This is a note to let you know that I've just added the patch titled
netfilter: xt_sctp: validate the flag_info count
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
netfilter-xt_sctp-validate-the-flag_info-count.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From e99476497687ef9e850748fe6d232264f30bc8f9 Mon Sep 17 00:00:00 2001
From: Wander Lairson Costa <wander@xxxxxxxxxx>
Date: Mon, 28 Aug 2023 19:12:55 -0300
Subject: netfilter: xt_sctp: validate the flag_info count
From: Wander Lairson Costa <wander@xxxxxxxxxx>
commit e99476497687ef9e850748fe6d232264f30bc8f9 upstream.
sctp_mt_check doesn't validate the flag_count field. An attacker can
take advantage of that to trigger a OOB read and leak memory
information.
Add the field validation in the checkentry function.
Fixes: 2e4e6a17af35 ("[NETFILTER] x_tables: Abstraction layer for {ip,ip6,arp}_tables")
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: Lucas Leong <wmliang@infosec.exchange>
Signed-off-by: Wander Lairson Costa <wander@xxxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/netfilter/xt_sctp.c | 2 ++
1 file changed, 2 insertions(+)
--- a/net/netfilter/xt_sctp.c
+++ b/net/netfilter/xt_sctp.c
@@ -149,6 +149,8 @@ static int sctp_mt_check(const struct xt
{
const struct xt_sctp_info *info = par->matchinfo;
+ if (info->flag_count > ARRAY_SIZE(info->flag_info))
+ return -EINVAL;
if (info->flags & ~XT_SCTP_VALID_FLAGS)
return -EINVAL;
if (info->invflags & ~XT_SCTP_VALID_FLAGS)
Patches currently in stable-queue which might be from wander@xxxxxxxxxx are
queue-4.19/netfilter-xt_sctp-validate-the-flag_info-count.patch
queue-4.19/netfilter-xt_u32-validate-user-space-input.patch
