From bc8e0adff343d992ca76d871e8b5e6cb86e1fad9 Mon Sep 17 00:00:00 2001 From: "Ahmed S. Darwish" Date: Tue, 16 Mar 2021 11:56:30 +0100 Subject: net: xfrm: Use sequence counter with associated spinlock A sequence counter write section must be serialized or its internal state can get corrupted. A plain seqcount_t does not contain the information of which lock must be held to guaranteee write side serialization. For xfrm_state_hash_generation, use seqcount_spinlock_t instead of plain seqcount_t. This allows to associate the spinlock used for write serialization with the sequence counter. It thus enables lockdep to verify that the write serialization lock is indeed held before entering the sequence counter write section. If lockdep is disabled, this lock association is compiled out and has neither storage size nor runtime overhead. Signed-off-by: Ahmed S. Darwish Signed-off-by: Steffen Klassert --- net/xfrm/xfrm_state.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/xfrm') diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c index ffd315cff984..4496f7efa220 100644 --- a/net/xfrm/xfrm_state.c +++ b/net/xfrm/xfrm_state.c @@ -2665,7 +2665,8 @@ int __net_init xfrm_state_init(struct net *net) net->xfrm.state_num = 0; INIT_WORK(&net->xfrm.state_hash_work, xfrm_hash_resize); spin_lock_init(&net->xfrm.xfrm_state_lock); - seqcount_init(&net->xfrm.xfrm_state_hash_generation); + seqcount_spinlock_init(&net->xfrm.xfrm_state_hash_generation, + &net->xfrm.xfrm_state_lock); return 0; out_byspi: -- cgit v1.2.3-59-g8ed1b