bpf: Eliminate rlimit-based memory accounting for bpf progs
Do not use rlimit-based memory accounting for bpf progs. It has been
replaced with memcg-based memory accounting.
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201201215900.3569844-34-guro@fb.com
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 29096d9..d16dd49 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1632,51 +1632,6 @@ static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op)
audit_log_end(ab);
}
-int __bpf_prog_charge(struct user_struct *user, u32 pages)
-{
- unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
- unsigned long user_bufs;
-
- if (user) {
- user_bufs = atomic_long_add_return(pages, &user->locked_vm);
- if (user_bufs > memlock_limit) {
- atomic_long_sub(pages, &user->locked_vm);
- return -EPERM;
- }
- }
-
- return 0;
-}
-
-void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
-{
- if (user)
- atomic_long_sub(pages, &user->locked_vm);
-}
-
-static int bpf_prog_charge_memlock(struct bpf_prog *prog)
-{
- struct user_struct *user = get_current_user();
- int ret;
-
- ret = __bpf_prog_charge(user, prog->pages);
- if (ret) {
- free_uid(user);
- return ret;
- }
-
- prog->aux->user = user;
- return 0;
-}
-
-static void bpf_prog_uncharge_memlock(struct bpf_prog *prog)
-{
- struct user_struct *user = prog->aux->user;
-
- __bpf_prog_uncharge(user, prog->pages);
- free_uid(user);
-}
-
static int bpf_prog_alloc_id(struct bpf_prog *prog)
{
int id;
@@ -1726,7 +1681,7 @@ static void __bpf_prog_put_rcu(struct rcu_head *rcu)
kvfree(aux->func_info);
kfree(aux->func_info_aux);
- bpf_prog_uncharge_memlock(aux->prog);
+ free_uid(aux->user);
security_bpf_prog_free(aux);
bpf_prog_free(aux->prog);
}
@@ -2164,7 +2119,7 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
dst_prog = bpf_prog_get(attr->attach_prog_fd);
if (IS_ERR(dst_prog)) {
err = PTR_ERR(dst_prog);
- goto free_prog_nouncharge;
+ goto free_prog;
}
prog->aux->dst_prog = dst_prog;
}
@@ -2174,18 +2129,15 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
err = security_bpf_prog_alloc(prog->aux);
if (err)
- goto free_prog_nouncharge;
+ goto free_prog;
- err = bpf_prog_charge_memlock(prog);
- if (err)
- goto free_prog_sec;
-
+ prog->aux->user = get_current_user();
prog->len = attr->insn_cnt;
err = -EFAULT;
if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns),
bpf_prog_insn_size(prog)) != 0)
- goto free_prog;
+ goto free_prog_sec;
prog->orig_prog = NULL;
prog->jited = 0;
@@ -2196,19 +2148,19 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
if (bpf_prog_is_dev_bound(prog->aux)) {
err = bpf_prog_offload_init(prog, attr);
if (err)
- goto free_prog;
+ goto free_prog_sec;
}
/* find program type: socket_filter vs tracing_filter */
err = find_prog_type(type, prog);
if (err < 0)
- goto free_prog;
+ goto free_prog_sec;
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;
+ goto free_prog_sec;
/* run eBPF verifier */
err = bpf_check(&prog, attr, uattr);
@@ -2253,11 +2205,10 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
*/
__bpf_prog_put_noref(prog, prog->aux->func_cnt);
return err;
-free_prog:
- bpf_prog_uncharge_memlock(prog);
free_prog_sec:
+ free_uid(prog->aux->user);
security_bpf_prog_free(prog->aux);
-free_prog_nouncharge:
+free_prog:
bpf_prog_free(prog);
return err;
}
