Unverified Commit 43085dbc authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
Browse files

!6918 bpf: Fix hashtab overflow check on 32-bit arches 

Merge Pull Request from: @ci-robot 
 
PR sync from: g30012805 <guomengqi3@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/UWLBM5ZYP3AMNYINOP6XA3B6IFXXQGV2/ 
 
https://gitee.com/src-openeuler/kernel/issues/I9HK6X 
 
Link:https://gitee.com/openeuler/kernel/pulls/6918

 

Reviewed-by: default avatarXu Kuohai <xukuohai@huawei.com>
Signed-off-by: default avatarJialin Zhang <zhangjialin11@huawei.com>
parents 24c87f13 ac521bb5

kernel/bpf/hashtab.c

+9 −5
Original line number Diff line number Diff line
@@ -443,7 +443,13 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr) 
							  num_possible_cpus());

	}



	/* hash table size must be power of 2 */

	/* hash table size must be power of 2; roundup_pow_of_two() can overflow

	 * into UB on 32-bit arches, so check that first

	 */

	err = -E2BIG;

	if (htab->map.max_entries > 1UL << 31)

		goto free_htab;



	htab->n_buckets = roundup_pow_of_two(htab->map.max_entries);



	htab->elem_size = sizeof(struct htab_elem) +
@@ -453,10 +459,8 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr) 
	else

		htab->elem_size += round_up(htab->map.value_size, 8);



	err = -E2BIG;

	/* prevent zero size kmalloc and check for u32 overflow */

	if (htab->n_buckets == 0 ||

	    htab->n_buckets > U32_MAX / sizeof(struct bucket))

	/* check for u32 overflow */

	if (htab->n_buckets > U32_MAX / sizeof(struct bucket))

		goto free_htab;



	cost = (u64) htab->n_buckets * sizeof(struct bucket) +