Subject: CVE-2021-47523: IB/hfi1: Fix leak of rcvhdrtail_dummy_kvaddr

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

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

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

IB/hfi1: Fix leak of rcvhdrtail_dummy_kvaddr

This buffer is currently allocated in hfi1_init():

	if (reinit)
		ret = init_after_reset(dd);
	else
		ret = loadtime_init(dd);
	if (ret)
		goto done;

	/* allocate dummy tail memory for all receive contexts */
	dd->rcvhdrtail_dummy_kvaddr = dma_alloc_coherent(&dd->pcidev->dev,
							 sizeof(u64),
							 &dd->rcvhdrtail_dummy_dma,
							 GFP_KERNEL);

	if (!dd->rcvhdrtail_dummy_kvaddr) {
		dd_dev_err(dd, "cannot allocate dummy tail memory\n");
		ret = -ENOMEM;
		goto done;
	}

The reinit triggered path will overwrite the old allocation and leak it.

Fix by moving the allocation to hfi1_alloc_devdata() and the deallocation
to hfi1_free_devdata().

The Linux kernel CVE team has assigned CVE-2021-47523 to this issue.

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

	Issue introduced in 4.5 with commit 46b010d3eeb8 and fixed in 5.10.85 with commit 2c08271f4ed0
	Issue introduced in 4.5 with commit 46b010d3eeb8 and fixed in 5.15.8 with commit 834d0fb97864
	Issue introduced in 4.5 with commit 46b010d3eeb8 and fixed in 5.16 with commit 60a8b5a1611b

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-2021-47523
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/hfi1/init.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/2c08271f4ed0e24633b3f81ceff61052b9d45efc
	https://git.kernel.org/stable/c/834d0fb978643eaf09da425de197cc16a7c2761b
	https://git.kernel.org/stable/c/60a8b5a1611b4a26de4839ab9c1fc2a9cf3e17c1