[PATCH] sctp: fix refcount bug in sctp_wfree
From: Qiujun Huang <hidden>
Date: 2020-03-16 03:53:31
Also in:
linux-sctp, lkml
Subsystem:
networking [general], sctp protocol, the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Marcelo Ricardo Leitner, Xin Long, Linus Torvalds
Do accounting for skb's real sk. In some case skb->sk != asoc->base.sk. Reported-and-tested-by: syzbot+cea71eec5d6de256d54d@syzkaller.appspotmail.com Signed-off-by: Qiujun Huang <redacted> --- net/sctp/socket.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 1b56fc4..5f5c28b 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c@@ -9080,7 +9080,7 @@ static void sctp_wfree(struct sk_buff *skb) { struct sctp_chunk *chunk = skb_shinfo(skb)->destructor_arg; struct sctp_association *asoc = chunk->asoc; - struct sock *sk = asoc->base.sk; + struct sock *sk = skb->sk; sk_mem_uncharge(sk, skb->truesize); sk->sk_wmem_queued -= skb->truesize + sizeof(struct sctp_chunk);
@@ -9109,7 +9109,7 @@ static void sctp_wfree(struct sk_buff *skb) } sock_wfree(skb); - sctp_wake_up_waiters(sk, asoc); + sctp_wake_up_waiters(asoc->base.sk, asoc); sctp_association_put(asoc); }
--
1.8.3.1