Subject: CVE-2021-47420: drm/amdkfd: fix a potential ttm->sg memory leak

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

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

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

drm/amdkfd: fix a potential ttm->sg memory leak

Memory is allocated for ttm->sg by kmalloc in kfd_mem_dmamap_userptr,
but isn't freed by kfree in kfd_mem_dmaunmap_userptr. Free it!

The Linux kernel CVE team has assigned CVE-2021-47420 to this issue.

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

	Issue introduced in 5.14 with commit 264fb4d332f5 and fixed in 5.14.12 with commit 7e5ce6029b62
	Issue introduced in 5.14 with commit 264fb4d332f5 and fixed in 5.15 with commit b072ef1215ac

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-2021-47420
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_amdkfd_gpuvm.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/7e5ce6029b627efb4a004746cfdc1eeff850e6eb
	https://git.kernel.org/stable/c/b072ef1215aca33186e3a10109e872e528a9e516