[SRU][N/J/F][PATCH 1/1] netfilter: ipset: add missing range check in bitmap_ip_uadt

[Ian Whitfield]

From: Jeongjun Park <aha310510 at gmail.com>

When tb[IPSET_ATTR_IP_TO] is not present but tb[IPSET_ATTR_CIDR] exists,
the values of ip and ip_to are slightly swapped. Therefore, the range check
for ip should be done later, but this part is missing and it seems that the
vulnerability occurs.

So we should add missing range checks and remove unnecessary range checks.

Cc: <stable at vger.kernel.org>
Reported-by: syzbot+58c872f7790a4d2ac951 at syzkaller.appspotmail.com
Fixes: 72205fc68bd1 ("netfilter: ipset: bitmap:ip set type support")
Signed-off-by: Jeongjun Park <aha310510 at gmail.com>
Acked-by: Jozsef Kadlecsik <kadlec at blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo at netfilter.org>
(cherry picked from commit 35f56c554eb1b56b77b3cf197a6b00922d49033d)
CVE-2024-53141
Signed-off-by: Ian Whitfield <ian.whitfield at canonical.com>
---
 net/netfilter/ipset/ip_set_bitmap_ip.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/net/netfilter/ipset/ip_set_bitmap_ip.c b/net/netfilter/ipset/ip_set_bitmap_ip.c
index e4fa00abde6a..5988b9bb9029 100644
--- a/net/netfilter/ipset/ip_set_bitmap_ip.c
+++ b/net/netfilter/ipset/ip_set_bitmap_ip.c
@@ -163,11 +163,8 @@ bitmap_ip_uadt(struct ip_set *set, struct nlattr *tb[],
 		ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &ip_to);
 		if (ret)
 			return ret;
-		if (ip > ip_to) {
+		if (ip > ip_to)
 			swap(ip, ip_to);
-			if (ip < map->first_ip)
-				return -IPSET_ERR_BITMAP_RANGE;
-		}
 	} else if (tb[IPSET_ATTR_CIDR]) {
 		u8 cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
 
@@ -178,7 +175,7 @@ bitmap_ip_uadt(struct ip_set *set, struct nlattr *tb[],
 		ip_to = ip;
 	}
 
-	if (ip_to > map->last_ip)
+	if (ip < map->first_ip || ip_to > map->last_ip)
 		return -IPSET_ERR_BITMAP_RANGE;
 
 	for (; !before(ip_to, ip); ip += map->hosts) {
-- 
2.43.0