4.19-stable review patch. If anyone has any objections, please let me know.
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From: Qu Wenruo wqu@suse.com
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 fdmanana@suse.com Signed-off-by: Qu Wenruo wqu@suse.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/btrfs/ioctl.c | 4 ++++ include/uapi/linux/btrfs.h | 3 +++ 2 files changed, 7 insertions(+)
--- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -3037,6 +3037,10 @@ static int btrfs_ioctl_defrag(struct fil 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; --- 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;