CVE-2026-89510: RDMA/cxgb4: Cancel reg_work before freeing device on remove

CVE-2026-89510: RDMA/cxgb4: Cancel reg_work before freeing device on remove

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

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

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

RDMA/cxgb4: Cancel reg_work before freeing device on remove

c4iw_uld_state_change() queues reg_work to register the RDMA device.
c4iw_remove() can free ctx->dev while this work is pending or running,
leaving c4iw_register_device() accessing the freed device.

Cancel reg_work before removing the device.  The registration work can
tear down ctx->dev when registration fails, so do not unregister or
deallocate it again in that case.

This issue was found by an in-house static analysis tool.

The Linux kernel CVE team has assigned CVE-2026-89510 to this issue.


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

	Issue introduced in 4.15 with commit 1c8f1da5d851b92aeb81dbbb9ebd516f6e2588f5 and fixed in 6.12.109 with commit fe9c591026c576d8b1f72aab5e4cd67350530763
	Issue introduced in 4.15 with commit 1c8f1da5d851b92aeb81dbbb9ebd516f6e2588f5 and fixed in 6.18.50 with commit 85f438382a865a4dc4c50e6b884310bb2b60fc4d
	Issue introduced in 4.15 with commit 1c8f1da5d851b92aeb81dbbb9ebd516f6e2588f5 and fixed in 7.2.4 with commit 320e5258a53af0abc5abd9eb01519a48bab2dee8
	Issue introduced in 4.15 with commit 1c8f1da5d851b92aeb81dbbb9ebd516f6e2588f5 and fixed in 7.3-rc1 with commit a7100601aa1a39f799a566acce10db20eaf4b7f2

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-2026-89510
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/cxgb4/device.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/fe9c591026c576d8b1f72aab5e4cd67350530763
	https://git.kernel.org/stable/c/85f438382a865a4dc4c50e6b884310bb2b60fc4d
	https://git.kernel.org/stable/c/320e5258a53af0abc5abd9eb01519a48bab2dee8
	https://git.kernel.org/stable/c/a7100601aa1a39f799a566acce10db20eaf4b7f2