netfilter: ipset: Fix overflow before widen in the bitmap_ip_create() function.

stable inclusion
from stable-v5.10.164
commit 4e6a70fd840400e3a2e784a6673968a3eb2431c0
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7T7G4

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=4e6a70fd840400e3a2e784a6673968a3eb2431c0

--------------------------------

commit 9ea4b476 upstream.

When first_ip is 0, last_ip is 0xFFFFFFFF, and netmask is 31, the value of
an arithmetic expression 2 << (netmask - mask_bits - 1) is subject
to overflow due to a failure casting operands to a larger data type
before performing the arithmetic.

Note that it's harmless since the value will be checked at the next step.

Found by InfoTeCS on behalf of Linux Verification Center
(linuxtesting.org) with SVACE.

Fixes: b9fed748 ("netfilter: ipset: Check and reject crazy /0 input parameters")
Signed-off-by: NIlia.Gavrilov <Ilia.Gavrilov@infotecs.ru>
Reviewed-by: NSimon Horman <simon.horman@corigine.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Nsanglipeng <sanglipeng1@jd.com>

net/netfilter/ipset/ip_set_bitmap_ip.c

@@ -308,8 +308,8 @@ bitmap_ip_create(struct net *net, struct ip_set *set, struct nlattr *tb[],
 			return -IPSET_ERR_BITMAP_RANGE;
 
 		pr_debug("mask_bits %u, netmask %u\n", mask_bits, netmask);
-		hosts = 2 << (32 - netmask - 1);
-		elements = 2 << (netmask - mask_bits - 1);
+		hosts = 2U << (32 - netmask - 1);
+		elements = 2UL << (netmask - mask_bits - 1);
 	}
 	if (elements > IPSET_BITMAP_MAX_RANGE + 1)
 		return -IPSET_ERR_BITMAP_RANGE_SIZE;