From patchwork Mon Apr 11 13:02:54 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liu Jian X-Patchwork-Id: 12809086 X-Patchwork-Delegate: bpf@iogearbox.net 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 01926C4332F for ; Mon, 11 Apr 2022 13:00:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244175AbiDKNDA (ORCPT ); Mon, 11 Apr 2022 09:03:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54864 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231367AbiDKNDA (ORCPT ); Mon, 11 Apr 2022 09:03:00 -0400 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E04401A059; Mon, 11 Apr 2022 06:00:45 -0700 (PDT) Received: from canpemm500010.china.huawei.com (unknown [172.30.72.57]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4KcTV2301Zz1HBjN; Mon, 11 Apr 2022 21:00:10 +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; Mon, 11 Apr 2022 21:00:42 +0800 From: Liu Jian To: , , , , , , , , , , , , CC: Subject: [PATCH bpf 1/2] net: Enlarge offset check value from 0xffff to INT_MAX in bpf_skb_load_bytes Date: Mon, 11 Apr 2022 21:02:54 +0800 Message-ID: <20220411130255.385520-2-liujian56@huawei.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220411130255.385520-1-liujian56@huawei.com> References: <20220411130255.385520-1-liujian56@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.101.6] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To canpemm500010.china.huawei.com (7.192.105.118) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net 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 --- 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 a7044e98765e..b0a3b6489701 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);