diff options
| -rw-r--r-- | fs/btrfs/ioctl.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index b3d249d6eba..028a4b8c12c 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -2333,14 +2333,21 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, if (type == BTRFS_FILE_EXTENT_REG || type == BTRFS_FILE_EXTENT_PREALLOC) { + /* + * a | --- range to clone ---| b + * | ------------- extent ------------- | + */ + + /* substract range b */ + if (key.offset + datal > off + len) + datal = off + len - key.offset; + + /* substract range a */ if (off > key.offset) { datao += off - key.offset; datal -= off - key.offset; } - if (key.offset + datal > off + len) - datal = off + len - key.offset; - ret = btrfs_drop_extents(trans, inode, new_key.offset, new_key.offset + datal, |