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>
This commit is contained in:
Theodore Ts'o 2009-09-28 15:58:29 -04:00
parent 8d5d02e6b1
commit f3ce8064b3

View file

@ -1001,14 +1001,6 @@ mext_check_arguments(struct inode *orig_inode,
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 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp,
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)