From 91341fa0003befd097e190ec2a4bf63ad957c49a Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 13 Jan 2022 01:22:29 -0800 Subject: inet: frags: annotate races around fqdir->dead and fqdir->high_thresh Both fields can be read/written without synchronization, add proper accessors and documentation. Fixes: d5dd88794a13 ("inet: fix various use-after-free in defrags units") Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/ipv6_frag.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/net/ipv6_frag.h') diff --git a/include/net/ipv6_frag.h b/include/net/ipv6_frag.h index 851029ecff13..0a4779175a52 100644 --- a/include/net/ipv6_frag.h +++ b/include/net/ipv6_frag.h @@ -67,7 +67,8 @@ ip6frag_expire_frag_queue(struct net *net, struct frag_queue *fq) struct sk_buff *head; rcu_read_lock(); - if (fq->q.fqdir->dead) + /* Paired with the WRITE_ONCE() in fqdir_pre_exit(). */ + if (READ_ONCE(fq->q.fqdir->dead)) goto out_rcu_unlock; spin_lock(&fq->q.lock); -- cgit v1.2.3