From patchwork Thu Sep 4 11:09:15 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Carpenter X-Patchwork-Id: 4843781 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 0D1A89F314 for ; Thu, 4 Sep 2014 11:09:38 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1D23B201EF for ; Thu, 4 Sep 2014 11:09:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EECF9201E4 for ; Thu, 4 Sep 2014 11:09:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753362AbaIDLJc (ORCPT ); Thu, 4 Sep 2014 07:09:32 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:32982 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753041AbaIDLJb (ORCPT ); Thu, 4 Sep 2014 07:09:31 -0400 Received: from ucsinet21.oracle.com (ucsinet21.oracle.com [156.151.31.93]) by userp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id s84B9SDZ012141 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 4 Sep 2014 11:09:29 GMT Received: from userz7021.oracle.com (userz7021.oracle.com [156.151.31.85]) by ucsinet21.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id s84B9Rrc014691 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL); Thu, 4 Sep 2014 11:09:28 GMT Received: from abhmp0016.oracle.com (abhmp0016.oracle.com [141.146.116.22]) by userz7021.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id s84B9Rvo014684; Thu, 4 Sep 2014 11:09:27 GMT Received: from mwanda (/197.157.0.30) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 04 Sep 2014 04:09:26 -0700 Date: Thu, 4 Sep 2014 14:09:15 +0300 From: Dan Carpenter To: Chris Mason Cc: Josef Bacik , linux-btrfs@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [patch] Btrfs: kfree()ing ERR_PTRs Message-ID: <20140904110915.GB21504@mwanda> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: ucsinet21.oracle.com [156.151.31.93] Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-8.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The "inherit" in btrfs_ioctl_snap_create_v2() and "vol_args" in btrfs_ioctl_rm_dev() are ERR_PTRs so we can't call kfree() on them. These kind of bugs are "One Err Bugs" where there is just one error label that does everything. I could set the "inherit = NULL" and keep the single out label but it ends up being more complicated that way. It makes the code simpler to re-order the unwind so it's in the mirror order of the allocation and introduce some new error labels. Signed-off-by: Dan Carpenter --- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index de505d5..741b92b 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -1702,7 +1702,7 @@ static noinline int btrfs_ioctl_snap_create_v2(struct file *file, ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY | BTRFS_SUBVOL_QGROUP_INHERIT)) { ret = -EOPNOTSUPP; - goto out; + goto free_args; } if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) @@ -1712,27 +1712,31 @@ static noinline int btrfs_ioctl_snap_create_v2(struct file *file, if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) { if (vol_args->size > PAGE_CACHE_SIZE) { ret = -EINVAL; - goto out; + goto free_args; } inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size); if (IS_ERR(inherit)) { ret = PTR_ERR(inherit); - goto out; + goto free_args; } } ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, vol_args->fd, subvol, ptr, readonly, inherit); + if (ret) + goto free_inherit; - if (ret == 0 && ptr && - copy_to_user(arg + - offsetof(struct btrfs_ioctl_vol_args_v2, - transid), ptr, sizeof(*ptr))) + if (ptr && copy_to_user(arg + + offsetof(struct btrfs_ioctl_vol_args_v2, + transid), + ptr, sizeof(*ptr))) ret = -EFAULT; -out: - kfree(vol_args); + +free_inherit: kfree(inherit); +free_args: + kfree(vol_args); return ret; } @@ -2649,7 +2653,7 @@ static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg) vol_args = memdup_user(arg, sizeof(*vol_args)); if (IS_ERR(vol_args)) { ret = PTR_ERR(vol_args); - goto out; + goto err_drop; } vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; @@ -2667,6 +2671,7 @@ static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg) out: kfree(vol_args); +err_drop: mnt_drop_write_file(file); return ret; }