linux-kernel - [PATCH 4.9 54/64] btrfs: prevent to set invalid default subvolid

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue,  3 Oct 2017 14:23:46 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org,
        Satoru Takeuchi <satoru.takeuchi@...il.com>,
        Qu Wenruo <quwenruo.btrfs@....com>,
        David Sterba <dsterba@...e.com>
Subject: [PATCH 4.9 54/64] btrfs: prevent to set invalid default subvolid

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: satoru takeuchi <satoru.takeuchi@...il.com>

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")
Signed-off-by: Satoru Takeuchi <satoru.takeuchi@...il.com>
Reviewed-by: Qu Wenruo <quwenruo.btrfs@....com>
Reviewed-by: David Sterba <dsterba@...e.com>
Signed-off-by: David Sterba <dsterba@...e.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 fs/btrfs/ioctl.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -4082,6 +4082,10 @@ static long btrfs_ioctl_default_subvol(s
 		ret = PTR_ERR(new_root);
 		goto out;
 	}
+	if (!is_fstree(new_root->objectid)) {
+		ret = -ENOENT;
+		goto out;
+	}
 
 	path = btrfs_alloc_path();
 	if (!path) {