVAL; |
| goto out_put; |
| } |
| |
| ret = link->ops->update_map(link, new_map, old_map); |
| |
| if (old_map) |
| bpf_map_put(old_map); |
| out_put: |
| bpf_map_put(new_map); |
| return ret; |
| } |
| |
| #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd |
| |
| static int link_update(union bpf_attr *attr) |
| { |
| struct bpf_prog *old_prog = NULL, *new_prog; |
| struct bpf_link *link; |
| u32 flags; |
| int ret; |
| |
| if (CHECK_ATTR(BPF_LINK_UPDATE)) |
| return -EINVAL; |
| |
| flags = attr->link_update.flags; |
| if (flags & ~BPF_F_REPLACE) |
| return -EINVAL; |
| |
| link = bpf_link_get_from_fd(attr->link_update.link_fd); |
| if (IS_ERR(link)) |
| return PTR_ERR(link); |
| |
| if (link->ops->update_map) { |
| ret = link_update_map(link, attr); |
| goto out_put_link; |
| } |
| |
| new_prog = bpf_prog_get(attr->link_update.new_prog_fd); |
| if (IS_ERR(new_prog)) { |
| ret = PTR_ERR(new_prog); |
| goto out_put_link; |
| } |
| |
| if (flags & BPF_F_REPLACE) { |
| old_prog = bpf_prog_get(attr->link_update.old_prog_fd); |
| if (IS_ERR(old_prog)) { |
| ret = PTR_ERR(old_prog); |
| old_prog = NULL; |
| goto out_put_progs; |
| } |
| } else if (attr->link_update.old_prog_fd) { |
| ret = -EINVAL; |
| goto out_put_progs; |
| } |
| |
| if (link->ops->update_prog) |
| ret = link->ops->update_prog(link, new_prog, old_prog); |
| else |
| ret = -EINVAL; |
| |
| out_put_progs: |
| if (old_prog) |
| bpf_prog_put(old_prog); |
| if (ret) |
| bpf_prog_put(new_prog); |
| out_put_link: |
| bpf_link_put_direct(link); |
| return ret; |
| } |
| |
| #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd |
| |
| static int link_detach(union bpf_attr *attr) |
| { |
| struct bpf_link *link; |
| int ret; |
| |
| if (CHECK_ATTR(BPF_LINK_DETACH)) |
| return -EINVAL; |
| |
| link = bpf_link_get_from_fd(attr->link_detach.link_fd); |
| if (IS_ERR(link)) |
| return PTR_ERR(link); |
| |
| if (link->ops->detach) |
| ret = link->ops->detach(link); |
| else |
| ret = -EOPNOTSUPP; |
| |
| bpf_link_put_direct(link); |
| return ret; |
| } |
| |
| struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link) |
| { |
| return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT); |
| } |
| EXPORT_SYMBOL(bpf_link_inc_not_zero); |
| |
| struct bpf_link *bpf_link_by_id(u32 id) |
| { |
| struct bpf_link *link; |
| |
| if (!id) |
| return ERR_PTR(-ENOENT); |
| |
| spin_lock_bh(&link_idr_lock); |
| /* before link is "settled", ID is 0, pretend it doesn't exist yet */ |
| link = idr_find(&link_idr, id); |
| if (link) { |
| if (link->id) |
| link = bpf_link_inc_not_zero(link); |
| else |
| link = ERR_PTR(-EAGAIN); |
| } else { |
| link = ERR_PTR(-ENOENT); |
| } |
| spin_unlock_bh(&link_idr_lock); |
| return link; |
| } |
| |
| struct bpf_link *bpf_link_get_curr_or_next(u32 *id) |
| { |
| struct bpf_link *link; |
| |
| spin_lock_bh(&link_idr_lock); |
| again: |
| link = idr_get_next(&link_idr, id); |
| if (link) { |
| link = bpf_link_inc_not_zero(link); |
| if (IS_ERR(link)) { |
| (*id)++; |
| goto again; |
| } |
| } |
| spin_unlock_bh(&link_idr_lock); |
| |
| return link; |
| } |
| |
| #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id |
| |
| static int bpf_link_get_fd_by_id(const union bpf_attr *attr) |
| { |
| struct bpf_link *link; |
| u32 id = attr->link_id; |
| int fd; |
| |
| if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID)) |
| return -EINVAL; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| link = bpf_link_by_id(id); |
| if (IS_ERR(link)) |
| return PTR_ERR(link); |
| |
| fd = bpf_link_new_fd(link); |
| if (fd < 0) |
| bpf_link_put_direct(link); |
| |
| return fd; |
| } |
| |
| DEFINE_MUTEX(bpf_stats_enabled_mutex); |
| |
| static int bpf_stats_release(struct inode *inode, struct file *file) |
| { |
| mutex_lock(&bpf_stats_enabled_mutex); |
| static_key_slow_dec(&bpf_stats_enabled_key.key); |
| mutex_unlock(&bpf_stats_enabled_mutex); |
| return 0; |
| } |
| |
| static const struct file_operations bpf_stats_fops = { |
| .release = bpf_stats_release, |
| }; |
| |
| static int bpf_enable_runtime_stats(void) |
| { |
| int fd; |
| |
| mutex_lock(&bpf_stats_enabled_mutex); |
| |
| /* Set a very high limit to avoid overflow */ |
| if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) { |
| mutex_unlock(&bpf_stats_enabled_mutex); |
| return -EBUSY; |
| } |
| |
| fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC); |
| if (fd >= 0) |
| static_key_slow_inc(&bpf_stats_enabled_key.key); |
| |
| mutex_unlock(&bpf_stats_enabled_mutex); |
| return fd; |
| } |
| |
| #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type |
| |
| static int bpf_enable_stats(union bpf_attr *attr) |
| { |
| |
| if (CHECK_ATTR(BPF_ENABLE_STATS)) |
| return -EINVAL; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| switch (attr->enable_stats.type) { |
| case BPF_STATS_RUN_TIME: |
| return bpf_enable_runtime_stats(); |
| default: |
| break; |
| } |
| return -EINVAL; |
| } |
| |
| #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags |
| |
| static int bpf_iter_create(union bpf_attr *attr) |
| { |
| struct bpf_link *link; |
| int err; |
| |
| if (CHECK_ATTR(BPF_ITER_CREATE)) |
| return -EINVAL; |
| |
| if (attr->iter_create.flags) |
| return -EINVAL; |
| |
| link = bpf_link_get_from_fd(attr->iter_create.link_fd); |
| if (IS_ERR(link)) |
| return PTR_ERR(link); |
| |
| err = bpf_iter_new_fd(link); |
| bpf_link_put_direct(link); |
| |
| return err; |
| } |
| |
| #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags |
| |
| static int bpf_prog_bind_map(union bpf_attr *attr) |
| { |
| struct bpf_prog *prog; |
| struct bpf_map *map; |
| struct bpf_map **used_maps_old, **used_maps_new; |
| int i, ret = 0; |
| |
| if (CHECK_ATTR(BPF_PROG_BIND_MAP)) |
| return -EINVAL; |
| |
| if (attr->prog_bind_map.flags) |
| return -EINVAL; |
| |
| prog = bpf_prog_get(attr->prog_bind_map.prog_fd); |
| if (IS_ERR(prog)) |
| return PTR_ERR(prog); |
| |
| map = bpf_map_get(attr->prog_bind_map.map_fd); |
| if (IS_ERR(map)) { |
| ret = PTR_ERR(map); |
| goto out_prog_put; |
| } |
| |
| mutex_lock(&prog->aux->used_maps_mutex); |
| |
| used_maps_old = prog->aux->used_maps; |
| |
| for (i = 0; i < prog->aux->used_map_cnt; i++) |
| if (used_maps_old[i] == map) { |
| bpf_map_put(map); |
| goto out_unlock; |
| } |
| |
| used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1, |
| sizeof(used_maps_new[0]), |
| GFP_KERNEL); |
| if (!used_maps_new) { |
| ret = -ENOMEM; |
| goto out_unlock; |
| } |
| |
| /* The bpf program will not access the bpf map, but for the sake of |
| * simplicity, increase sleepable_refcnt for sleepable program as well. |
| */ |
| if (prog->sleepable) |
| atomic64_inc(&map->sleepable_refcnt); |
| memcpy(used_maps_new, used_maps_old, |
| sizeof(used_maps_old[0]) * prog->aux->used_map_cnt); |
| used_maps_new[prog->aux->used_map_cnt] = map; |
| |
| prog->aux->used_map_cnt++; |
| prog->aux->used_maps = used_maps_new; |
| |
| kfree(used_maps_old); |
| |
| out_unlock: |
| mutex_unlock(&prog->aux->used_maps_mutex); |
| |
| if (ret) |
| bpf_map_put(map); |
| out_prog_put: |
| bpf_prog_put(prog); |
| return ret; |
| } |
| |
| #define BPF_TOKEN_CREATE_LAST_FIELD token_create.bpffs_fd |
| |
| static int token_create(union bpf_attr *attr) |
| { |
| if (CHECK_ATTR(BPF_TOKEN_CREATE)) |
| return -EINVAL; |
| |
| /* no flags are supported yet */ |
| if (attr->token_create.flags) |
| return -EINVAL; |
| |
| return bpf_token_create(attr); |
| } |
| |
| static int __sys_bpf(enum bpf_cmd cmd, bpfptr_t uattr, unsigned int size) |
| { |
| union bpf_attr attr; |
| int err; |
| |
| err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); |
| if (err) |
| return err; |
| size = min_t(u32, size, sizeof(attr)); |
| |
| /* copy attributes from user space, may be less than sizeof(bpf_attr) */ |
| memset(&attr, 0, sizeof(attr)); |
| if (copy_from_bpfptr(&attr, uattr, size) != 0) |
| return -EFAULT; |
| |
| err = security_bpf(cmd, &attr, size); |
| if (err < 0) |
| return err; |
| |
| switch (cmd) { |
| case BPF_MAP_CREATE: |
| err = map_create(&attr); |
| break; |
| case BPF_MAP_LOOKUP_ELEM: |
| err = map_lookup_elem(&attr); |
| break; |
| case BPF_MAP_UPDATE_ELEM: |
| err = map_update_elem(&attr, uattr); |
| break; |
| case BPF_MAP_DELETE_ELEM: |
| err = map_delete_elem(&attr, uattr); |
| break; |
| case BPF_MAP_GET_NEXT_KEY: |
| err = map_get_next_key(&attr); |
| break; |
| case BPF_MAP_FREEZE: |
| err = map_freeze(&attr); |
| break; |
| case BPF_PROG_LOAD: |
| err = bpf_prog_load(&attr, uattr, size); |
| break; |
| case BPF_OBJ_PIN: |
| err = bpf_obj_pin(&attr); |
| break; |
| case BPF_OBJ_GET: |
| err = bpf_obj_get(&attr); |
| break; |
| case BPF_PROG_ATTACH: |
| err = bpf_prog_attach(&attr); |
| break; |
| case BPF_PROG_DETACH: |
| err = bpf_prog_detach(&attr); |
| break; |
| case BPF_PROG_QUERY: |
| err = bpf_prog_query(&attr, uattr.user); |
| break; |
| case BPF_PROG_TEST_RUN: |
| err = bpf_prog_test_run(&attr, uattr.user); |
| break; |
| case BPF_PROG_GET_NEXT_ID: |
| err = bpf_obj_get_next_id(&attr, uattr.user, |
| &prog_idr, &prog_idr_lock); |
| break; |
| case BPF_MAP_GET_NEXT_ID: |
| err = bpf_obj_get_next_id(&attr, uattr.user, |
| &map_idr, &map_idr_lock); |
| break; |
| case BPF_BTF_GET_NEXT_ID: |
| err = bpf_obj_get_next_id(&attr, uattr.user, |
| &btf_idr, &btf_idr_lock); |
| break; |
| case BPF_PROG_GET_FD_BY_ID: |
| err = bpf_prog_get_fd_by_id(&attr); |
| break; |
| case BPF_MAP_GET_FD_BY_ID: |
| err = bpf_map_get_fd_by_id(&attr); |
| break; |
| case BPF_OBJ_GET_INFO_BY_FD: |
| err = bpf_obj_get_info_by_fd(&attr, uattr.user); |
| break; |
| case BPF_RAW_TRACEPOINT_OPEN: |
| err = bpf_raw_tracepoint_open(&attr); |
| break; |
| case BPF_BTF_LOAD: |
| err = bpf_btf_load(&attr, uattr, size); |
| break; |
| case BPF_BTF_GET_FD_BY_ID: |
| err = bpf_btf_get_fd_by_id(&attr); |
| break; |
| case BPF_TASK_FD_QUERY: |
| err = bpf_task_fd_query(&attr, uattr.user); |
| break; |
| case BPF_MAP_LOOKUP_AND_DELETE_ELEM: |
| err = map_lookup_and_delete_elem(&attr); |
| break; |
| case BPF_MAP_LOOKUP_BATCH: |
| err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH); |
| break; |
| case BPF_MAP_LOOKUP_AND_DELETE_BATCH: |
| err = bpf_map_do_batch(&attr, uattr.user, |
| BPF_MAP_LOOKUP_AND_DELETE_BATCH); |
| break; |
| case BPF_MAP_UPDATE_BATCH: |
| err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH); |
| break; |
| case BPF_MAP_DELETE_BATCH: |
| err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH); |
| break; |
| case BPF_LINK_CREATE: |
| err = link_create(&attr, uattr); |
| break; |
| case BPF_LINK_UPDATE: |
| err = link_update(&attr); |
| break; |
| case BPF_LINK_GET_FD_BY_ID: |
| err = bpf_link_get_fd_by_id(&attr); |
| break; |
| case BPF_LINK_GET_NEXT_ID: |
| err = bpf_obj_get_next_id(&attr, uattr.user, |
| &link_idr, &link_idr_lock); |
| break; |
| case BPF_ENABLE_STATS: |
| err = bpf_enable_stats(&attr); |
| break; |
| case BPF_ITER_CREATE: |
| err = bpf_iter_create(&attr); |
| break; |
| case BPF_LINK_DETACH: |
| err = link_detach(&attr); |
| break; |
| case BPF_PROG_BIND_MAP: |
| err = bpf_prog_bind_map(&attr); |
| break; |
| case BPF_TOKEN_CREATE: |
| err = token_create(&attr); |
| break; |
| default: |
| err = -EINVAL; |
| break; |
| } |
| |
| return err; |
| } |
| |
| SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) |
| { |
| return __sys_bpf(cmd, USER_BPFPTR(uattr), size); |
| } |
| |
| static bool syscall_prog_is_valid_access(int off, int size, |
| enum bpf_access_type type, |
| const struct bpf_prog *prog, |
| struct bpf_insn_access_aux *info) |
| { |
| if (off < 0 || off >= U16_MAX) |
| return false; |
| if (off % size != 0) |
| return false; |
| return true; |
| } |
| |
| BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size) |
| { |
| switch (cmd) { |
| case BPF_MAP_CREATE: |
| case BPF_MAP_DELETE_ELEM: |
| case BPF_MAP_UPDATE_ELEM: |
| case BPF_MAP_FREEZE: |
| case BPF_MAP_GET_FD_BY_ID: |
| case BPF_PROG_LOAD: |
| case BPF_BTF_LOAD: |
| case BPF_LINK_CREATE: |
| case BPF_RAW_TRACEPOINT_OPEN: |
| break; |
| default: |
| return -EINVAL; |
| } |
| return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size); |
| } |
| |
| |
| /* To shut up -Wmissing-prototypes. |
| * This function is used by the kernel light skeleton |
| * to load bpf programs when modules are loaded or during kernel boot. |
| * See tools/lib/bpf/skel_internal.h |
| */ |
| int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size); |
| |
| int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size) |
| { |
| struct bpf_prog * __maybe_unused prog; |
| struct bpf_tramp_run_ctx __maybe_unused run_ctx; |
| |
| switch (cmd) { |
| #ifdef CONFIG_BPF_JIT /* __bpf_prog_enter_sleepable used by trampoline and JIT */ |
| case BPF_PROG_TEST_RUN: |
| if (attr->test.data_in || attr->test.data_out || |
| attr->test.ctx_out || attr->test.duration || |
| attr->test.repeat || attr->test.flags) |
| return -EINVAL; |
| |
| prog = bpf_prog_get_type(attr->test.prog_fd, BPF_PROG_TYPE_SYSCALL); |
| if (IS_ERR(prog)) |
| return PTR_ERR(prog); |
| |
| if (attr->test.ctx_size_in < prog->aux->max_ctx_offset || |
| attr->test.ctx_size_in > U16_MAX) { |
| bpf_prog_put(prog); |
| return -EINVAL; |
| } |
| |
| run_ctx.bpf_cookie = 0; |
| if (!__bpf_prog_enter_sleepable_recur(prog, &run_ctx)) { |
| /* recursion detected */ |
| __bpf_prog_exit_sleepable_recur(prog, 0, &run_ctx); |
| bpf_prog_put(prog); |
| return -EBUSY; |
| } |
| attr->test.retval = bpf_prog_run(prog, (void *) (long) attr->test.ctx_in); |
| __bpf_prog_exit_sleepable_recur(prog, 0 /* bpf_prog_run does runtime stats */, |
| &run_ctx); |
| bpf_prog_put(prog); |
| return 0; |
| #endif |
| default: |
| return ____bpf_sys_bpf(cmd, attr, size); |
| } |
| } |
| EXPORT_SYMBOL(kern_sys_bpf); |
| |
| static const struct bpf_func_proto bpf_sys_bpf_proto = { |
| .func = bpf_sys_bpf, |
| .gpl_only = false, |
| .ret_type = RET_INTEGER, |
| .arg1_type = ARG_ANYTHING, |
| .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY, |
| .arg3_type = ARG_CONST_SIZE, |
| }; |
| |
| const struct bpf_func_proto * __weak |
| tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) |
| { |
| return bpf_base_func_proto(func_id, prog); |
| } |
| |
| BPF_CALL_1(bpf_sys_close, u32, fd) |
| { |
| /* When bpf program calls this helper there should not be |
| * an fdget() without matching completed fdput(). |
| * This helper is allowed in the following callchain only: |
| * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close |
| */ |
| return close_fd(fd); |
| } |
| |
| static const struct bpf_func_proto bpf_sys_close_proto = { |
| .func = bpf_sys_close, |
| .gpl_only = false, |
| .ret_type = RET_INTEGER, |
| .arg1_type = ARG_ANYTHING, |
| }; |
| |
| BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res) |
| { |
| *res = 0; |
| if (flags) |
| return -EINVAL; |
| |
| if (name_sz <= 1 || name[name_sz - 1]) |
| return -EINVAL; |
| |
| if (!bpf_dump_raw_ok(current_cred())) |
| return -EPERM; |
| |
| *res = kallsyms_lookup_name(name); |
| return *res ? 0 : -ENOENT; |
| } |
| |
| static const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = { |
| .func = bpf_kallsyms_lookup_name, |
| .gpl_only = false, |
| .ret_type = RET_INTEGER, |
| .arg1_type = ARG_PTR_TO_MEM, |
| .arg2_type = ARG_CONST_SIZE_OR_ZERO, |
| .arg3_type = ARG_ANYTHING, |
| .arg4_type = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_UNINIT | MEM_ALIGNED, |
| .arg4_size = sizeof(u64), |
| }; |
| |
| static const struct bpf_func_proto * |
| syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) |
| { |
| switch (func_id) { |
| case BPF_FUNC_sys_bpf: |
| return !bpf_token_capable(prog->aux->token, CAP_PERFMON) |
| ? NULL : &bpf_sys_bpf_proto; |
| case BPF_FUNC_btf_find_by_name_kind: |
| return &bpf_btf_find_by_name_kind_proto; |
| case BPF_FUNC_sys_close: |
| return &bpf_sys_close_proto; |
| case BPF_FUNC_kallsyms_lookup_name: |
| return &bpf_kallsyms_lookup_name_proto; |
| default: |
| return tracing_prog_func_proto(func_id, prog); |
| } |
| } |
| |
| const struct bpf_verifier_ops bpf_syscall_verifier_ops = { |
| .get_func_proto = syscall_prog_func_proto, |
| .is_valid_access = syscall_prog_is_valid_access, |
| }; |
| |
| const struct bpf_prog_ops bpf_syscall_prog_ops = { |
| .test_run = bpf_prog_test_run_syscall, |
| }; |
| |
| #ifdef CONFIG_SYSCTL |
| static int bpf_stats_handler(const struct ctl_table *table, int write, |
| void *buffer, size_t *lenp, loff_t *ppos) |
| { |
| struct static_key *key = (struct static_key *)table->data; |
| static int saved_val; |
| int val, ret; |
| struct ctl_table tmp = { |
| .data = &val, |
| .maxlen = sizeof(val), |
| .mode = table->mode, |
| .extra1 = SYSCTL_ZERO, |
| .extra2 = SYSCTL_ONE, |
| }; |
| |
| if (write && !capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| mutex_lock(&bpf_stats_enabled_mutex); |
| val = saved_val; |
| ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); |
| if (write && !ret && val != saved_val) { |
| if (val) |
| static_key_slow_inc(key); |
| else |
| static_key_slow_dec(key); |
| saved_val = val; |
| } |
| mutex_unlock(&bpf_stats_enabled_mutex); |
| return ret; |
| } |
| |
| void __weak unpriv_ebpf_notify(int new_state) |
| { |
| } |
| |
| static int bpf_unpriv_handler(const struct ctl_table *table, int write, |
| void *buffer, size_t *lenp, loff_t *ppos) |
| { |
| int ret, unpriv_enable = *(int *)table->data; |
| bool locked_state = unpriv_enable == 1; |
| struct ctl_table tmp = *table; |
| |
| if (write && !capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| tmp.data = &unpriv_enable; |
| ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); |
| if (write && !ret) { |
| if (locked_state && unpriv_enable != 1) |
| return -EPERM; |
| *(int *)table->data = unpriv_enable; |
| } |
| |
| if (write) |
| unpriv_ebpf_notify(unpriv_enable); |
| |
| return ret; |
| } |
| |
| static struct ctl_table bpf_syscall_table[] = { |
| { |
| .procname = "unprivileged_bpf_disabled", |
| .data = &sysctl_unprivileged_bpf_disabled, |
| .maxlen = sizeof(sysctl_unprivileged_bpf_disabled), |
| .mode = 0644, |
| .proc_handler = bpf_unpriv_handler, |
| .extra1 = SYSCTL_ZERO, |
| .extra2 = SYSCTL_TWO, |
| }, |
| { |
| .procname = "bpf_stats_enabled", |
| .data = &bpf_stats_enabled_key.key, |
| .mode = 0644, |
| .proc_handler = bpf_stats_handler, |
| }, |
| }; |
| |
| static int __init bpf_syscall_sysctl_init(void) |
| { |
| register_sysctl_init("kernel", bpf_syscall_table); |
| return 0; |
| } |
| late_initcall(bpf_syscall_sysctl_init); |
| #endif /* CONFIG_SYSCTL */ |