Based on comments from Xin, even after fixes for our recent syzbot report of cookie memory leaks, its possible to get a resend of an INIT chunk which would lead to us leaking cookie memory.
To ensure that we don't leak cookie memory, free any previously allocated cookie first. Signed-off-by: Neil Horman <nhor...@tuxdriver.com> CC: Marcelo Ricardo Leitner <marcelo.leit...@gmail.com> CC: Xin Long <lucien....@gmail.com> CC: "David S. Miller" <da...@davemloft.net> CC: netdev@vger.kernel.org --- net/sctp/sm_make_chunk.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c index f17908f5c4f3..21f7faf032e5 100644 --- a/net/sctp/sm_make_chunk.c +++ b/net/sctp/sm_make_chunk.c @@ -2583,6 +2583,8 @@ static int sctp_process_param(struct sctp_association *asoc, case SCTP_PARAM_STATE_COOKIE: asoc->peer.cookie_len = ntohs(param.p->length) - sizeof(struct sctp_paramhdr); + if (asoc->peer.cookie) + kfree(asoc->peer.cookie); asoc->peer.cookie = kmemdup(param.cookie->body, asoc->peer.cookie_len, gfp); if (!asoc->peer.cookie) retval = 0; -- 2.20.1