4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Qu Wenruo <wqu@xxxxxxxx>
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@xxxxxxxxxxxxxxx # 4.14+
Reviewed-by: Filipe Manana <fdmanana@xxxxxxxx>
Signed-off-by: Qu Wenruo <wqu@xxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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;
