Re: [PATCH] ext4: validate donor file superblock early in EXT4_IOC_MOVE_EXT

[Theodore Ts'o]

On Mon, 08 Jun 2026 23:25:21 +0800, Yun Zhou wrote:
> Reject the EXT4_IOC_MOVE_EXT ioctl early if the donor file does not
> belong to the same superblock as the original file.  Currently, this
> validation is performed inside ext4_move_extents() by
> mext_check_validity(), but only after lock_two_nondirectories() has
> already acquired the inode locks.  When the donor fd refers to a file
> on a different filesystem (e.g., overlayfs), this late validation
> creates a circular lock dependency:
> 
> [...]

Applied, thanks!

[1/1] ext4: validate donor file superblock early in EXT4_IOC_MOVE_EXT
      commit: c143957520c6c9b5cd72e0de8b52b814f0c576fe

Best regards,
-- 
Theodore Ts'o <tytso@xxxxxxx>