CVE-2026-80945: crypto: iaa - unmap dst before software fallback on decompress

CVE-2026-80945: crypto: iaa - unmap dst before software fallback on decompress

[Greg Kroah-Hartman]

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

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

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

crypto: iaa - unmap dst before software fallback on decompress

On a hardware analytics error, decompress retries through the software
fallback, which writes req->dst with the CPU while it is still mapped
DMA_FROM_DEVICE. With SWIOTLB active the later dma_unmap_sg() copies the
stale bounce buffer over req->dst, corrupting the result.

Unmap before the fallback runs. The async path unmaps inline; the sync
path signals the retry with -EAGAIN so iaa_comp_adecompress() runs the
fallback after unmapping.

The Linux kernel CVE team has assigned CVE-2026-80945 to this issue.


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

	Issue introduced in 6.8 with commit 2ec6761df889fdf896fde761abd447596dd8f8c2 and fixed in 6.18.51 with commit fc933a4a419ba8a75da28666a018602c44846953
	Issue introduced in 6.8 with commit 2ec6761df889fdf896fde761abd447596dd8f8c2 and fixed in 7.2.4 with commit fcd86180ef78b0e41763faef7c6d2de7dfb50c1a
	Issue introduced in 6.8 with commit 2ec6761df889fdf896fde761abd447596dd8f8c2 and fixed in 7.3-rc1 with commit 94a25930477113730372e0fa2985da4c5ac95c9a

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-2026-80945
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/crypto/intel/iaa/iaa_crypto_main.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/fc933a4a419ba8a75da28666a018602c44846953
	https://git.kernel.org/stable/c/fcd86180ef78b0e41763faef7c6d2de7dfb50c1a
	https://git.kernel.org/stable/c/94a25930477113730372e0fa2985da4c5ac95c9a