On 11/14/2018 07:35 PM, fdman...@kernel.org wrote:
From: Filipe Manana <fdman...@suse.com> We were using the path name received from user space without checking that it is null terminated. While btrfs-progs is well behaved and does proper validation and null termination, someone could call the ioctl and pass a non-null terminated patch, leading to buffer overrun problems in the kernel. So just set the last byte of the path to a null character, similar to what we do in other ioctls (add/remove/resize device, snapshot creation, etc). Signed-off-by: Filipe Manana <fdman...@suse.com>
Reviewed-by: Anand Jain <anand.j...@oracle.com> Thanks, Anand
--- fs/btrfs/super.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 6601c9aa5e35..8ad145820ea8 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -2235,6 +2235,7 @@ static long btrfs_control_ioctl(struct file *file, unsigned int cmd, vol = memdup_user((void __user *)arg, sizeof(*vol)); if (IS_ERR(vol)) return PTR_ERR(vol); + vol->name[BTRFS_PATH_NAME_MAX] = '\0';switch (cmd) {case BTRFS_IOC_SCAN_DEV:
