CVE-2026-97490: affs: handle set_blocksize failures
In the Linux kernel, the following vulnerability has been resolved:
affs: handle setblocksize failures
affs uses bufferheads, which don't handle block size > PAGESIZE well. Without this, mounting we will hit the
BUGON(offset >= foliosize(folio));
in foliosetbh on the first breadgfp call.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Compensating control
In affs, handle set_blocksize failures in folio_set_bh during the first __bread_gfp call to prevent the BUG_ON(offset >= folio_size(folio)) condition.
Event History
Frequently Asked Questions
Which systems are exposed to this issue?
Linux systems that mount an AFFS filesystem with a block size larger than PAGE_SIZE are exposed. The issue is specific to AFFS use of buffer_heads with oversized blocks.
What is the observable failure when the issue is triggered?
The mount operation can hit BUG_ON(offset >= folio_size(folio)) in folio_set_bh during the first __bread_gfp call.