Subject: CVE-2024-49999: afs: Fix the setting of the server responding flag

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

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

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

afs: Fix the setting of the server responding flag

In afs_wait_for_operation(), we set transcribe the call responded flag to
the server record that we used after doing the fileserver iteration loop -
but it's possible to exit the loop having had a response from the server
that we've discarded (e.g. it returned an abort or we started receiving
data, but the call didn't complete).

This means that op->server might be NULL, but we don't check that before
attempting to set the server flag.

The Linux kernel CVE team has assigned CVE-2024-49999 to this issue.

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

	Issue introduced in 6.8 with commit 98f9fda2057b and fixed in 6.10.14 with commit 3d51ab44123f
	Issue introduced in 6.8 with commit 98f9fda2057b and fixed in 6.11.3 with commit 97c953572d98
	Issue introduced in 6.8 with commit 98f9fda2057b and fixed in 6.12-rc2 with commit ff98751bae40

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-2024-49999
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:
	fs/afs/fs_operation.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/3d51ab44123f35dd1d646d99a15ebef10f55e263
	https://git.kernel.org/stable/c/97c953572d98080c5f1486155350bb688041747a
	https://git.kernel.org/stable/c/ff98751bae40faed1ba9c6a7287e84430f7dec64