In the Linux kernel, the following vulnerability has been resolved: dm-integrity: validate the superblock on resume dm_integrity_resume() re-reads… (CVE-2026-99086)

The dm-integrity module in the Linux kernel re-reads the superblock on resume via dm_integrity_resume() but does not validate the superblock contents against the originally validated version. Since the user can modify the superblock on the underlying device while the dm-integrity device is suspended, this can cause inconsistencies. Specifically, if the log2_sectors_per_block field increases, the journal entry index calculation can exceed the journal's bounds, causing a 512-byte write through lowmem_page_address(NULL), effectively a kernel memory corruption. The resolution is to snapshot the validated superblock during the constructor and refuse to resume if any on-disk geometry fields have changed.

This vulnerability can lead to kernel memory corruption due to out-of-bounds writes when resuming a dm-integrity device with a modified superblock. Such corruption could potentially cause system instability or crashes. No known exploits in the wild have been reported.

A fix has been implemented that snapshots the validated superblock during construction and prevents resuming if critical superblock fields have changed. Users should apply the official Linux kernel updates that include this fix. Since this is not a cloud service, remediation depends on applying kernel patches from the vendor or distribution.