[PATCH] sctp: account stream padding length for reconf chunk

[Greg KH <gregkh@linuxfoundation.org>]

From: Eiichi Tsukata <eiichi.tsukata@nutanix.com>

"stream_len" is not always multiple of 4. Account padding length
which can be added in sctp_addto_chunk() for reconf chunk.

Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: linux-sctp@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Fixes: cc16f00f6529 ("sctp: add support for generating stream reconf ssn reset request chunk")
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Eiichi Tsukata <eiichi.tsukata@nutanix.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/sctp/sm_make_chunk.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index b8fa8f1a7277..f7a1072a2a2a 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -3694,8 +3694,8 @@ struct sctp_chunk *sctp_make_strreset_req(
 	struct sctp_chunk *retval;
 	__u16 outlen, inlen;
 
-	outlen = (sizeof(outreq) + stream_len) * out;
-	inlen = (sizeof(inreq) + stream_len) * in;
+	outlen = (sizeof(outreq) + SCTP_PAD4(stream_len)) * out;
+	inlen = (sizeof(inreq) + SCTP_PAD4(stream_len)) * in;
 
 	retval = sctp_make_reconf(asoc, outlen + inlen);
 	if (!retval)
-- 
2.33.0