In the bitmap_ip_uadt function, if ip is greater than ip_to, they are swapped. However, there is no check to see if ip is smaller than map->first, which causes an out-of-bounds vulnerability. Therefore, you need to add a missing bounds check to prevent out-of-bounds. Cc: <stable@xxxxxxxxxxxxxxx> Reported-by: syzbot+58c872f7790a4d2ac951@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 72205fc68bd1 ("netfilter: ipset: bitmap:ip set type support") Signed-off-by: Jeongjun Park <aha310510@xxxxxxxxx> --- net/netfilter/ipset/ip_set_bitmap_ip.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/netfilter/ipset/ip_set_bitmap_ip.c b/net/netfilter/ipset/ip_set_bitmap_ip.c index e4fa00abde6a..705c316b001a 100644 --- a/net/netfilter/ipset/ip_set_bitmap_ip.c +++ b/net/netfilter/ipset/ip_set_bitmap_ip.c @@ -178,7 +178,7 @@ 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) { --