diff options
| author | Xin Long <lucien.xin@gmail.com> | 2017-12-10 15:40:51 +0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-12-11 14:08:21 -0500 |
| commit | 2342b8d95bcae5946e1b9b8d58645f37500ef2e7 (patch) | |
| tree | a5923dfab3ed4bcc5689218d47543c791d8e7e95 | |
| parent | 8f659a03a0ba9289b9aeb9b4470e6fb263d6f483 (diff) | |
sctp: make sure stream nums can match optlen in sctp_setsockopt_reset_streams
Now in sctp_setsockopt_reset_streams, it only does the check
optlen < sizeof(*params) for optlen. But it's not enough, as
params->srs_number_streams should also match optlen.
If the streams in params->srs_stream_list are less than stream
nums in params->srs_number_streams, later when dereferencing
the stream list, it could cause a slab-out-of-bounds crash, as
reported by syzbot.
This patch is to fix it by also checking the stream numbers in
sctp_setsockopt_reset_streams to make sure at least it's not
greater than the streams in the list.
Fixes: 7f9d68ac944e ("sctp: implement sender-side procedures for SSN Reset Request Parameter")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/sctp/socket.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/net/sctp/socket.c b/net/sctp/socket.c index eb17a911aa29..3253f724a995 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -3891,13 +3891,17 @@ static int sctp_setsockopt_reset_streams(struct sock *sk, struct sctp_association *asoc; int retval = -EINVAL; - if (optlen < sizeof(struct sctp_reset_streams)) + if (optlen < sizeof(*params)) return -EINVAL; params = memdup_user(optval, optlen); if (IS_ERR(params)) return PTR_ERR(params); + if (params->srs_number_streams * sizeof(__u16) > + optlen - sizeof(*params)) + goto out; + asoc = sctp_id2assoc(sk, params->srs_assoc_id); if (!asoc) goto out; |