From 9f6cf3abdb1e954db86f963569590444642495ff Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Thu, 10 May 2012 22:16:32 -0400 Subject: ipv4: Do not use dead fib_info entries. [ Upstream commit dccd9ecc374462e5d6a5b8f8110415a86c2213d8 ] Due to RCU lookups and RCU based release, fib_info objects can be found during lookup which have fi->fib_dead set. We must ignore these entries, otherwise we risk dereferencing the parts of the entry which are being torn down. Reported-by: Yevgen Pronenko Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- net/ipv4/fib_trie.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'net/ipv4') diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c index 3ce23f9d9363..cd2d639541bc 100644 --- a/net/ipv4/fib_trie.c +++ b/net/ipv4/fib_trie.c @@ -1372,6 +1372,8 @@ static int check_leaf(struct fib_table *tb, struct trie *t, struct leaf *l, if (fa->fa_tos && fa->fa_tos != flp->flowi4_tos) continue; + if (fi->fib_dead) + continue; if (fa->fa_info->fib_scope < flp->flowi4_scope) continue; fib_alias_accessed(fa); -- cgit v1.2.3