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
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
---
net/sctp/sm_make_chunk.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index f17908f5c4f3..9b0e5b0d701a 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;
@@ -2647,6 +2649,8 @@ static int sctp_process_param(struct sctp_association *asoc,
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) {
@@ -2660,6 +2664,8 @@ static int sctp_process_param(struct sctp_association *asoc,
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) {
@@ -2675,6 +2681,8 @@ static int sctp_process_param(struct sctp_association *asoc,
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)
--
2.20.1
