Do accounting for skb's real sk. In some case skb->sk != asoc->base.sk: migrate routing sctp_check_transmitted routing ------------ --------------- lock_sock_nested(); mv the transmitted skb to the it's local tlist sctp_for_each_tx_datachunk( sctp_clear_owner_w); sctp_assoc_migrate(); sctp_for_each_tx_datachunk( sctp_set_owner_w); put the skb back to the assoc lists ---------------------------------------------------- The skbs which held bysctp_check_transmitted were not changed to newsk. They were not dealt with by sctp_for_each_tx_datachunk (sctp_clear_owner_w/sctp_set_owner_w). It looks only trouble here so handling it in sctp_wfree is enough. Reported-and-tested-by: syzbot+cea71eec5d6de256d54d@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Qiujun Huang <hqjagain@xxxxxxxxx> --- 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 1b56fc440606..5f5c28b30e25 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); } -- 2.17.1