Subject: CVE-2024-35954: scsi: sg: Avoid sg device teardown race

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

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

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

scsi: sg: Avoid sg device teardown race

sg_remove_sfp_usercontext() must not use sg_device_destroy() after calling
scsi_device_put().

sg_device_destroy() is accessing the parent scsi_device request_queue which
will already be set to NULL when the preceding call to scsi_device_put()
removed the last reference to the parent scsi_device.

The resulting NULL pointer exception will then crash the kernel.

The Linux kernel CVE team has assigned CVE-2024-35954 to this issue.

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

	Issue introduced in 6.5 with commit db59133e9279 and fixed in 6.6.28 with commit 46af9047523e
	Issue introduced in 6.5 with commit db59133e9279 and fixed in 6.8.7 with commit b0d1ebcc1a95
	Issue introduced in 6.5 with commit db59133e9279 and fixed in 6.9 with commit 27f58c04a8f4
	Issue introduced in 6.4.7 with commit 4cc664e59bf2

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-2024-35954
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/scsi/sg.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/46af9047523e2517712ae8e71d984286c626e022
	https://git.kernel.org/stable/c/b0d1ebcc1a9560e494ea9b3ee808540db26c5086
	https://git.kernel.org/stable/c/27f58c04a8f438078583041468ec60597841284d