CVE-2026-97488: qnx4: handle set_blocksize failures
In the Linux kernel, the following vulnerability has been resolved:
qnx4: handle setblocksize failures
qnx4 uses bufferheads, which don't handle block size > PAGESIZE well. Without this, mounting will hit the
BUGON(offset >= foliosize(folio));
in foliosetbh on the first breadgfp call.
Affected Software
Event History
Frequently Asked Questions
What conditions are required to trigger the failure?
The issue is triggered when mounting a QNX4 filesystem whose block size is greater than PAGE_SIZE. During the first __bread_gfp call, buffer_heads handling can reach the BUG_ON in folio_set_bh.
What is the practical impact of an affected mount attempt?
An affected mount can hit a kernel BUG_ON, causing the mount operation to fail and potentially resulting in a kernel crash.
Which systems are realistically exposed?
Systems that mount QNX4 filesystems are exposed when the filesystem uses blocks larger than PAGE_SIZE. The provided information does not identify whether QNX4 support is enabled by default.