CVE-2026-80748: mmc: loongson2: Fix sg iteration in data reorder functions

CVE-2026-80748: mmc: loongson2: Fix sg iteration in data reorder functions

[Greg Kroah-Hartman]

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

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

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

mmc: loongson2: Fix sg iteration in data reorder functions

In ls2k0500_mmc_reorder_cmd_data() and ls2k2000_mmc_reorder_cmd_data(),
the for_each_sg() macro already iterates over the scatterlist entries,
with 'sg' pointing to the current entry. However, the code incorrectly
uses '&sg[i]' and 'sg_dma_len(&sg[i])' inside the loop, which treats
'sg' as an array base and indexes it again, leading to access of
wrong sg entries (or out-of-bounds if the list is not an array).

The Linux kernel CVE team has assigned CVE-2026-80748 to this issue.


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

	Issue introduced in 6.17 with commit 2115772014bdac368317e997ed15016cf2792665 and fixed in 6.18.46 with commit 8f7f7a6d5aed8f346a1c936fba02033c73a337dc
	Issue introduced in 6.17 with commit 2115772014bdac368317e997ed15016cf2792665 and fixed in 7.1.10 with commit db368164383c46f256ed8152a41ae9300e615028
	Issue introduced in 6.17 with commit 2115772014bdac368317e997ed15016cf2792665 and fixed in 7.2 with commit 00179ed9fbe07799676e2cb63c4e7f0e7cd80a5c

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-2026-80748
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/mmc/host/loongson2-mmc.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/8f7f7a6d5aed8f346a1c936fba02033c73a337dc
	https://git.kernel.org/stable/c/db368164383c46f256ed8152a41ae9300e615028
	https://git.kernel.org/stable/c/00179ed9fbe07799676e2cb63c4e7f0e7cd80a5c