From f084057282bc5f45e5f50a4b226244a30666422d Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Wed, 10 Jan 2024 08:58:26 +1030 Subject: btrfs: defrag: reject unknown flags of btrfs_ioctl_defrag_range_args commit 173431b274a9a54fc10b273b46e67f46bcf62d2e upstream. Add extra sanity check for btrfs_ioctl_defrag_range_args::flags. This is not really to enhance fuzzing tests, but as a preparation for future expansion on btrfs_ioctl_defrag_range_args. In the future we're going to add new members, allowing more fine tuning for btrfs defrag. Without the -ENONOTSUPP error, there would be no way to detect if the kernel supports those new defrag features. CC: stable@vger.kernel.org # 4.14+ Reviewed-by: Filipe Manana Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/ioctl.c | 4 ++++ include/uapi/linux/btrfs.h | 3 +++ 2 files changed, 7 insertions(+) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index c76277ccf03b..11377a94d6f7 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -3037,6 +3037,10 @@ static int btrfs_ioctl_defrag(struct file *file, void __user *argp) kfree(range); goto out; } + if (range->flags & ~BTRFS_DEFRAG_RANGE_FLAGS_SUPP) { + ret = -EOPNOTSUPP; + goto out; + } /* compression requires us to start the IO */ if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { range->flags |= BTRFS_DEFRAG_RANGE_START_IO; diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h index dd7a7b3e53f4..7fdc42645410 100644 --- a/include/uapi/linux/btrfs.h +++ b/include/uapi/linux/btrfs.h @@ -538,6 +538,9 @@ struct btrfs_ioctl_clone_range_args { */ #define BTRFS_DEFRAG_RANGE_COMPRESS 1 #define BTRFS_DEFRAG_RANGE_START_IO 2 +#define BTRFS_DEFRAG_RANGE_FLAGS_SUPP (BTRFS_DEFRAG_RANGE_COMPRESS | \ + BTRFS_DEFRAG_RANGE_START_IO) + struct btrfs_ioctl_defrag_range_args { /* start of the defrag operation */ __u64 start; -- cgit v1.2.3