From patchwork Thu Oct 13 07:10:35 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "yebin (H)" X-Patchwork-Id: 13005680 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 3A54EC4332F for ; Thu, 13 Oct 2022 06:48:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229599AbiJMGsh (ORCPT ); Thu, 13 Oct 2022 02:48:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44668 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229820AbiJMGsc (ORCPT ); Thu, 13 Oct 2022 02:48:32 -0400 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D20D1141129; Wed, 12 Oct 2022 23:48:29 -0700 (PDT) Received: from canpemm500010.china.huawei.com (unknown [172.30.72.57]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4Mp0NQ6kN5z1P7BC; Thu, 13 Oct 2022 14:43:50 +0800 (CST) Received: from huawei.com (10.175.127.227) 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 15.1.2375.31; Thu, 13 Oct 2022 14:48:26 +0800 From: Ye Bin To: , , , , CC: , , Subject: [PATCH -next 2/2] smb3: fix potential wild-ptr-deref in 'smb3_free_compound_rqst' Date: Thu, 13 Oct 2022 15:10:35 +0800 Message-ID: <20221013071035.2890124-3-yebin10@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20221013071035.2890124-1-yebin10@huawei.com> References: <20221013071035.2890124-1-yebin10@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To canpemm500010.china.huawei.com (7.192.105.118) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org As 'smb3_init_transform_rq' first set 'new_rq[i].rq_npages', then allocate page, if allocate page failed will call 'smb3_free_compound_rqst' to free page. However, there may only allocate part of 'rq_npages' pages which will lead to wild-ptr-deref when free pages. To solve above issue just increase 'new_rq[i].rq_npages' after allocate page success. Signed-off-by: Ye Bin --- fs/cifs/smb2ops.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 180f0260cbc4..a1b47ce4ea15 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -4467,7 +4467,6 @@ smb3_init_transform_rq(struct TCP_Server_Info *server, int num_rqst, goto err_free; nrq->rq_pages = pages; - nrq->rq_npages = npages; nrq->rq_offset = orq->rq_offset; nrq->rq_pagesz = orq->rq_pagesz; nrq->rq_tailsz = orq->rq_tailsz; @@ -4480,6 +4479,7 @@ smb3_init_transform_rq(struct TCP_Server_Info *server, int num_rqst, pages[j] = alloc_page(GFP_KERNEL|__GFP_HIGHMEM); if (!pages[j]) goto err_free; + nrq->rq_npages++; } /* copy pages form the old */