ext4: EXT4_IOC_MOVE_EXT: Check for different original and donor inodes first
Move the check to make sure the original and donor inodes are
different earlier, to avoid a potential deadlock by trying to lock the
same inode twice.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c
index 5332fd4..25b6b14 100644
--- a/fs/ext4/move_extent.c
+++ b/fs/ext4/move_extent.c
@@ -1001,14 +1001,6 @@
return -EINVAL;
}
- /* orig and donor should be different file */
- if (orig_inode->i_ino == donor_inode->i_ino) {
- ext4_debug("ext4 move extent: The argument files should not "
- "be same file [ino:orig %lu, donor %lu]\n",
- orig_inode->i_ino, donor_inode->i_ino);
- return -EINVAL;
- }
-
/* Ext4 move extent supports only extent based file */
if (!(EXT4_I(orig_inode)->i_flags & EXT4_EXTENTS_FL)) {
ext4_debug("ext4 move extent: orig file is not extents "
@@ -1232,6 +1224,14 @@
int block_len_in_page;
int uninit;
+ /* orig and donor should be different file */
+ if (orig_inode->i_ino == donor_inode->i_ino) {
+ ext4_debug("ext4 move extent: The argument files should not "
+ "be same file [ino:orig %lu, donor %lu]\n",
+ orig_inode->i_ino, donor_inode->i_ino);
+ return -EINVAL;
+ }
+
/* protect orig and donor against a truncate */
ret1 = mext_inode_double_lock(orig_inode, donor_inode);
if (ret1 < 0)