diff options
authorNeil Horman <nhorman@tuxdriver.com>2019-06-13 06:35:59 -0400
committerPaul Gortmaker <paul.gortmaker@windriver.com>2019-09-16 12:21:30 -0400
commit705404bef06bacb7838685894082a37a768fe834 (patch)
parentcfcd9ab3bedb3cc3a18894a4d753059857eb0ce4 (diff)
sctp: Free cookie before we memdup a new one
commit ce950f1050cece5e406a5cde723c69bba60e1b26 upstream. 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@tuxdriver.com> Reported-by: syzbot+f7e9153b037eac9b1df8@syzkaller.appspotmail.com CC: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> CC: Xin Long <lucien.xin@gmail.com> CC: "David S. Miller" <davem@davemloft.net> CC: netdev@vger.kernel.org Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
1 files changed, 8 insertions, 0 deletions
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index ae65a1cfa596..fb546b2d67ca 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -2600,6 +2600,8 @@ do_addr_param:
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)