Message ID | 20190610163456.7778-1-nhorman@tuxdriver.com |
---|---|
State | Changes Requested |
Delegated to: | David Miller |
Headers | show |
Series | Free cookie before we memdup a new one | expand |
From: Neil Horman <nhorman@tuxdriver.com> Date: Mon, 10 Jun 2019 12:34:56 -0400 > 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 <nhorman@tuxdriver.com> Please post with an appropriate subsystem prefix in the Subject. Thank you.
On Tue, Jun 11, 2019 at 12:35 AM Neil Horman <nhorman@tuxdriver.com> wrote: > > 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. Hi, Neil, I think we should also do the same thing to the other 2 kmemdups in sctp_process_param(): asoc->peer.peer_random asoc->peer.peer_hmacs > > Signed-off-by: Neil Horman <nhorman@tuxdriver.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 > --- > 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 >
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;
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 <nhorman@tuxdriver.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 --- net/sctp/sm_make_chunk.c | 2 ++ 1 file changed, 2 insertions(+)