Messages in this thread Patch in this message | | | From | Adam Borowski <> | Date | Wed, 5 Oct 2016 16:38:54 +0200 | Subject | [PATCH resend] vfs: allow FILE_EXTENT_SAME (dedupe_file_range) on a file opened ro |
| |
Instead of checking the mode of the file descriptor, let's check whether it could have been opened rw. This allows fixing intermittent exec failures when deduping a live system: anyone trying to exec a file currently being deduped gets ETXTBSY.
Issuing this ioctl on a ro file was already allowed for root/cap.
Tested on btrfs and not-yet-merged xfs, as only them implement this ioctl.
Signed-off-by: Adam Borowski <kilobyte@angband.pl> Reviewed-by: Mark Fasheh <mfasheh@suse.de> --- fs/read_write.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/read_write.c b/fs/read_write.c index 66215a7..8ea5297 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1741,7 +1741,7 @@ int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same) if (info->reserved) { info->status = -EINVAL; - } else if (!(is_admin || (dst_file->f_mode & FMODE_WRITE))) { + } else if (!(is_admin || !inode_permission(dst, MAY_WRITE))) { info->status = -EINVAL; } else if (file->f_path.mnt != dst_file->f_path.mnt) { info->status = -EXDEV; -- 2.9.3
| |