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 static int min_sndbuf = SOCK_MIN_SNDBUF;
  25 static int min_rcvbuf = SOCK_MIN_RCVBUF;
  26
  27 #ifdef CONFIG_RPS
  28 static int rps_sock_flow_sysctl(ctl_table *table, int write,
  29                                 void __user *buffer, size_t *lenp, loff_t *ppos)
  30 {
  31         unsigned int orig_size, size;
  32         int ret, i;
  33         ctl_table tmp = {
  34                 .data = &size,
  35                 .maxlen = sizeof(size),
  36                 .mode = table->mode
  37         };
  38         struct rps_sock_flow_table *orig_sock_table, *sock_table;
  39         static DEFINE_MUTEX(sock_flow_mutex);
  40
  41         mutex_lock(&sock_flow_mutex);
  42
  43         orig_sock_table = rcu_dereference_protected(rps_sock_flow_table,
  44                                         lockdep_is_held(&sock_flow_mutex));
  45         size = orig_size = orig_sock_table ? orig_sock_table->mask + 1 : 0;
  46
  47         ret = proc_dointvec(&tmp, write, buffer, lenp, ppos);
  48
  49         if (write) {
  50                 if (size) {
  51                         if (size > 1<<30) {
  52                                 /* Enforce limit to prevent overflow */
  53                                 mutex_unlock(&sock_flow_mutex);
  54                                 return -EINVAL;
  55                         }
  56                         size = roundup_pow_of_two(size);
  57                         if (size != orig_size) {
  58                                 sock_table =
  59                                     vmalloc(RPS_SOCK_FLOW_TABLE_SIZE(size));
  60                                 if (!sock_table) {
  61                                         mutex_unlock(&sock_flow_mutex);
  62                                         return -ENOMEM;
  63                                 }
  64
  65                                 sock_table->mask = size - 1;
  66                         } else
  67                                 sock_table = orig_sock_table;
  68
  69                         for (i = 0; i < size; i++)
  70                                 sock_table->ents[i] = RPS_NO_CPU;
  71                 } else
  72                         sock_table = NULL;
  73
  74                 if (sock_table != orig_sock_table) {
  75                         rcu_assign_pointer(rps_sock_flow_table, sock_table);
  76                         synchronize_rcu();
  77                         vfree(orig_sock_table);
  78                 }
  79         }
  80
  81         mutex_unlock(&sock_flow_mutex);
  82
  83         return ret;
  84 }
  85 #endif /* CONFIG_RPS */
  86
  87 static struct ctl_table net_core_table[] = {
  88 #ifdef CONFIG_NET
  89         {
  90                 .procname       = "wmem_max",
  91                 .data           = &sysctl_wmem_max,
  92                 .maxlen         = sizeof(int),
  93                 .mode           = 0644,
  94                 .proc_handler   = proc_dointvec_minmax,
  95                 .extra1         = &min_sndbuf,
  96         },
  97         {
  98                 .procname       = "rmem_max",
  99                 .data           = &sysctl_rmem_max,
 100                 .maxlen         = sizeof(int),
 101                 .mode           = 0644,
 102                 .proc_handler   = proc_dointvec_minmax,
 103                 .extra1         = &min_rcvbuf,
 104         },
 105         {
 106                 .procname       = "wmem_default",
 107                 .data           = &sysctl_wmem_default,
 108                 .maxlen         = sizeof(int),
 109                 .mode           = 0644,
 110                 .proc_handler   = proc_dointvec_minmax,
 111                 .extra1         = &min_sndbuf,
 112         },
 113         {
 114                 .procname       = "rmem_default",
 115                 .data           = &sysctl_rmem_default,
 116                 .maxlen         = sizeof(int),
 117                 .mode           = 0644,
 118                 .proc_handler   = proc_dointvec_minmax,
 119                 .extra1         = &min_rcvbuf,
 120         },
 121         {
 122                 .procname       = "dev_weight",
 123                 .data           = &weight_p,
 124                 .maxlen         = sizeof(int),
 125                 .mode           = 0644,
 126                 .proc_handler   = proc_dointvec
 127         },
 128         {
 129                 .procname       = "netdev_max_backlog",
 130                 .data           = &netdev_max_backlog,
 131                 .maxlen         = sizeof(int),
 132                 .mode           = 0644,
 133                 .proc_handler   = proc_dointvec
 134         },
 135 #ifdef CONFIG_BPF_JIT
 136         {
 137                 .procname       = "bpf_jit_enable",
 138                 .data           = &bpf_jit_enable,
 139                 .maxlen         = sizeof(int),
 140                 .mode           = 0644,
 141                 .proc_handler   = proc_dointvec
 142         },
 143 #endif
 144         {
 145                 .procname       = "netdev_tstamp_prequeue",
 146                 .data           = &netdev_tstamp_prequeue,
 147                 .maxlen         = sizeof(int),
 148                 .mode           = 0644,
 149                 .proc_handler   = proc_dointvec
 150         },
 151         {
 152                 .procname       = "message_cost",
 153                 .data           = &net_ratelimit_state.interval,
 154                 .maxlen         = sizeof(int),
 155                 .mode           = 0644,
 156                 .proc_handler   = proc_dointvec_jiffies,
 157         },
 158         {
 159                 .procname       = "message_burst",
 160                 .data           = &net_ratelimit_state.burst,
 161                 .maxlen         = sizeof(int),
 162                 .mode           = 0644,
 163                 .proc_handler   = proc_dointvec,
 164         },
 165         {
 166                 .procname       = "optmem_max",
 167                 .data           = &sysctl_optmem_max,
 168                 .maxlen         = sizeof(int),
 169                 .mode           = 0644,
 170                 .proc_handler   = proc_dointvec
 171         },
 172 #ifdef CONFIG_RPS
 173         {
 174                 .procname       = "rps_sock_flow_entries",
 175                 .maxlen         = sizeof(int),
 176                 .mode           = 0644,
 177                 .proc_handler   = rps_sock_flow_sysctl
 178         },
 179 #endif
 180 #endif /* CONFIG_NET */
 181         {
 182                 .procname       = "netdev_budget",
 183                 .data           = &netdev_budget,
 184                 .maxlen         = sizeof(int),
 185                 .mode           = 0644,
 186                 .proc_handler   = proc_dointvec
 187         },
 188         {
 189                 .procname       = "warnings",
 190                 .data           = &net_msg_warn,
 191                 .maxlen         = sizeof(int),
 192                 .mode           = 0644,
 193                 .proc_handler   = proc_dointvec
 194         },
 195         { }
 196 };
 197
 198 static struct ctl_table netns_core_table[] = {
 199         {
 200                 .procname       = "somaxconn",
 201                 .data           = &init_net.core.sysctl_somaxconn,
 202                 .maxlen         = sizeof(int),
 203                 .mode           = 0644,
 204                 .extra1         = &zero,
 205                 .extra2         = &ushort_max,
 206                 .proc_handler   = proc_dointvec_minmax
 207         },
 208         { }
 209 };
 210
 211 __net_initdata struct ctl_path net_core_path[] = {
 212         { .procname = "net", },
 213         { .procname = "core", },
 214         { },
 215 };
 216
 217 static __net_init int sysctl_core_net_init(struct net *net)
 218 {
 219         struct ctl_table *tbl;
 220
 221         net->core.sysctl_somaxconn = SOMAXCONN;
 222
 223         tbl = netns_core_table;
 224         if (!net_eq(net, &init_net)) {
 225                 tbl = kmemdup(tbl, sizeof(netns_core_table), GFP_KERNEL);
 226                 if (tbl == NULL)
 227                         goto err_dup;
 228
 229                 tbl[0].data = &net->core.sysctl_somaxconn;
 230         }
 231
 232         net->core.sysctl_hdr = register_net_sysctl_table(net,
 233                         net_core_path, tbl);
 234         if (net->core.sysctl_hdr == NULL)
 235                 goto err_reg;
 236
 237         return 0;
 238
 239 err_reg:
 240         if (tbl != netns_core_table)
 241                 kfree(tbl);
 242 err_dup:
 243         return -ENOMEM;
 244 }
 245
 246 static __net_exit void sysctl_core_net_exit(struct net *net)
 247 {
 248         struct ctl_table *tbl;
 249
 250         tbl = net->core.sysctl_hdr->ctl_table_arg;
 251         unregister_net_sysctl_table(net->core.sysctl_hdr);
 252         BUG_ON(tbl == netns_core_table);
 253         kfree(tbl);
 254 }
 255
 256 static __net_initdata struct pernet_operations sysctl_core_ops = {
 257         .init = sysctl_core_net_init,
 258         .exit = sysctl_core_net_exit,
 259 };
 260
 261 static __init int sysctl_core_init(void)
 262 {
 263         static struct ctl_table empty[1];
 264
 265         register_sysctl_paths(net_core_path, empty);
 266         register_net_sysctl_rotable(net_core_path, net_core_table);
 267         return register_pernet_subsys(&sysctl_core_ops);
 268 }
 269
 270 fs_initcall(sysctl_core_init);