Subject: CVE-2024-27408: dmaengine: dw-edma: eDMA: Add sync read before starting the DMA transfer in remote setup

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

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

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

dmaengine: dw-edma: eDMA: Add sync read before starting the DMA transfer in remote setup

The Linked list element and pointer are not stored in the same memory as
the eDMA controller register. If the doorbell register is toggled before
the full write of the linked list a race condition error will occur.
In remote setup we can only use a readl to the memory to assure the full
write has occurred.

The Linux kernel CVE team has assigned CVE-2024-27408 to this issue.

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

	Issue introduced in 5.3 with commit 7e4b8a4fbe2c and fixed in 6.6.21 with commit d24fe6d5a1cf
	Issue introduced in 5.3 with commit 7e4b8a4fbe2c and fixed in 6.7.9 with commit f396b4df27cf
	Issue introduced in 5.3 with commit 7e4b8a4fbe2c and fixed in 6.8 with commit bbcc1c83f343

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-2024-27408
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/dma/dw-edma/dw-edma-v0-core.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/d24fe6d5a1cfdddb7a9ef56736ec501c4d0a5fd3
	https://git.kernel.org/stable/c/f396b4df27cfe01a99f4b41f584c49e56477be3a
	https://git.kernel.org/stable/c/bbcc1c83f343e580c3aa1f2a8593343bf7b55bba