sysctl: fix neighbour table sysctls.

- In ipv6 ndisc_ifinfo_syctl_change so it doesn't depend on binary
  sysctl names for a function that works with proc.

- In neighbour.c reorder the table to put the possibly unused entries
  at the end so we can remove them by terminating the table early.

- In neighbour.c kill the entries with questionable binary sysctl
  handling behavior.

- In neighbour.c if we don't have a strategy routine remove the
  binary path.  So we don't the default sysctl strategy routine
  on data that is not ready for it.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alexey Dobriyan <adobriyan@sw.ru>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 39 insertions, 36 deletions

diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index cd3af59b38a1..67ba9914e52e 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -2496,7 +2496,6 @@ static struct neigh_sysctl_table {
                         .proc_handler   = &proc_dointvec,
                 },
                 {
-                        .ctl_name       = NET_NEIGH_RETRANS_TIME,
                         .procname       = "retrans_time",
                         .maxlen         = sizeof(int),
                         .mode           = 0644,
@@ -2541,27 +2540,40 @@ static struct neigh_sysctl_table {
                         .proc_handler   = &proc_dointvec,
                 },
                 {
-                        .ctl_name       = NET_NEIGH_ANYCAST_DELAY,
                         .procname       = "anycast_delay",
                         .maxlen         = sizeof(int),
                         .mode           = 0644,
                         .proc_handler   = &proc_dointvec_userhz_jiffies,
                 },
                 {
-                        .ctl_name       = NET_NEIGH_PROXY_DELAY,
                         .procname       = "proxy_delay",
                         .maxlen         = sizeof(int),
                         .mode           = 0644,
                         .proc_handler   = &proc_dointvec_userhz_jiffies,
                 },
                 {
-                        .ctl_name       = NET_NEIGH_LOCKTIME,
                         .procname       = "locktime",
                         .maxlen         = sizeof(int),
                         .mode           = 0644,
                         .proc_handler   = &proc_dointvec_userhz_jiffies,
                 },
                 {
+                        .ctl_name       = NET_NEIGH_RETRANS_TIME_MS,
+                        .procname       = "retrans_time_ms",
+                        .maxlen         = sizeof(int),
+                        .mode           = 0644,
+                        .proc_handler   = &proc_dointvec_ms_jiffies,
+                        .strategy       = &sysctl_ms_jiffies,
+                },
+                {
+                        .ctl_name       = NET_NEIGH_REACHABLE_TIME_MS,
+                        .procname       = "base_reachable_time_ms",
+                        .maxlen         = sizeof(int),
+                        .mode           = 0644,
+                        .proc_handler   = &proc_dointvec_ms_jiffies,
+                        .strategy       = &sysctl_ms_jiffies,
+                },
+                {
                         .ctl_name       = NET_NEIGH_GC_INTERVAL,
                         .procname       = "gc_interval",
                         .maxlen         = sizeof(int),
@@ -2590,22 +2602,7 @@ static struct neigh_sysctl_table {
                         .mode           = 0644,
                         .proc_handler   = &proc_dointvec,
                 },
-                {
-                        .ctl_name       = NET_NEIGH_RETRANS_TIME_MS,
-                        .procname       = "retrans_time_ms",
-                        .maxlen         = sizeof(int),
-                        .mode           = 0644,
-                        .proc_handler   = &proc_dointvec_ms_jiffies,
-                        .strategy       = &sysctl_ms_jiffies,
-                },
-                {
-                        .ctl_name       = NET_NEIGH_REACHABLE_TIME_MS,
-                        .procname       = "base_reachable_time_ms",
-                        .maxlen         = sizeof(int),
-                        .mode           = 0644,
-                        .proc_handler   = &proc_dointvec_ms_jiffies,
-                        .strategy       = &sysctl_ms_jiffies,
-                },
+                {}
         },
         .neigh_dev = {
                 {
@@ -2658,42 +2655,48 @@ int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
         t->neigh_vars[9].data  = &p->anycast_delay;
         t->neigh_vars[10].data = &p->proxy_delay;
         t->neigh_vars[11].data = &p->locktime;
+        t->neigh_vars[12].data  = &p->retrans_time;
+        t->neigh_vars[13].data  = &p->base_reachable_time;
 
         if (dev) {
                 dev_name_source = dev->name;
                 t->neigh_dev[0].ctl_name = dev->ifindex;
-                t->neigh_vars[12].procname = NULL;
-                t->neigh_vars[13].procname = NULL;
-                t->neigh_vars[14].procname = NULL;
-                t->neigh_vars[15].procname = NULL;
+                /* Terminate the table early */
+                memset(&t->neigh_vars[14], 0, sizeof(t->neigh_vars[14]));
         } else {
                 dev_name_source = t->neigh_dev[0].procname;
-                t->neigh_vars[12].data = (int *)(p + 1);
-                t->neigh_vars[13].data = (int *)(p + 1) + 1;
-                t->neigh_vars[14].data = (int *)(p + 1) + 2;
-                t->neigh_vars[15].data = (int *)(p + 1) + 3;
+                t->neigh_vars[14].data = (int *)(p + 1);
+                t->neigh_vars[15].data = (int *)(p + 1) + 1;
+                t->neigh_vars[16].data = (int *)(p + 1) + 2;
+                t->neigh_vars[17].data = (int *)(p + 1) + 3;
         }
 
-        t->neigh_vars[16].data  = &p->retrans_time;
-        t->neigh_vars[17].data  = &p->base_reachable_time;
 
         if (handler || strategy) {
                 /* RetransTime */
                 t->neigh_vars[3].proc_handler = handler;
                 t->neigh_vars[3].strategy = strategy;
                 t->neigh_vars[3].extra1 = dev;
+                if (!strategy)
+                        t->neigh_vars[3].ctl_name = CTL_UNNUMBERED;
                 /* ReachableTime */
                 t->neigh_vars[4].proc_handler = handler;
                 t->neigh_vars[4].strategy = strategy;
                 t->neigh_vars[4].extra1 = dev;
+                if (!strategy)
+                        t->neigh_vars[4].ctl_name = CTL_UNNUMBERED;
                 /* RetransTime (in milliseconds)*/
-                t->neigh_vars[16].proc_handler = handler;
-                t->neigh_vars[16].strategy = strategy;
-                t->neigh_vars[16].extra1 = dev;
+                t->neigh_vars[12].proc_handler = handler;
+                t->neigh_vars[12].strategy = strategy;
+                t->neigh_vars[12].extra1 = dev;
+                if (!strategy)
+                        t->neigh_vars[12].ctl_name = CTL_UNNUMBERED;
                 /* ReachableTime (in milliseconds) */
-                t->neigh_vars[17].proc_handler = handler;
-                t->neigh_vars[17].strategy = strategy;
-                t->neigh_vars[17].extra1 = dev;
+                t->neigh_vars[13].proc_handler = handler;
+                t->neigh_vars[13].strategy = strategy;
+                t->neigh_vars[13].extra1 = dev;
+                if (!strategy)
+                        t->neigh_vars[13].ctl_name = CTL_UNNUMBERED;
         }
 
         dev_name = kstrdup(dev_name_source, GFP_KERNEL);