Subject: CVE-2022-48990: drm/amdgpu: fix use-after-free during gpu recovery

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

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

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

drm/amdgpu: fix use-after-free during gpu recovery

[Why]
    [  754.862560] refcount_t: underflow; use-after-free.
    [  754.862898] Call Trace:
    [  754.862903]  <TASK>
    [  754.862913]  amdgpu_job_free_cb+0xc2/0xe1 [amdgpu]
    [  754.863543]  drm_sched_main.cold+0x34/0x39 [amd_sched]

[How]
    The fw_fence may be not init, check whether dma_fence_init
    is performed before job free

The Linux kernel CVE team has assigned CVE-2022-48990 to this issue.

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

	Fixed in 6.0.13 with commit d2a89cd942ed
	Fixed in 6.1 with commit 3cb93f390453

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-2022-48990
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/gpu/drm/amd/amdgpu/amdgpu_job.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/d2a89cd942edd50c1e652004fd64019be78b0a96
	https://git.kernel.org/stable/c/3cb93f390453cde4d6afda1587aaa00e75e09617