| // SPDX-License-Identifier: GPL-2.0 |
| /* -*- linux-c -*- |
| * sysctl_net_core.c: sysctl interface to net core subsystem. |
| * |
| * Begun April 1, 1996, Mike Shaver. |
| * Added /proc/sys/net/core directory entry (empty =) ). [MS] |
| */ |
| |
| #include <linux/mm.h> |
| #include <linux/sysctl.h> |
| #include <linux/module.h> |
| #include <linux/socket.h> |
| #include <linux/netdevice.h> |
| #include <linux/ratelimit.h> |
| #include <linux/vmalloc.h> |
| #include <linux/init.h> |
| #include <linux/slab.h> |
| |
| #include <net/ip.h> |
| #include <net/sock.h> |
| #include <net/net_ratelimit.h> |
| #include <net/busy_poll.h> |
| #include <net/pkt_sched.h> |
| |
| static int two __maybe_unused = 2; |
| static int three = 3; |
| static int min_sndbuf = SOCK_MIN_SNDBUF; |
| static int min_rcvbuf = SOCK_MIN_RCVBUF; |
| static int max_skb_frags = MAX_SKB_FRAGS; |
| static long long_one __maybe_unused = 1; |
| static long long_max __maybe_unused = LONG_MAX; |
| |
| static int net_msg_warn; /* Unused, but still a sysctl */ |
| |
| int sysctl_fb_tunnels_only_for_init_net __read_mostly = 0; |
| EXPORT_SYMBOL(sysctl_fb_tunnels_only_for_init_net); |
| |
| /* 0 - Keep current behavior: |
| * IPv4: inherit all current settings from init_net |
| * IPv6: reset all settings to default |
| * 1 - Both inherit all current settings from init_net |
| * 2 - Both reset all settings to default |
| * 3 - Both inherit all settings from current netns |
| */ |
| int sysctl_devconf_inherit_init_net __read_mostly; |
| EXPORT_SYMBOL(sysctl_devconf_inherit_init_net); |
| |
| #ifdef CONFIG_RPS |
| static int rps_sock_flow_sysctl(struct ctl_table *table, int write, |
| void *buffer, size_t *lenp, loff_t *ppos) |
| { |
| unsigned int orig_size, size; |
| int ret, i; |
| struct ctl_table tmp = { |
| .data = &size, |
| .maxlen = sizeof(size), |
| .mode = table->mode |
| }; |
| struct rps_sock_flow_table *orig_sock_table, *sock_table; |
| static DEFINE_MUTEX(sock_flow_mutex); |
| |
| mutex_lock(&sock_flow_mutex); |
| |
| orig_sock_table = rcu_dereference_protected(rps_sock_flow_table, |
| lockdep_is_held(&sock_flow_mutex)); |
| size = orig_size = orig_sock_table ? orig_sock_table->mask + 1 : 0; |
| |
| ret = proc_dointvec(&tmp, write, buffer, lenp, ppos); |
| |
| if (write) { |
| if (size) { |
| if (size > 1<<29) { |
| /* Enforce limit to prevent overflow */ |
| mutex_unlock(&sock_flow_mutex); |
| return -EINVAL; |
| } |
| size = roundup_pow_of_two(size); |
| if (size != orig_size) { |
| sock_table = |
| vmalloc(RPS_SOCK_FLOW_TABLE_SIZE(size)); |
| if (!sock_table) { |
| mutex_unlock(&sock_flow_mutex); |
| return -ENOMEM; |
| } |
| rps_cpu_mask = roundup_pow_of_two(nr_cpu_ids) - 1; |
| sock_table->mask = size - 1; |
| } else |
| sock_table = orig_sock_table; |
| |
| for (i = 0; i < size; i++) |
| sock_table->ents[i] = RPS_NO_CPU; |
| } else |
| sock_table = NULL; |
| |
| if (sock_table != orig_sock_table) { |
| rcu_assign_pointer(rps_sock_flow_table, sock_table); |
| if (sock_table) { |
| static_branch_inc(&rps_needed); |
| static_branch_inc(&rfs_needed); |
| } |
| if (orig_sock_table) { |
| static_branch_dec(&rps_needed); |
| static_branch_dec(&rfs_needed); |
| synchronize_rcu(); |
| vfree(orig_sock_table); |
| } |
| } |
| } |
| |
| mutex_unlock(&sock_flow_mutex); |
| |
| return ret; |
| } |
| #endif /* CONFIG_RPS */ |
| |
| #ifdef CONFIG_NET_FLOW_LIMIT |
| static DEFINE_MUTEX(flow_limit_update_mutex); |
| |
| static int flow_limit_cpu_sysctl(struct ctl_table *table, int write, |
| void *buffer, size_t *lenp, loff_t *ppos) |
| { |
| struct sd_flow_limit *cur; |
| struct softnet_data *sd; |
| cpumask_var_t mask; |
| int i, len, ret = 0; |
| |
| if (!alloc_cpumask_var(&mask, GFP_KERNEL)) |
| return -ENOMEM; |
| |
| if (write) { |
| ret = cpumask_parse(buffer, mask); |
| if (ret) |
| goto done; |
| |
| mutex_lock(&flow_limit_update_mutex); |
| len = sizeof(*cur) + netdev_flow_limit_table_len; |
| for_each_possible_cpu(i) { |
| sd = &per_cpu(softnet_data, i); |
| cur = rcu_dereference_protected(sd->flow_limit, |
| lockdep_is_held(&flow_limit_update_mutex)); |
| if (cur && !cpumask_test_cpu(i, mask)) { |
| RCU_INIT_POINTER(sd->flow_limit, NULL); |
| synchronize_rcu(); |
| kfree(cur); |
| } else if (!cur && cpumask_test_cpu(i, mask)) { |
| cur = kzalloc_node(len, GFP_KERNEL, |
| cpu_to_node(i)); |
| if (!cur) { |
| /* not unwinding previous changes */ |
| ret = -ENOMEM; |
| goto write_unlock; |
| } |
| cur->num_buckets = netdev_flow_limit_table_len; |
| rcu_assign_pointer(sd->flow_limit, cur); |
| } |
| } |
| write_unlock: |
| mutex_unlock(&flow_limit_update_mutex); |
| } else { |
| char kbuf[128]; |
| |
| if (*ppos || !*lenp) { |
| *lenp = 0; |
| goto done; |
| } |
| |
| cpumask_clear(mask); |
| rcu_read_lock(); |
| for_each_possible_cpu(i) { |
| sd = &per_cpu(softnet_data, i); |
| if (rcu_dereference(sd->flow_limit)) |
| cpumask_set_cpu(i, mask); |
| } |
| rcu_read_unlock(); |
| |
| len = min(sizeof(kbuf) - 1, *lenp); |
| len = scnprintf(kbuf, len, "%*pb", cpumask_pr_args(mask)); |
| if (!len) { |
| *lenp = 0; |
| goto done; |
| } |
| if (len < *lenp) |
| kbuf[len++] = '\n'; |
| memcpy(buffer, kbuf, len); |
| *lenp = len; |
| *ppos += len; |
| } |
| |
| done: |
| free_cpumask_var(mask); |
| return ret; |
| } |
| |
| static int flow_limit_table_len_sysctl(struct ctl_table *table, int write, |
| void *buffer, size_t *lenp, loff_t *ppos) |
| { |
| unsigned int old, *ptr; |
| int ret; |
| |
| mutex_lock(&flow_limit_update_mutex); |
| |
| ptr = table->data; |
| old = *ptr; |
| ret = proc_dointvec(table, write, buffer, lenp, ppos); |
| if (!ret && write && !is_power_of_2(*ptr)) { |
| *ptr = old; |
| ret = -EINVAL; |
| } |
| |
| mutex_unlock(&flow_limit_update_mutex); |
| return ret; |
| } |
| #endif /* CONFIG_NET_FLOW_LIMIT */ |
| |
| #ifdef CONFIG_NET_SCHED |
| static int set_default_qdisc(struct ctl_table *table, int write, |
| void *buffer, size_t *lenp, loff_t *ppos) |
| { |
| char id[IFNAMSIZ]; |
| struct ctl_table tbl = { |
| .data = id, |
| .maxlen = IFNAMSIZ, |
| }; |
| int ret; |
| |
| qdisc_get_default(id, IFNAMSIZ); |
| |
| ret = proc_dostring(&tbl, write, buffer, lenp, ppos); |
| if (write && ret == 0) |
| ret = qdisc_set_default(id); |
| return ret; |
| } |
| #endif |
| |
| static int proc_do_dev_weight(struct ctl_table *table, int write, |
| void *buffer, size_t *lenp, loff_t *ppos) |
| { |
| int ret; |
| |
| ret = proc_dointvec(table, write, buffer, lenp, ppos); |
| if (ret != 0) |
| return ret; |
| |
| dev_rx_weight = weight_p * dev_weight_rx_bias; |
| dev_tx_weight = weight_p * dev_weight_tx_bias; |
| |
| return ret; |
| } |
| |
| static int proc_do_rss_key(struct ctl_table *table, int write, |
| void *buffer, size_t *lenp, loff_t *ppos) |
| { |
| struct ctl_table fake_table; |
| char buf[NETDEV_RSS_KEY_LEN * 3]; |
| |
| snprintf(buf, sizeof(buf), "%*phC", NETDEV_RSS_KEY_LEN, netdev_rss_key); |
| fake_table.data = buf; |
| fake_table.maxlen = sizeof(buf); |
| return proc_dostring(&fake_table, write, buffer, lenp, ppos); |
| } |
| |
| #ifdef CONFIG_BPF_JIT |
| static int proc_dointvec_minmax_bpf_enable(struct ctl_table *table, int write, |
| void *buffer, size_t *lenp, |
| loff_t *ppos) |
| { |
| int ret, jit_enable = *(int *)table->data; |
| struct ctl_table tmp = *table; |
| |
| if (write && !capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| tmp.data = &jit_enable; |
| ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); |
| if (write && !ret) { |
| if (jit_enable < 2 || |
| (jit_enable == 2 && bpf_dump_raw_ok(current_cred()))) { |
| *(int *)table->data = jit_enable; |
| if (jit_enable == 2) |
| pr_warn("bpf_jit_enable = 2 was set! NEVER use this in production, only for JIT debugging!\n"); |
| } else { |
| ret = -EPERM; |
| } |
| } |
| return ret; |
| } |
| |
| # ifdef CONFIG_HAVE_EBPF_JIT |
| static int |
| proc_dointvec_minmax_bpf_restricted(struct ctl_table *table, int write, |
| void *buffer, size_t *lenp, loff_t *ppos) |
| { |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| return proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
| } |
| # endif /* CONFIG_HAVE_EBPF_JIT */ |
| |
| static int |
| proc_dolongvec_minmax_bpf_restricted(struct ctl_table *table, int write, |
| void *buffer, size_t *lenp, loff_t *ppos) |
| { |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| return proc_doulongvec_minmax(table, write, buffer, lenp, ppos); |
| } |
| #endif |
| |
| static struct ctl_table net_core_table[] = { |
| #ifdef CONFIG_NET |
| { |
| .procname = "wmem_max", |
| .data = &sysctl_wmem_max, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec_minmax, |
| .extra1 = &min_sndbuf, |
| }, |
| { |
| .procname = "rmem_max", |
| .data = &sysctl_rmem_max, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec_minmax, |
| .extra1 = &min_rcvbuf, |
| }, |
| { |
| .procname = "wmem_default", |
| .data = &sysctl_wmem_default, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec_minmax, |
| .extra1 = &min_sndbuf, |
| }, |
| { |
| .procname = "rmem_default", |
| .data = &sysctl_rmem_default, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec_minmax, |
| .extra1 = &min_rcvbuf, |
| }, |
| { |
| .procname = "dev_weight", |
| .data = &weight_p, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_do_dev_weight, |
| }, |
| { |
| .procname = "dev_weight_rx_bias", |
| .data = &dev_weight_rx_bias, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_do_dev_weight, |
| }, |
| { |
| .procname = "dev_weight_tx_bias", |
| .data = &dev_weight_tx_bias, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_do_dev_weight, |
| }, |
| { |
| .procname = "netdev_max_backlog", |
| .data = &netdev_max_backlog, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec |
| }, |
| { |
| .procname = "netdev_rss_key", |
| .data = &netdev_rss_key, |
| .maxlen = sizeof(int), |
| .mode = 0444, |
| .proc_handler = proc_do_rss_key, |
| }, |
| #ifdef CONFIG_BPF_JIT |
| { |
| .procname = "bpf_jit_enable", |
| .data = &bpf_jit_enable, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec_minmax_bpf_enable, |
| # ifdef CONFIG_BPF_JIT_ALWAYS_ON |
| .extra1 = SYSCTL_ONE, |
| .extra2 = SYSCTL_ONE, |
| # else |
| .extra1 = SYSCTL_ZERO, |
| .extra2 = &two, |
| # endif |
| }, |
| # ifdef CONFIG_HAVE_EBPF_JIT |
| { |
| .procname = "bpf_jit_harden", |
| .data = &bpf_jit_harden, |
| .maxlen = sizeof(int), |
| .mode = 0600, |
| .proc_handler = proc_dointvec_minmax_bpf_restricted, |
| .extra1 = SYSCTL_ZERO, |
| .extra2 = &two, |
| }, |
| { |
| .procname = "bpf_jit_kallsyms", |
| .data = &bpf_jit_kallsyms, |
| .maxlen = sizeof(int), |
| .mode = 0600, |
| .proc_handler = proc_dointvec_minmax_bpf_restricted, |
| .extra1 = SYSCTL_ZERO, |
| .extra2 = SYSCTL_ONE, |
| }, |
| # endif |
| { |
| .procname = "bpf_jit_limit", |
| .data = &bpf_jit_limit, |
| .maxlen = sizeof(long), |
| .mode = 0600, |
| .proc_handler = proc_dolongvec_minmax_bpf_restricted, |
| .extra1 = &long_one, |
| .extra2 = &long_max, |
| }, |
| #endif |
| { |
| .procname = "netdev_tstamp_prequeue", |
| .data = &netdev_tstamp_prequeue, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec |
| }, |
| { |
| .procname = "message_cost", |
| .data = &net_ratelimit_state.interval, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec_jiffies, |
| }, |
| { |
| .procname = "message_burst", |
| .data = &net_ratelimit_state.burst, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec, |
| }, |
| { |
| .procname = "optmem_max", |
| .data = &sysctl_optmem_max, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec |
| }, |
| { |
| .procname = "tstamp_allow_data", |
| .data = &sysctl_tstamp_allow_data, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec_minmax, |
| .extra1 = SYSCTL_ZERO, |
| .extra2 = SYSCTL_ONE |
| }, |
| #ifdef CONFIG_RPS |
| { |
| .procname = "rps_sock_flow_entries", |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = rps_sock_flow_sysctl |
| }, |
| #endif |
| #ifdef CONFIG_NET_FLOW_LIMIT |
| { |
| .procname = "flow_limit_cpu_bitmap", |
| .mode = 0644, |
| .proc_handler = flow_limit_cpu_sysctl |
| }, |
| { |
| .procname = "flow_limit_table_len", |
| .data = &netdev_flow_limit_table_len, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = flow_limit_table_len_sysctl |
| }, |
| #endif /* CONFIG_NET_FLOW_LIMIT */ |
| #ifdef CONFIG_NET_RX_BUSY_POLL |
| { |
| .procname = "busy_poll", |
| .data = &sysctl_net_busy_poll, |
| .maxlen = sizeof(unsigned int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec_minmax, |
| .extra1 = SYSCTL_ZERO, |
| }, |
| { |
| .procname = "busy_read", |
| .data = &sysctl_net_busy_read, |
| .maxlen = sizeof(unsigned int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec_minmax, |
| .extra1 = SYSCTL_ZERO, |
| }, |
| #endif |
| #ifdef CONFIG_NET_SCHED |
| { |
| .procname = "default_qdisc", |
| .mode = 0644, |
| .maxlen = IFNAMSIZ, |
| .proc_handler = set_default_qdisc |
| }, |
| #endif |
| #endif /* CONFIG_NET */ |
| { |
| .procname = "netdev_budget", |
| .data = &netdev_budget, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec |
| }, |
| { |
| .procname = "warnings", |
| .data = &net_msg_warn, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec |
| }, |
| { |
| .procname = "max_skb_frags", |
| .data = &sysctl_max_skb_frags, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec_minmax, |
| .extra1 = SYSCTL_ONE, |
| .extra2 = &max_skb_frags, |
| }, |
| { |
| .procname = "netdev_budget_usecs", |
| .data = &netdev_budget_usecs, |
| .maxlen = sizeof(unsigned int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec_minmax, |
| .extra1 = SYSCTL_ZERO, |
| }, |
| { |
| .procname = "fb_tunnels_only_for_init_net", |
| .data = &sysctl_fb_tunnels_only_for_init_net, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec_minmax, |
| .extra1 = SYSCTL_ZERO, |
| .extra2 = SYSCTL_ONE, |
| }, |
| { |
| .procname = "devconf_inherit_init_net", |
| .data = &sysctl_devconf_inherit_init_net, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec_minmax, |
| .extra1 = SYSCTL_ZERO, |
| .extra2 = &three, |
| }, |
| { |
| .procname = "high_order_alloc_disable", |
| .data = &net_high_order_alloc_disable_key.key, |
| .maxlen = sizeof(net_high_order_alloc_disable_key), |
| .mode = 0644, |
| .proc_handler = proc_do_static_key, |
| }, |
| { |
| .procname = "gro_normal_batch", |
| .data = &gro_normal_batch, |
| .maxlen = sizeof(unsigned int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec_minmax, |
| .extra1 = SYSCTL_ONE, |
| }, |
| { } |
| }; |
| |
| static struct ctl_table netns_core_table[] = { |
| { |
| .procname = "somaxconn", |
| .data = &init_net.core.sysctl_somaxconn, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .extra1 = SYSCTL_ZERO, |
| .proc_handler = proc_dointvec_minmax |
| }, |
| { } |
| }; |
| |
| static __net_init int sysctl_core_net_init(struct net *net) |
| { |
| struct ctl_table *tbl; |
| |
| tbl = netns_core_table; |
| if (!net_eq(net, &init_net)) { |
| tbl = kmemdup(tbl, sizeof(netns_core_table), GFP_KERNEL); |
| if (tbl == NULL) |
| goto err_dup; |
| |
| tbl[0].data = &net->core.sysctl_somaxconn; |
| |
| /* Don't export any sysctls to unprivileged users */ |
| if (net->user_ns != &init_user_ns) { |
| tbl[0].procname = NULL; |
| } |
| } |
| |
| net->core.sysctl_hdr = register_net_sysctl(net, "net/core", tbl); |
| if (net->core.sysctl_hdr == NULL) |
| goto err_reg; |
| |
| return 0; |
| |
| err_reg: |
| if (tbl != netns_core_table) |
| kfree(tbl); |
| err_dup: |
| return -ENOMEM; |
| } |
| |
| static __net_exit void sysctl_core_net_exit(struct net *net) |
| { |
| struct ctl_table *tbl; |
| |
| tbl = net->core.sysctl_hdr->ctl_table_arg; |
| unregister_net_sysctl_table(net->core.sysctl_hdr); |
| BUG_ON(tbl == netns_core_table); |
| kfree(tbl); |
| } |
| |
| static __net_initdata struct pernet_operations sysctl_core_ops = { |
| .init = sysctl_core_net_init, |
| .exit = sysctl_core_net_exit, |
| }; |
| |
| static __init int sysctl_core_init(void) |
| { |
| register_net_sysctl(&init_net, "net/core", net_core_table); |
| return register_pernet_subsys(&sysctl_core_ops); |
| } |
| |
| fs_initcall(sysctl_core_init); |