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 static int zero = 0;
  23 static int ushort_max = USHRT_MAX;
  24
  25 #ifdef CONFIG_RPS
  26 static int rps_sock_flow_sysctl(ctl_table *table, int write,
  27                                 void __user *buffer, size_t *lenp, loff_t *ppos)
  28 {
  29         unsigned int orig_size, size;
  30         int ret, i;
  31         ctl_table tmp = {
  32                 .data = &size,
  33                 .maxlen = sizeof(size),
  34                 .mode = table->mode
  35         };
  36         struct rps_sock_flow_table *orig_sock_table, *sock_table;
  37         static DEFINE_MUTEX(sock_flow_mutex);
  38
  39         mutex_lock(&sock_flow_mutex);
  40
  41         orig_sock_table = rcu_dereference_protected(rps_sock_flow_table,
  42                                         lockdep_is_held(&sock_flow_mutex));
  43         size = orig_size = orig_sock_table ? orig_sock_table->mask + 1 : 0;
  44
  45         ret = proc_dointvec(&tmp, write, buffer, lenp, ppos);
  46
  47         if (write) {
  48                 if (size) {
  49                         if (size > 1<<30) {
  50                                 /* Enforce limit to prevent overflow */
  51                                 mutex_unlock(&sock_flow_mutex);
  52                                 return -EINVAL;
  53                         }
  54                         size = roundup_pow_of_two(size);
  55                         if (size != orig_size) {
  56                                 sock_table =
  57                                     vmalloc(RPS_SOCK_FLOW_TABLE_SIZE(size));
  58                                 if (!sock_table) {
  59                                         mutex_unlock(&sock_flow_mutex);
  60                                         return -ENOMEM;
  61                                 }
  62
  63                                 sock_table->mask = size - 1;
  64                         } else
  65                                 sock_table = orig_sock_table;
  66
  67                         for (i = 0; i < size; i++)
  68                                 sock_table->ents[i] = RPS_NO_CPU;
  69                 } else
  70                         sock_table = NULL;
  71
  72                 if (sock_table != orig_sock_table) {
  73                         rcu_assign_pointer(rps_sock_flow_table, sock_table);
  74                         synchronize_rcu();
  75                         vfree(orig_sock_table);
  76                 }
  77         }
  78
  79         mutex_unlock(&sock_flow_mutex);
  80
  81         return ret;
  82 }
  83 #endif /* CONFIG_RPS */
  84
  85 static struct ctl_table net_core_table[] = {
  86 #ifdef CONFIG_NET
  87         {
  88                 .procname       = "wmem_max",
  89                 .data           = &sysctl_wmem_max,
  90                 .maxlen         = sizeof(int),
  91                 .mode           = 0644,
  92                 .proc_handler   = proc_dointvec
  93         },
  94         {
  95                 .procname       = "rmem_max",
  96                 .data           = &sysctl_rmem_max,
  97                 .maxlen         = sizeof(int),
  98                 .mode           = 0644,
  99                 .proc_handler   = proc_dointvec
 100         },
 101         {
 102                 .procname       = "wmem_default",
 103                 .data           = &sysctl_wmem_default,
 104                 .maxlen         = sizeof(int),
 105                 .mode           = 0644,
 106                 .proc_handler   = proc_dointvec
 107         },
 108         {
 109                 .procname       = "rmem_default",
 110                 .data           = &sysctl_rmem_default,
 111                 .maxlen         = sizeof(int),
 112                 .mode           = 0644,
 113                 .proc_handler   = proc_dointvec
 114         },
 115         {
 116                 .procname       = "dev_weight",
 117                 .data           = &weight_p,
 118                 .maxlen         = sizeof(int),
 119                 .mode           = 0644,
 120                 .proc_handler   = proc_dointvec
 121         },
 122         {
 123                 .procname       = "netdev_max_backlog",
 124                 .data           = &netdev_max_backlog,
 125                 .maxlen         = sizeof(int),
 126                 .mode           = 0644,
 127                 .proc_handler   = proc_dointvec
 128         },
 129 #ifdef CONFIG_BPF_JIT
 130         {
 131                 .procname       = "bpf_jit_enable",
 132                 .data           = &bpf_jit_enable,
 133                 .maxlen         = sizeof(int),
 134                 .mode           = 0644,
 135                 .proc_handler   = proc_dointvec
 136         },
 137 #endif
 138         {
 139                 .procname       = "netdev_tstamp_prequeue",
 140                 .data           = &netdev_tstamp_prequeue,
 141                 .maxlen         = sizeof(int),
 142                 .mode           = 0644,
 143                 .proc_handler   = proc_dointvec
 144         },
 145         {
 146                 .procname       = "message_cost",
 147                 .data           = &net_ratelimit_state.interval,
 148                 .maxlen         = sizeof(int),
 149                 .mode           = 0644,
 150                 .proc_handler   = proc_dointvec_jiffies,
 151         },
 152         {
 153                 .procname       = "message_burst",
 154                 .data           = &net_ratelimit_state.burst,
 155                 .maxlen         = sizeof(int),
 156                 .mode           = 0644,
 157                 .proc_handler   = proc_dointvec,
 158         },
 159         {
 160                 .procname       = "optmem_max",
 161                 .data           = &sysctl_optmem_max,
 162                 .maxlen         = sizeof(int),
 163                 .mode           = 0644,
 164                 .proc_handler   = proc_dointvec
 165         },
 166 #ifdef CONFIG_RPS
 167         {
 168                 .procname       = "rps_sock_flow_entries",
 169                 .maxlen         = sizeof(int),
 170                 .mode           = 0644,
 171                 .proc_handler   = rps_sock_flow_sysctl
 172         },
 173 #endif
 174 #endif /* CONFIG_NET */
 175         {
 176                 .procname       = "netdev_budget",
 177                 .data           = &netdev_budget,
 178                 .maxlen         = sizeof(int),
 179                 .mode           = 0644,
 180                 .proc_handler   = proc_dointvec
 181         },
 182         {
 183                 .procname       = "warnings",
 184                 .data           = &net_msg_warn,
 185                 .maxlen         = sizeof(int),
 186                 .mode           = 0644,
 187                 .proc_handler   = proc_dointvec
 188         },
 189         { }
 190 };
 191
 192 static struct ctl_table netns_core_table[] = {
 193         {
 194                 .procname       = "somaxconn",
 195                 .data           = &init_net.core.sysctl_somaxconn,
 196                 .maxlen         = sizeof(int),
 197                 .mode           = 0644,
 198                 .extra1         = &zero,
 199                 .extra2         = &ushort_max,
 200                 .proc_handler   = proc_dointvec_minmax
 201         },
 202         { }
 203 };
 204
 205 __net_initdata struct ctl_path net_core_path[] = {
 206         { .procname = "net", },
 207         { .procname = "core", },
 208         { },
 209 };
 210
 211 static __net_init int sysctl_core_net_init(struct net *net)
 212 {
 213         struct ctl_table *tbl;
 214
 215         net->core.sysctl_somaxconn = SOMAXCONN;
 216
 217         tbl = netns_core_table;
 218         if (!net_eq(net, &init_net)) {
 219                 tbl = kmemdup(tbl, sizeof(netns_core_table), GFP_KERNEL);
 220                 if (tbl == NULL)
 221                         goto err_dup;
 222
 223                 tbl[0].data = &net->core.sysctl_somaxconn;
 224         }
 225
 226         net->core.sysctl_hdr = register_net_sysctl_table(net,
 227                         net_core_path, tbl);
 228         if (net->core.sysctl_hdr == NULL)
 229                 goto err_reg;
 230
 231         return 0;
 232
 233 err_reg:
 234         if (tbl != netns_core_table)
 235                 kfree(tbl);
 236 err_dup:
 237         return -ENOMEM;
 238 }
 239
 240 static __net_exit void sysctl_core_net_exit(struct net *net)
 241 {
 242         struct ctl_table *tbl;
 243
 244         tbl = net->core.sysctl_hdr->ctl_table_arg;
 245         unregister_net_sysctl_table(net->core.sysctl_hdr);
 246         BUG_ON(tbl == netns_core_table);
 247         kfree(tbl);
 248 }
 249
 250 static __net_initdata struct pernet_operations sysctl_core_ops = {
 251         .init = sysctl_core_net_init,
 252         .exit = sysctl_core_net_exit,
 253 };
 254
 255 static __init int sysctl_core_init(void)
 256 {
 257         static struct ctl_table empty[1];
 258
 259         register_sysctl_paths(net_core_path, empty);
 260         register_net_sysctl_rotable(net_core_path, net_core_table);
 261         return register_pernet_subsys(&sysctl_core_ops);
 262 }
 263
 264 fs_initcall(sysctl_core_init);