From 07beceb3e133152d1a36f38c94baea18e77fa1d0 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Wed, 10 Jan 2024 08:58:26 +1030 Subject: [PATCH] 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 233e465647fd..8627c43c812a 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -3183,6 +3183,10 @@ static int btrfs_ioctl_defrag(struct file *file, void __user *argp) ret = -EFAULT; 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 5f4513f2d41d..4693b6ba30a1 100644 --- a/include/uapi/linux/btrfs.h +++ b/include/uapi/linux/btrfs.h @@ -578,6 +578,9 @@ 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;