CVE-2026-72089: accel/ivpu: Reject firmware log with size smaller than header

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Greg Kroah-Hartman <gregkh@kernel.org>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

accel/ivpu: Reject firmware log with size smaller than header

fw_log_from_bo() validates the tracing buffer header_size and that the
log fits within the BO, but never checks that log->size is at least
log->header_size. fw_log_print_buffer() then computes:

  u32 data_size = log->size - log->header_size;

which underflows to a near-U32_MAX value when firmware reports a log whose
size is smaller than its header. That huge data_size defeats the
log_start/log_end bounds clamps added by commit dd1311bcf0e6 ("accel/ivpu:
Add bounds checks for firmware log indices"), so fw_log_print_lines() reads
far past the small real data region of the BO. A size of 0 also makes
fw_log_from_bo() advance the offset by 0, causing the callers to loop
forever on the same header.

Reject logs whose size is smaller than the header (which also rejects
size == 0).

The Linux kernel CVE team has assigned CVE-2026-72089 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 6.6 with commit d4e4257afa6ed5205eda993180401fc2c20e4b60 and fixed in 6.6.148 with commit 5592a207e158b738d9c1d27f208dbbea13ae7606
	Issue introduced in 6.6 with commit d4e4257afa6ed5205eda993180401fc2c20e4b60 and fixed in 6.12.97 with commit dc9a1cda2e46d0254730a6f93cfe48532895f33c
	Issue introduced in 6.6 with commit d4e4257afa6ed5205eda993180401fc2c20e4b60 and fixed in 6.18.40 with commit 257321a1c036da417f5d9c47b95c7e58f62bf263
	Issue introduced in 6.6 with commit d4e4257afa6ed5205eda993180401fc2c20e4b60 and fixed in 7.1.5 with commit 6920e62be4c969a68ce4ebc59da68c6cbc9512e5
	Issue introduced in 6.6 with commit d4e4257afa6ed5205eda993180401fc2c20e4b60 and fixed in 7.2-rc4 with commit ddb44baed257560f192b145ed36cf8c0a412de47

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2026-72089
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	drivers/accel/ivpu/ivpu_fw_log.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/5592a207e158b738d9c1d27f208dbbea13ae7606
	https://git.kernel.org/stable/c/dc9a1cda2e46d0254730a6f93cfe48532895f33c
	https://git.kernel.org/stable/c/257321a1c036da417f5d9c47b95c7e58f62bf263
	https://git.kernel.org/stable/c/6920e62be4c969a68ce4ebc59da68c6cbc9512e5
	https://git.kernel.org/stable/c/ddb44baed257560f192b145ed36cf8c0a412de47