net ipv6: Fix duplicate /proc/sys/net/ipv6/neigh directory entries.

When I was fixing issues with unregisgtering tables under /proc/sys/net/ipv6/neigh
by adding a mount point it appears I missed a critical ordering issue, in the
ipv6 initialization.  I had not realized that ipv6_sysctl_register is called
at the very end of the ipv6 initialization and in particular after we call
neigh_sysctl_register from ndisc_init.

"neigh" needs to be initialized in ipv6_static_sysctl_register which is
the first ipv6 table to initialized, and definitely before ndisc_init.
This removes the weirdness of duplicate tables while still providing a
"neigh" mount point which prevents races in sysctl unregistering.

This was initially reported at https://bugzilla.kernel.org/show_bug.cgi?id=31232
Reported-by: sunkan@zappa.cx
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric W. Biederman 2011-03-21 18:23:34 -07:00 committed by David S. Miller
parent d5cd92448f
commit 9d2a8fa96a

View file

@ -17,6 +17,16 @@
static struct ctl_table empty[1]; static struct ctl_table empty[1];
static ctl_table ipv6_static_skeleton[] = {
{
.procname = "neigh",
.maxlen = 0,
.mode = 0555,
.child = empty,
},
{ }
};
static ctl_table ipv6_table_template[] = { static ctl_table ipv6_table_template[] = {
{ {
.procname = "route", .procname = "route",
@ -37,12 +47,6 @@ static ctl_table ipv6_table_template[] = {
.mode = 0644, .mode = 0644,
.proc_handler = proc_dointvec .proc_handler = proc_dointvec
}, },
{
.procname = "neigh",
.maxlen = 0,
.mode = 0555,
.child = empty,
},
{ } { }
}; };
@ -160,7 +164,7 @@ static struct ctl_table_header *ip6_base;
int ipv6_static_sysctl_register(void) int ipv6_static_sysctl_register(void)
{ {
ip6_base = register_sysctl_paths(net_ipv6_ctl_path, empty); ip6_base = register_sysctl_paths(net_ipv6_ctl_path, ipv6_static_skeleton);
if (ip6_base == NULL) if (ip6_base == NULL)
return -ENOMEM; return -ENOMEM;
return 0; return 0;