diff mbox series

[SRU,F/J/L,1/1] netfilter: xt_sctp: validate the flag_info count

Message ID 20231026141524.257138-2-magali.lemes@canonical.com
State New
Headers show
Series CVE-2023-39193 | expand

Commit Message

Magali Lemes Oct. 26, 2023, 2:15 p.m. UTC 
From: Wander Lairson Costa <wander@redhat.com>

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@vger.kernel.org
Reported-by: Lucas Leong <wmliang@infosec.exchange>
Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
(cherry picked from commit e99476497687ef9e850748fe6d232264f30bc8f9)
CVE-2023-39193
Signed-off-by: Magali Lemes <magali.lemes@canonical.com>
---
 net/netfilter/xt_sctp.c | 2 ++
 1 file changed, 2 insertions(+)
diff mbox series

Patch

diff --git a/net/netfilter/xt_sctp.c b/net/netfilter/xt_sctp.c
index 680015ba7cb6..d4bf089c9e3f 100644
--- a/net/netfilter/xt_sctp.c
+++ b/net/netfilter/xt_sctp.c
@@ -150,6 +150,8 @@  static int sctp_mt_check(const struct xt_mtchk_param *par)
 {
 	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)