From patchwork Mon Dec 28 12:45:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 353462 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7745DC4332B for ; Mon, 28 Dec 2020 14:54:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 40CC320897 for ; Mon, 28 Dec 2020 14:54:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391235AbgL1OyV (ORCPT ); Mon, 28 Dec 2020 09:54:21 -0500 Received: from mail.kernel.org ([198.145.29.99]:52136 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2441426AbgL1ORR (ORCPT ); Mon, 28 Dec 2020 09:17:17 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8DCFA207B2; Mon, 28 Dec 2020 14:17:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1609165022; bh=gbZNBjrc2zlFcnWBSOD6PhrMpM+qwB4I32NGCWBDp/U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BkZHEAheBYSkJK+G9njY0SeAyFA2z0aRHGw0aT4Y5grrWIIfGNs/FPf/AMROlqUuN ieiG88BMCYvOMhzYgeSy1y/h6Rjv8a2k9HOMr61peKORZHYDPWiwdlGlynUvXUtBYL 15axxs3OjZAkBkQLjgvm3I8CNjiCvhUvKo543x2k= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Colin Ian King , Jens Axboe , Sasha Levin Subject: [PATCH 5.10 342/717] block/rnbd: fix a null pointer dereference on dev->blk_symlink_name Date: Mon, 28 Dec 2020 13:45:40 +0100 Message-Id: <20201228125037.409803523@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201228125020.963311703@linuxfoundation.org> References: <20201228125020.963311703@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Colin Ian King [ Upstream commit 733c15bd3a944b8eeaacdddf061759b6a83dd3f4 ] Currently in the case where dev->blk_symlink_name fails to be allocates the error return path attempts to set an end-of-string character to the unallocated dev->blk_symlink_name causing a null pointer dereference error. Fix this by returning with an explicity ENOMEM error (which also is missing in the original code as was not initialized). Fixes: 1eb54f8f5dd8 ("block/rnbd: client: sysfs interface functions") Signed-off-by: Colin Ian King Addresses-Coverity: ("Dereference after null check") Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- drivers/block/rnbd/rnbd-clt-sysfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/block/rnbd/rnbd-clt-sysfs.c b/drivers/block/rnbd/rnbd-clt-sysfs.c index b53df40c9a97f..d854f057056bb 100644 --- a/drivers/block/rnbd/rnbd-clt-sysfs.c +++ b/drivers/block/rnbd/rnbd-clt-sysfs.c @@ -494,7 +494,7 @@ static int rnbd_clt_add_dev_symlink(struct rnbd_clt_dev *dev) dev->blk_symlink_name = kzalloc(len, GFP_KERNEL); if (!dev->blk_symlink_name) { rnbd_clt_err(dev, "Failed to allocate memory for blk_symlink_name\n"); - goto out_err; + return -ENOMEM; } ret = rnbd_clt_get_path_name(dev, dev->blk_symlink_name,