From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934598AbdKAVez (ORCPT ); Wed, 1 Nov 2017 17:34:55 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:35521 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933951AbdKAV3p (ORCPT ); Wed, 1 Nov 2017 17:29:45 -0400 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux@roeck-us.net Cc: satoru takeuchi , David Sterba , Willy Tarreau Subject: [PATCH 3.10 132/139] btrfs: prevent to set invalid default subvolid Date: Wed, 1 Nov 2017 22:26:57 +0100 Message-Id: <1509571624-5001-33-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1509571624-5001-1-git-send-email-w@1wt.eu> References: <1509571159-4405-1-git-send-email-w@1wt.eu> <1509571624-5001-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: satoru takeuchi commit 6d6d282932d1a609e60dc4467677e0e863682f57 upstream. `btrfs sub set-default` succeeds to set an ID which isn't corresponding to any fs/file tree. If such the bad ID is set to a filesystem, we can't mount this filesystem without specifying `subvol` or `subvolid` mount options. Fixes: 6ef5ed0d386b ("Btrfs: add ioctl and incompat flag to set the default mount subvol") Cc: Signed-off-by: Satoru Takeuchi Reviewed-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Willy Tarreau --- fs/btrfs/ioctl.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 296cc1b..7831e68 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -2974,6 +2974,10 @@ static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp) ret = PTR_ERR(new_root); goto out; } + if (!is_fstree(new_root->objectid)) { + ret = -ENOENT; + goto out; + } if (btrfs_root_refs(&new_root->root_item) == 0) { ret = -ENOENT; -- 2.8.0.rc2.1.gbe9624a