Subject: CVE-2023-52464: EDAC/thunderx: Fix possible out-of-bounds string access

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

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

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

EDAC/thunderx: Fix possible out-of-bounds string access

Enabling -Wstringop-overflow globally exposes a warning for a common bug
in the usage of strncat():

  drivers/edac/thunderx_edac.c: In function 'thunderx_ocx_com_threaded_isr':
  drivers/edac/thunderx_edac.c:1136:17: error: 'strncat' specified bound 1024 equals destination size [-Werror=stringop-overflow=]
   1136 |                 strncat(msg, other, OCX_MESSAGE_SIZE);
        |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   ...
   1145 |                                 strncat(msg, other, OCX_MESSAGE_SIZE);
   ...
   1150 |                                 strncat(msg, other, OCX_MESSAGE_SIZE);

   ...

Apparently the author of this driver expected strncat() to behave the
way that strlcat() does, which uses the size of the destination buffer
as its third argument rather than the length of the source buffer. The
result is that there is no check on the size of the allocated buffer.

Change it to strlcat().

  [ bp: Trim compiler output, fixup commit message. ]

The Linux kernel CVE team has assigned CVE-2023-52464 to this issue.

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

	Issue introduced in 4.12 with commit 41003396f932 and fixed in 4.19.306 with commit 71c17ee02538
	Issue introduced in 4.12 with commit 41003396f932 and fixed in 5.4.268 with commit 5da3b6e7196f
	Issue introduced in 4.12 with commit 41003396f932 and fixed in 5.10.209 with commit 6aa7865ba7ff
	Issue introduced in 4.12 with commit 41003396f932 and fixed in 5.15.148 with commit 700cf4bead80
	Issue introduced in 4.12 with commit 41003396f932 and fixed in 6.1.75 with commit 9dbac9fdae6e
	Issue introduced in 4.12 with commit 41003396f932 and fixed in 6.6.14 with commit e1c865112415
	Issue introduced in 4.12 with commit 41003396f932 and fixed in 6.7.2 with commit 426fae93c01d
	Issue introduced in 4.12 with commit 41003396f932 and fixed in 6.8 with commit 475c58e1a471

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-2023-52464
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/edac/thunderx_edac.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/71c17ee02538802ceafc830f0736aa35b564e601
	https://git.kernel.org/stable/c/5da3b6e7196f0b4f3728e4e25eb20233a9ddfaf6
	https://git.kernel.org/stable/c/6aa7865ba7ff7f0ede0035180fb3b9400ceb405a
	https://git.kernel.org/stable/c/700cf4bead80fac994dcc43ae1ca5d86d8959b21
	https://git.kernel.org/stable/c/9dbac9fdae6e3b411fc4c3fca3bf48f70609c398
	https://git.kernel.org/stable/c/e1c86511241588efffaa49556196f09a498d5057
	https://git.kernel.org/stable/c/426fae93c01dffa379225eb2bd4d3cdc42c6eec5
	https://git.kernel.org/stable/c/475c58e1a471e9b873e3e39958c64a2d278275c8