Patch "btrfs: ensure that file descriptor used with subvol ioctls is a dir" has been added to the 4.7-stable tree

This is a note to let you know that I've just added the patch titled

btrfs: ensure that file descriptor used with subvol ioctls is a dir

to the 4.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
btrfs-ensure-that-file-descriptor-used-with-subvol-ioctls-is-a-dir.patch
and it can be found in the queue-4.7 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Jeff Mahoney <[email protected]>
Date: Wed, 21 Sep 2016 08:31:29 -0400
Subject: btrfs: ensure that file descriptor used with subvol ioctls is a dir

From: Jeff Mahoney <[email protected]>

commit 325c50e3cebb9208009083e841550f98a863bfa0 upstream.

If the subvol/snapshot create/destroy ioctls are passed a regular file with execute permissions set, we'll eventually Oops while trying to do inode->i_op->lookup via lookup_one_len.

This patch ensures that the file descriptor refers to a directory.

---
 fs/btrfs/ioctl.c |   12 ++++++++++++
 1 file changed, 12 insertions(+)

@@ -1634,6 +1634,9 @@ static noinline int btrfs_ioctl_snap_cre
 	int namelen;
 	int ret = 0;
 
+	if (!S_ISDIR(file_inode(file)->i_mode))
+		return -ENOTDIR;
+
 	ret = mnt_want_write_file(file);
 	if (ret)
 		goto out;

@@ -1691,6 +1694,9 @@ static noinline int btrfs_ioctl_snap_cre
 	struct btrfs_ioctl_vol_args *vol_args;
 	int ret;
 
+	if (!S_ISDIR(file_inode(file)->i_mode))
+		return -ENOTDIR;
+
 	vol_args = memdup_user(arg, sizeof(*vol_args));
 	if (IS_ERR(vol_args))
 		return PTR_ERR(vol_args);

@@ -1714,6 +1720,9 @@ static noinline int btrfs_ioctl_snap_cre
 	bool readonly = false;
 	struct btrfs_qgroup_inherit *inherit = NULL;
 
+	if (!S_ISDIR(file_inode(file)->i_mode))
+		return -ENOTDIR;
+
 	vol_args = memdup_user(arg, sizeof(*vol_args));
 	if (IS_ERR(vol_args))
 		return PTR_ERR(vol_args);

@@ -2358,6 +2367,9 @@ static noinline int btrfs_ioctl_snap_des
 	int ret;
 	int err = 0;
 
+	if (!S_ISDIR(dir->i_mode))
+		return -ENOTDIR;
+
 	vol_args = memdup_user(arg, sizeof(*vol_args));
 	if (IS_ERR(vol_args))
 		return PTR_ERR(vol_args);

Patches currently in stable-queue which might be from [email protected] are

queue-4.7/btrfs-ensure-that-file-descriptor-used-with-subvol-ioctls-is-a-dir.patch queue-4.7/reiserfs-fix-new_insert_key-may-be-used-uninitialized.patch