From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932856AbbEZQNu (ORCPT ); Tue, 26 May 2015 12:13:50 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:33766 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932091AbbEZPmQ (ORCPT ); Tue, 26 May 2015 11:42:16 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Omar Sandoval , Chris Mason , Kamal Mostafa Subject: [PATCH 3.19.y-ckt 07/92] btrfs: unlock i_mutex after attempting to delete subvolume during send Date: Tue, 26 May 2015 08:40:11 -0700 Message-Id: <1432654896-28478-8-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1432654896-28478-1-git-send-email-kamal@canonical.com> References: <1432654896-28478-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.19.8-ckt1 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Omar Sandoval commit 909e26dce3f7600f5e293ac0522c28790a0c8c9c upstream. Whenever the check for a send in progress introduced in commit 521e0546c970 (btrfs: protect snapshots from deleting during send) is hit, we return without unlocking inode->i_mutex. This is easy to see with lockdep enabled: [ +0.000059] ================================================ [ +0.000028] [ BUG: lock held when returning to user space! ] [ +0.000029] 4.0.0-rc5-00096-g3c435c1 #93 Not tainted [ +0.000026] ------------------------------------------------ [ +0.000029] btrfs/211 is leaving the kernel with locks still held! [ +0.000029] 1 lock held by btrfs/211: [ +0.000023] #0: (&type->i_mutex_dir_key){+.+.+.}, at: [] btrfs_ioctl_snap_destroy+0x2df/0x7a0 Make sure we unlock it in the error path. Reviewed-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: Omar Sandoval Signed-off-by: Chris Mason Signed-off-by: Kamal Mostafa --- fs/btrfs/ioctl.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 09a566a..334b0a9 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -2403,7 +2403,7 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file, "Attempt to delete subvolume %llu during send", dest->root_key.objectid); err = -EPERM; - goto out_dput; + goto out_unlock_inode; } d_invalidate(dentry); @@ -2498,6 +2498,7 @@ out_up_write: root_flags & ~BTRFS_ROOT_SUBVOL_DEAD); spin_unlock(&dest->root_item_lock); } +out_unlock_inode: mutex_unlock(&inode->i_mutex); if (!err) { shrink_dcache_sb(root->fs_info->sb); -- 1.9.1