From 0cc68d05c0049f537e00ee86eb5018a8f0992a0c Mon Sep 17 00:00:00 2001 From: "Ahmed S. Darwish" Date: Tue, 16 Mar 2021 11:56:29 +0100 Subject: net: xfrm: Localize sequence counter per network namespace [ Upstream commit e88add19f68191448427a6e4eb059664650a837f ] A sequence counter write section must be serialized or its internal state can get corrupted. The "xfrm_state_hash_generation" seqcount is global, but its write serialization lock (net->xfrm.xfrm_state_lock) is instantiated per network namespace. The write protection is thus insufficient. To provide full protection, localize the sequence counter per network namespace instead. This should be safe as both the seqcount read and write sections access data exclusively within the network namespace. It also lays the foundation for transforming "xfrm_state_hash_generation" data type from seqcount_t to seqcount_LOCKNAME_t in further commits. Fixes: b65e3d7be06f ("xfrm: state: add sequence count to detect hash resizes") Signed-off-by: Ahmed S. Darwish Signed-off-by: Steffen Klassert Signed-off-by: Sasha Levin --- include/net/netns/xfrm.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/net/netns/xfrm.h b/include/net/netns/xfrm.h index 9991e5ef52cc..fbfa59801454 100644 --- a/include/net/netns/xfrm.h +++ b/include/net/netns/xfrm.h @@ -70,7 +70,9 @@ struct netns_xfrm { #if IS_ENABLED(CONFIG_IPV6) struct dst_ops xfrm6_dst_ops; #endif - spinlock_t xfrm_state_lock; + spinlock_t xfrm_state_lock; + seqcount_t xfrm_state_hash_generation; + spinlock_t xfrm_policy_lock; struct mutex xfrm_cfg_mutex; }; -- cgit v1.2.3