Re: [PATCH] sctp: fix a potential buffer overflow in sctp_sched_set_sched()
From: Simon Horman <hidden>
Date: 2023-05-02 11:56:16
Also in:
linux-sctp, lkml
On Tue, May 02, 2023 at 08:26:30AM +0000, Gavrilov Ilia wrote:
The 'sched' index value must be checked before accessing an element
of the 'sctp_sched_ops' array. Otherwise, it can lead to buffer overflow.
Note that it's harmless since the 'sched' parameter is checked before
calling 'sctp_sched_set_sched'.
Found by InfoTeCS on behalf of Linux Verification Center
(linuxtesting.org) with SVACE.
Fixes: 5bbbbe32a431 ("sctp: introduce stream scheduler foundations")
Signed-off-by: Ilia.Gavrilov <redacted>Reviewed-by: Simon Horman <redacted>
quoted hunk ↗ jump to hunk
--- net/sctp/stream_sched.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)diff --git a/net/sctp/stream_sched.c b/net/sctp/stream_sched.c index 330067002deb..a339917d7197 100644 --- a/net/sctp/stream_sched.c +++ b/net/sctp/stream_sched.c@@ -146,18 +146,19 @@ static void sctp_sched_free_sched(struct sctp_stream *stream) int sctp_sched_set_sched(struct sctp_association *asoc, enum sctp_sched_type sched) { - struct sctp_sched_ops *n = sctp_sched_ops[sched]; + struct sctp_sched_ops *n;
nit: reverse xmas tree - longest line to shortest - for local variable
declarations in networking code.
struct sctp_sched_ops *old = asoc->outqueue.sched; struct sctp_datamsg *msg = NULL; struct sctp_chunk *ch; int i, ret = 0; - if (old == n) - return ret; - if (sched > SCTP_SS_MAX) return -EINVAL; + n = sctp_sched_ops[sched]; + if (old == n) + return ret; + if (old) sctp_sched_free_sched(&asoc->stream); -- 2.30.2