From: Neil Horman <nhorman@xxxxxxxxxxxxx> [ Upstream commit ce950f1050cece5e406a5cde723c69bba60e1b26 ] 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. Change notes v1->v2 update subsystem tag in subject (davem) repeat kfree check for peer_random and peer_hmacs (xin) v2->v3 net->sctp also free peer_chunks v3->v4 fix subject tags v4->v5 remove cut line Signed-off-by: Neil Horman <nhorman@xxxxxxxxxxxxx> Reported-by: syzbot+f7e9153b037eac9b1df8@xxxxxxxxxxxxxxxxxxxxxxxxx CC: Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx> CC: Xin Long <lucien.xin@xxxxxxxxx> CC: "David S. Miller" <davem@xxxxxxxxxxxxx> CC: netdev@xxxxxxxxxxxxxxx Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/sctp/sm_make_chunk.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/net/sctp/sm_make_chunk.c +++ b/net/sctp/sm_make_chunk.c @@ -2600,6 +2600,8 @@ do_addr_param: 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; @@ -2664,6 +2666,8 @@ do_addr_param: goto fall_through; /* Save peer's random parameter */ + if (asoc->peer.peer_random) + kfree(asoc->peer.peer_random); asoc->peer.peer_random = kmemdup(param.p, ntohs(param.p->length), gfp); if (!asoc->peer.peer_random) { @@ -2677,6 +2681,8 @@ do_addr_param: goto fall_through; /* Save peer's HMAC list */ + if (asoc->peer.peer_hmacs) + kfree(asoc->peer.peer_hmacs); asoc->peer.peer_hmacs = kmemdup(param.p, ntohs(param.p->length), gfp); if (!asoc->peer.peer_hmacs) { @@ -2692,6 +2698,8 @@ do_addr_param: if (!ep->auth_enable) goto fall_through; + if (asoc->peer.peer_chunks) + kfree(asoc->peer.peer_chunks); asoc->peer.peer_chunks = kmemdup(param.p, ntohs(param.p->length), gfp); if (!asoc->peer.peer_chunks)