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 X-Spam-Level: X-Spam-Status: No, score=-9.7 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT autolearn=ham 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 A5E43C43441 for ; Wed, 14 Nov 2018 22:42:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6B3DE2145D for ; Wed, 14 Nov 2018 22:42:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="PMpyZJtQ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6B3DE2145D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387841AbeKOIrY (ORCPT ); Thu, 15 Nov 2018 03:47:24 -0500 Received: from mail.kernel.org ([198.145.29.99]:34716 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728780AbeKOI1W (ORCPT ); Thu, 15 Nov 2018 03:27:22 -0500 Received: from sasha-vm.mshome.net (unknown [64.114.255.114]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D95082252A; Wed, 14 Nov 2018 22:22:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1542234138; bh=1LpCHfmrvSasWtRLwoH0j+BZ/0fFXfEt7fQM2byFWYs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PMpyZJtQeJlPZ5FJzXDlK52JVHJRWYf4CG10w5ZzdxebmCKkGYy8FH8PExhrW0ilq uu3pO9/EYHvvK57tkoHzdkrMxaVrqWTaoj6uXW7zVQ8rWliG4+24UK3VhToQRzEzDD dyASmcDS5iaHFylgQdyfzEvGmrxTUj6KQzWy9oLY= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Luis Henriques , Ilya Dryomov , Sasha Levin Subject: [PATCH AUTOSEL 4.19 45/73] ceph: quota: fix null pointer dereference in quota check Date: Wed, 14 Nov 2018 17:21:39 -0500 Message-Id: <20181114222207.98701-45-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181114222207.98701-1-sashal@kernel.org> References: <20181114222207.98701-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Luis Henriques [ Upstream commit 71f2cc64d027d712f29bf8d09d3e123302d5f245 ] This patch fixes a possible null pointer dereference in check_quota_exceeded, detected by the static checker smatch, with the following warning:    fs/ceph/quota.c:240 check_quota_exceeded()     error: we previously assumed 'realm' could be null (see line 188) Fixes: b7a2921765cf ("ceph: quota: support for ceph.quota.max_files") Reported-by: Dan Carpenter Signed-off-by: Luis Henriques Reviewed-by: "Yan, Zheng" Signed-off-by: Ilya Dryomov Signed-off-by: Sasha Levin --- fs/ceph/quota.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/ceph/quota.c b/fs/ceph/quota.c index 32d4f13784ba..03f4d24db8fe 100644 --- a/fs/ceph/quota.c +++ b/fs/ceph/quota.c @@ -237,7 +237,8 @@ static bool check_quota_exceeded(struct inode *inode, enum quota_check_op op, ceph_put_snap_realm(mdsc, realm); realm = next; } - ceph_put_snap_realm(mdsc, realm); + if (realm) + ceph_put_snap_realm(mdsc, realm); up_read(&mdsc->snap_rwsem); return exceeded; -- 2.17.1