From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A88B4C433F5 for ; Wed, 13 Apr 2022 06:19:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232065AbiDMGVt (ORCPT ); Wed, 13 Apr 2022 02:21:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48944 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231998AbiDMGVs (ORCPT ); Wed, 13 Apr 2022 02:21:48 -0400 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C61DA35DE8; Tue, 12 Apr 2022 23:19:26 -0700 (PDT) Received: from canpemm500010.china.huawei.com (unknown [172.30.72.56]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4KdXPl1GVnzBsJX; Wed, 13 Apr 2022 14:15:07 +0800 (CST) Received: from huawei.com (10.175.101.6) by canpemm500010.china.huawei.com (7.192.105.118) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Wed, 13 Apr 2022 14:19:23 +0800 From: Liu Jian To: , , , , , , , , , , , , CC: Subject: [PATCH bpf v2 1/2] net: Enlarge offset check value from 0xffff to INT_MAX in bpf_skb_load_bytes Date: Wed, 13 Apr 2022 14:21:30 +0800 Message-ID: <20220413062131.363740-2-liujian56@huawei.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220413062131.363740-1-liujian56@huawei.com> References: <20220413062131.363740-1-liujian56@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.175.101.6] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To canpemm500010.china.huawei.com (7.192.105.118) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org The data length of skb frags + frag_list may be greater than 0xffff, and skb_header_pointer can not handle negative offset and negative len. So here INT_MAX is used to check the validity of offset and len. Add the same change to the related function skb_store_bytes. Fixes: 05c74e5e53f6 ("bpf: add bpf_skb_load_bytes helper") Signed-off-by: Liu Jian Acked-by: Song Liu --- v1->v2: change nothing, only add Acked-by tag net/core/filter.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/core/filter.c b/net/core/filter.c index 64470a727ef7..1571b6bc51ea 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -1687,7 +1687,7 @@ BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset, if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH))) return -EINVAL; - if (unlikely(offset > 0xffff)) + if (unlikely(offset > INT_MAX || len > INT_MAX)) return -EFAULT; if (unlikely(bpf_try_make_writable(skb, offset + len))) return -EFAULT; @@ -1722,7 +1722,7 @@ BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset, { void *ptr; - if (unlikely(offset > 0xffff)) + if (unlikely(offset > INT_MAX || len > INT_MAX)) goto err_clear; ptr = skb_header_pointer(skb, offset, len, to); -- 2.17.1