ipv6: compare sernum when walking fib for /proc/net/ipv6_route as safety net
authorHannes Frederic Sowa <hannes@stressinduktion.org>
Sat, 21 Sep 2013 14:56:10 +0000 (16:56 +0200)
committerDavid S. Miller <davem@davemloft.net>
Fri, 27 Sep 2013 21:32:17 +0000 (17:32 -0400)
commit0a67d3efa4e3223452c96d8c962d7c077ef80ff3
tree7a6690e9cf93deb539b25dd006f11e555c3ae3a6
parent8d2ca1d7b5c3e63b3a8a81ae99015b615c5f2bf7
ipv6: compare sernum when walking fib for /proc/net/ipv6_route as safety net

This patch provides an additional safety net against NULL
pointer dereferences while walking the fib trie for the new
/proc/net/ipv6_route walkers. I never needed it myself and am unsure
if it is needed at all, but the same checks where introduced in
2bec5a369ee79576a3eea2c23863325089785a2c ("ipv6: fib: fix crash when
changing large fib while dumping it") to fix NULL pointer bugs.

This patch is separated from the first patch to make it easier to revert
if we are sure we can drop this logic.

Cc: Ben Greear <greearb@candelatech.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/ipv6/ip6_fib.c