Messages in this thread Patch in this message | | | From | Jiri Slaby <> | Subject | [PATCH 3.12 22/84] btrfs: ensure that file descriptor used with subvol ioctls is a dir | Date | Mon, 17 Oct 2016 09:51:09 +0200 |
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From: Jeff Mahoney <jeffm@suse.com>
3.12-stable review patch. If anyone has any objections, please let me know.
===============
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.
Fixes: cb8e70901d (Btrfs: Fix subvolume creation locking rules) Fixes: 76dda93c6a (Btrfs: add snapshot/subvolume destroy ioctl) Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> --- fs/btrfs/ioctl.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 5f597cf570be..0dd3a574ab10 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -1516,6 +1516,9 @@ static noinline int btrfs_ioctl_snap_create_transid(struct file *file, 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; @@ -1573,6 +1576,9 @@ static noinline int btrfs_ioctl_snap_create(struct file *file, 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); @@ -1596,6 +1602,9 @@ static noinline int btrfs_ioctl_snap_create_v2(struct file *file, 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); @@ -2118,6 +2127,9 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file, 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); -- 2.10.1
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