net/core/sysctl_net_core.c

   1 /* -*- linux-c -*-
   2  * sysctl_net_core.c: sysctl interface to net core subsystem.
   3  *
   4  * Begun April 1, 1996, Mike Shaver.
   5  * Added /proc/sys/net/core directory entry (empty =) ). [MS]
   6  */
   7
   8 #include <linux/mm.h>
   9 #include <linux/sysctl.h>
  10 #include <linux/module.h>
  11 #include <linux/socket.h>
  12 #include <linux/netdevice.h>
  13 #include <linux/ratelimit.h>
  14 #include <linux/vmalloc.h>
  15 #include <linux/init.h>
  16 #include <linux/slab.h>
  17
  18 #include <net/ip.h>
  19 #include <net/sock.h>
  20 #include <net/net_ratelimit.h>
  21
  22 #ifdef CONFIG_RPS
  23 static int rps_sock_flow_sysctl(ctl_table *table, int write,
  24                                 void __user *buffer, size_t *lenp, loff_t *ppos)
  25 {
  26         unsigned int orig_size, size;
  27         int ret, i;
  28         ctl_table tmp = {
  29                 .data = &size,
  30                 .maxlen = sizeof(size),
  31                 .mode = table->mode
  32         };
  33         struct rps_sock_flow_table *orig_sock_table, *sock_table;
  34         static DEFINE_MUTEX(sock_flow_mutex);
  35
  36         mutex_lock(&sock_flow_mutex);
  37
  38         orig_sock_table = rcu_dereference_protected(rps_sock_flow_table,
  39                                         lockdep_is_held(&sock_flow_mutex));
  40         size = orig_size = orig_sock_table ? orig_sock_table->mask + 1 : 0;
  41
  42         ret = proc_dointvec(&tmp, write, buffer, lenp, ppos);
  43
  44         if (write) {
  45                 if (size) {
  46                         if (size > 1<<30) {
  47                                 /* Enforce limit to prevent overflow */
  48                                 mutex_unlock(&sock_flow_mutex);
  49                                 return -EINVAL;
  50                         }
  51                         size = roundup_pow_of_two(size);
  52                         if (size != orig_size) {
  53                                 sock_table =
  54                                     vmalloc(RPS_SOCK_FLOW_TABLE_SIZE(size));
  55                                 if (!sock_table) {
  56                                         mutex_unlock(&sock_flow_mutex);
  57                                         return -ENOMEM;
  58                                 }
  59
  60                                 sock_table->mask = size - 1;
  61                         } else
  62                                 sock_table = orig_sock_table;
  63
  64                         for (i = 0; i < size; i++)
  65                                 sock_table->ents[i] = RPS_NO_CPU;
  66                 } else
  67                         sock_table = NULL;
  68
  69                 if (sock_table != orig_sock_table) {
  70                         rcu_assign_pointer(rps_sock_flow_table, sock_table);
  71                         synchronize_rcu();
  72                         vfree(orig_sock_table);
  73                 }
  74         }
  75
  76         mutex_unlock(&sock_flow_mutex);
  77
  78         return ret;
  79 }
  80 #endif /* CONFIG_RPS */
  81
  82 static struct ctl_table net_core_table[] = {
  83 #ifdef CONFIG_NET
  84         {
  85                 .procname       = "wmem_max",
  86                 .data           = &sysctl_wmem_max,
  87                 .maxlen         = sizeof(int),
  88                 .mode           = 0644,
  89                 .proc_handler   = proc_dointvec
  90         },
  91         {
  92                 .procname       = "rmem_max",
  93                 .data           = &sysctl_rmem_max,
  94                 .maxlen         = sizeof(int),
  95                 .mode           = 0644,
  96                 .proc_handler   = proc_dointvec
  97         },
  98         {
  99                 .procname       = "wmem_default",
 100                 .data           = &sysctl_wmem_default,
 101                 .maxlen         = sizeof(int),
 102                 .mode           = 0644,
 103                 .proc_handler   = proc_dointvec
 104         },
 105         {
 106                 .procname       = "rmem_default",
 107                 .data           = &sysctl_rmem_default,
 108                 .maxlen         = sizeof(int),
 109                 .mode           = 0644,
 110                 .proc_handler   = proc_dointvec
 111         },
 112         {
 113                 .procname       = "dev_weight",
 114                 .data           = &weight_p,
 115                 .maxlen         = sizeof(int),
 116                 .mode           = 0644,
 117                 .proc_handler   = proc_dointvec
 118         },
 119         {
 120                 .procname       = "netdev_max_backlog",
 121                 .data           = &netdev_max_backlog,
 122                 .maxlen         = sizeof(int),
 123                 .mode           = 0644,
 124                 .proc_handler   = proc_dointvec
 125         },
 126 #ifdef CONFIG_BPF_JIT
 127         {
 128                 .procname       = "bpf_jit_enable",
 129                 .data           = &bpf_jit_enable,
 130                 .maxlen         = sizeof(int),
 131                 .mode           = 0644,
 132                 .proc_handler   = proc_dointvec
 133         },
 134 #endif
 135         {
 136                 .procname       = "netdev_tstamp_prequeue",
 137                 .data           = &netdev_tstamp_prequeue,
 138                 .maxlen         = sizeof(int),
 139                 .mode           = 0644,
 140                 .proc_handler   = proc_dointvec
 141         },
 142         {
 143                 .procname       = "message_cost",
 144                 .data           = &net_ratelimit_state.interval,
 145                 .maxlen         = sizeof(int),
 146                 .mode           = 0644,
 147                 .proc_handler   = proc_dointvec_jiffies,
 148         },
 149         {
 150                 .procname       = "message_burst",
 151                 .data           = &net_ratelimit_state.burst,
 152                 .maxlen         = sizeof(int),
 153                 .mode           = 0644,
 154                 .proc_handler   = proc_dointvec,
 155         },
 156         {
 157                 .procname       = "optmem_max",
 158                 .data           = &sysctl_optmem_max,
 159                 .maxlen         = sizeof(int),
 160                 .mode           = 0644,
 161                 .proc_handler   = proc_dointvec
 162         },
 163 #ifdef CONFIG_RPS
 164         {
 165                 .procname       = "rps_sock_flow_entries",
 166                 .maxlen         = sizeof(int),
 167                 .mode           = 0644,
 168                 .proc_handler   = rps_sock_flow_sysctl
 169         },
 170 #endif
 171 #endif /* CONFIG_NET */
 172         {
 173                 .procname       = "netdev_budget",
 174                 .data           = &netdev_budget,
 175                 .maxlen         = sizeof(int),
 176                 .mode           = 0644,
 177                 .proc_handler   = proc_dointvec
 178         },
 179         {
 180                 .procname       = "warnings",
 181                 .data           = &net_msg_warn,
 182                 .maxlen         = sizeof(int),
 183                 .mode           = 0644,
 184                 .proc_handler   = proc_dointvec
 185         },
 186         { }
 187 };
 188
 189 static struct ctl_table netns_core_table[] = {
 190         {
 191                 .procname       = "somaxconn",
 192                 .data           = &init_net.core.sysctl_somaxconn,
 193                 .maxlen         = sizeof(int),
 194                 .mode           = 0644,
 195                 .proc_handler   = proc_dointvec
 196         },
 197         { }
 198 };
 199
 200 __net_initdata struct ctl_path net_core_path[] = {
 201         { .procname = "net", },
 202         { .procname = "core", },
 203         { },
 204 };
 205
 206 static __net_init int sysctl_core_net_init(struct net *net)
 207 {
 208         struct ctl_table *tbl;
 209
 210         net->core.sysctl_somaxconn = SOMAXCONN;
 211
 212         tbl = netns_core_table;
 213         if (!net_eq(net, &init_net)) {
 214                 tbl = kmemdup(tbl, sizeof(netns_core_table), GFP_KERNEL);
 215                 if (tbl == NULL)
 216                         goto err_dup;
 217
 218                 tbl[0].data = &net->core.sysctl_somaxconn;
 219         }
 220
 221         net->core.sysctl_hdr = register_net_sysctl_table(net,
 222                         net_core_path, tbl);
 223         if (net->core.sysctl_hdr == NULL)
 224                 goto err_reg;
 225
 226         return 0;
 227
 228 err_reg:
 229         if (tbl != netns_core_table)
 230                 kfree(tbl);
 231 err_dup:
 232         return -ENOMEM;
 233 }
 234
 235 static __net_exit void sysctl_core_net_exit(struct net *net)
 236 {
 237         struct ctl_table *tbl;
 238
 239         tbl = net->core.sysctl_hdr->ctl_table_arg;
 240         unregister_net_sysctl_table(net->core.sysctl_hdr);
 241         BUG_ON(tbl == netns_core_table);
 242         kfree(tbl);
 243 }
 244
 245 static __net_initdata struct pernet_operations sysctl_core_ops = {
 246         .init = sysctl_core_net_init,
 247         .exit = sysctl_core_net_exit,
 248 };
 249
 250 static __init int sysctl_core_init(void)
 251 {
 252         static struct ctl_table empty[1];
 253
 254         register_sysctl_paths(net_core_path, empty);
 255         register_net_sysctl_rotable(net_core_path, net_core_table);
 256         return register_pernet_subsys(&sysctl_core_ops);
 257 }
 258
 259 fs_initcall(sysctl_core_init);