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=-9.3 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 39BACC43387 for ; Fri, 14 Dec 2018 19:45:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 444DB206C2 for ; Fri, 14 Dec 2018 19:45:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1544816728; bh=KhjkxYEf+JaqGvilFDweB1IRLEDARAUienApVVdYLCc=; h=From:To:Subject:Date:List-ID:From; b=F983ifPoNLzMigzc4CwbO+1CicuJiwsXGZd7JZ/eF3UqxZivpidJAfKZg5P43izcZ YfCrQC5hGO5M5ekyVAfZWQkEcdZrPMLEUKHxmr4SIXdoJyoNtcVpwt2A24ghUEbwhY b59iDHkjuSqR/BScM5/2jZeS1v1GF/pcedEpm6OM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730621AbeLNTp0 (ORCPT ); Fri, 14 Dec 2018 14:45:26 -0500 Received: from mail.kernel.org ([198.145.29.99]:52098 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730123AbeLNTp0 (ORCPT ); Fri, 14 Dec 2018 14:45:26 -0500 Received: from localhost.localdomain (bl8-197-74.dsl.telepac.pt [85.241.197.74]) (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 46C0B206C2 for ; Fri, 14 Dec 2018 19:45:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1544816726; bh=KhjkxYEf+JaqGvilFDweB1IRLEDARAUienApVVdYLCc=; h=From:To:Subject:Date:From; b=h+qZGOURCgtq1J769d/6Rv4Sc2Sm457yjQwmSdo8mSj01YDkruxpVZPOMS/JUxytb 3J/OIV/83OAJWfZaywY3T9DLe5gvZlCzU4op38f4YOaRq14lkjh+ahADp6l/2Xli3l kEd2Y1UAsG/+QVPUPJTkB8xGbZ4pwT2VTw9WmkMQ= From: fdmanana@kernel.org To: linux-btrfs@vger.kernel.org Subject: [PATCH] Btrfs: do not overwrite error return value in the get device stats ioctl Date: Fri, 14 Dec 2018 19:45:22 +0000 Message-Id: <20181214194522.21791-1-fdmanana@kernel.org> X-Mailer: git-send-email 2.11.0 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org From: Filipe Manana If the call to btrfs_get_dev_stats() failed we would overwrite the error returned to user space with -EFAULT if the call to copy_to_user() failed as well. Fix that by calling copy_to_user() only if btrfs_get_dev_stats() returned success. Signed-off-by: Filipe Manana --- fs/btrfs/ioctl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 76848214a39f..0b101df822e9 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -4355,7 +4355,7 @@ static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info, ret = btrfs_get_dev_stats(fs_info, sa); - if (copy_to_user(arg, sa, sizeof(*sa))) + if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa))) ret = -EFAULT; kfree(sa); -- 2.11.0