Subject: CVE-2024-26789: crypto: arm64/neonbs - fix out-of-bounds access on short input

From: Greg Kroah-Hartman <[email-masked]>

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

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

crypto: arm64/neonbs - fix out-of-bounds access on short input

The bit-sliced implementation of AES-CTR operates on blocks of 128
bytes, and will fall back to the plain NEON version for tail blocks or
inputs that are shorter than 128 bytes to begin with.

It will call straight into the plain NEON asm helper, which performs all
memory accesses in granules of 16 bytes (the size of a NEON register).
For this reason, the associated plain NEON glue code will copy inputs
shorter than 16 bytes into a temporary buffer, given that this is a rare
occurrence and it is not worth the effort to work around this in the asm
code.

The fallback from the bit-sliced NEON version fails to take this into
account, potentially resulting in out-of-bounds accesses. So clone the
same workaround, and use a temp buffer for short in/outputs.

The Linux kernel CVE team has assigned CVE-2024-26789 to this issue.

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

	Issue introduced in 5.18 with commit fc074e130051 and fixed in 6.1.81 with commit 034e2d70b5c7
	Issue introduced in 5.18 with commit fc074e130051 and fixed in 6.6.21 with commit 1291d278b557
	Issue introduced in 5.18 with commit fc074e130051 and fixed in 6.7.9 with commit 9e8ecd4908b5
	Issue introduced in 5.18 with commit fc074e130051 and fixed in 6.8 with commit 1c0cf6d19690

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-2024-26789
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:
	arch/arm64/crypto/aes-neonbs-glue.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/034e2d70b5c7f578200ad09955aeb2aa65d1164a
	https://git.kernel.org/stable/c/1291d278b5574819a7266568ce4c28bce9438705
	https://git.kernel.org/stable/c/9e8ecd4908b53941ab6f0f51584ab80c6c6606c4
	https://git.kernel.org/stable/c/1c0cf6d19690141002889d72622b90fc01562ce4