github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-09-22 04:34:03 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

mptcp: options: reset DSS fields in case of unexpected size

Browse Source 
A remote peer could send a malformed DSS with a wrong size, followed by
another DSS or MPC + Data. In this case, the first suboption will be
ignored, but leaving some fields written, which could lead to
inconsistency or access uninitialized data.

Explicitly reset the fields that could have been modified in case of
unexpected size.

Link: https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20260728-net-mptcp-misc-fixes-7-2-rc6-v1-0-f7e2d229159d%40kernel.org?part=1
Fixes: 648ef4b886 ("mptcp: Implement MPTCP receive path")
Cc: stable@vger.kernel.org
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260803-net-mptcp-misc-fixes-7-2-rc6-v2-1-b8f496d71664@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Matthieu Baerts (NGI0) 2026-08-03 18:16:33 +02:00 committed by Jakub Kicinski
parent fde39b8a52
commit 35772b4981
1 changed files with 7 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
net/mptcp/options.c
View File

@ -188,8 +188,14 @@ static void mptcp_parse_option(const struct sk_buff *skb,
* RFC 8684 Section 3.3.0 checks later in subflow_data_ready
*/
if (opsize != expected_opsize &&
opsize != expected_opsize + TCPOLEN_MPTCP_DSS_CHECKSUM)
opsize != expected_opsize + TCPOLEN_MPTCP_DSS_CHECKSUM) {
mp_opt->dsn64 = 0;
mp_opt->use_map = 0;
mp_opt->ack64 = 0;
mp_opt->use_ack = 0;
mp_opt->data_fin = 0;
break;
}
mp_opt->suboptions |= OPTION_MPTCP_DSS;
if (mp_opt->use_ack) {