Subject: CVE-2024-38545: RDMA/hns: Fix UAF for cq async event

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

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

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

RDMA/hns: Fix UAF for cq async event

The refcount of CQ is not protected by locks. When CQ asynchronous
events and CQ destruction are concurrent, CQ may have been released,
which will cause UAF.

Use the xa_lock() to protect the CQ refcount.

The Linux kernel CVE team has assigned CVE-2024-38545 to this issue.

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

	Issue introduced in 4.9 with commit 9a4435375cd1 and fixed in 5.15.168 with commit 330c825e66ef
	Issue introduced in 4.9 with commit 9a4435375cd1 and fixed in 6.1.93 with commit 763780ef0336
	Issue introduced in 4.9 with commit 9a4435375cd1 and fixed in 6.6.33 with commit 63da190eeb5c
	Issue introduced in 4.9 with commit 9a4435375cd1 and fixed in 6.8.12 with commit 39d26cf46306
	Issue introduced in 4.9 with commit 9a4435375cd1 and fixed in 6.9.3 with commit 37a7559dc135
	Issue introduced in 4.9 with commit 9a4435375cd1 and fixed in 6.10 with commit a942ec2745ca

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-2024-38545
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/infiniband/hw/hns/hns_roce_cq.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/330c825e66ef65278e4ebe57fd49c1d6f3f4e34e
	https://git.kernel.org/stable/c/763780ef0336a973e933e40e919339381732dcaf
	https://git.kernel.org/stable/c/63da190eeb5c9d849b71f457b15b308c94cbaf08
	https://git.kernel.org/stable/c/39d26cf46306bdc7ae809ecfdbfeff5aa1098911
	https://git.kernel.org/stable/c/37a7559dc1358a8d300437e99ed8ecdab0671507
	https://git.kernel.org/stable/c/a942ec2745ca864cd8512142100e4027dc306a42