In Commit 1f45f78f8e51 ("sctp: allow GSO frags to access the chunk too"), it held the chunk in sctp_ulpevent_make_rcvmsg to access it safely later in recvmsg. However, it also added sctp_chunk_put in fail_mark err path, which is only triggered before holding the chunk. syzbot reported a use-after-free crash happened on this err path, where it shouldn't call sctp_chunk_put. This patch simply removes this call. Fixes: 1f45f78f8e51 ("sctp: allow GSO frags to access the chunk too") Reported-by: syzbot+141d898c5f24489db4aa@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx> --- net/sctp/ulpevent.c | 1 - 1 file changed, 1 deletion(-) diff --git a/net/sctp/ulpevent.c b/net/sctp/ulpevent.c index 84207ad..8cb7d98 100644 --- a/net/sctp/ulpevent.c +++ b/net/sctp/ulpevent.c @@ -715,7 +715,6 @@ struct sctp_ulpevent *sctp_ulpevent_make_rcvmsg(struct sctp_association *asoc, return event; fail_mark: - sctp_chunk_put(chunk); kfree_skb(skb); fail: return NULL; -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-sctp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html