From f77d602124d865c38705df7fa25c03de9c284ad2 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 9 May 2013 10:28:16 +0000 Subject: ipv6: do not clear pinet6 field We have seen multiple NULL dereferences in __inet6_lookup_established() After analysis, I found that inet6_sk() could be NULL while the check for sk_family == AF_INET6 was true. Bug was added in linux-2.6.29 when RCU lookups were introduced in UDP and TCP stacks. Once an IPv6 socket, using SLAB_DESTROY_BY_RCU is inserted in a hash table, we no longer can clear pinet6 field. This patch extends logic used in commit fcbdf09d9652c891 ("net: fix nulls list corruptions in sk_prot_alloc") TCP/UDP/UDPLite IPv6 protocols provide their own .clear_sk() method to make sure we do not clear pinet6 field. At socket clone phase, we do not really care, as cloning the parent (non NULL) pinet6 is not adding a fatal race. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv6/udplite.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/ipv6/udplite.c') diff --git a/net/ipv6/udplite.c b/net/ipv6/udplite.c index 1d08e21d9f69..dfcc4be46898 100644 --- a/net/ipv6/udplite.c +++ b/net/ipv6/udplite.c @@ -56,7 +56,7 @@ struct proto udplitev6_prot = { .compat_setsockopt = compat_udpv6_setsockopt, .compat_getsockopt = compat_udpv6_getsockopt, #endif - .clear_sk = sk_prot_clear_portaddr_nulls, + .clear_sk = udp_v6_clear_sk, }; static struct inet_protosw udplite6_protosw = { -- cgit v1.2.3