CVE-2026-68327: wan: wanxl: Only reset hardware after BAR mapping

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

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

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

wan: wanxl: Only reset hardware after BAR mapping

wanxl_pci_init_one() stores the freshly allocated card in driver data
before the PLX BAR is mapped.  Several early probe failures then unwind
through wanxl_pci_remove_one(), including failure to allocate the coherent
status area or to restore the DMA mask.

wanxl_pci_remove_one() unconditionally calls wanxl_reset(), and
wanxl_reset() dereferences card->plx.  On those early failures card->plx
is still NULL, so the error path can dereference a NULL MMIO pointer.

Only issue the hardware reset once the BAR mapping exists.  The remaining
cleanup in wanxl_pci_remove_one() already checks whether later resources
were allocated.

This issue was found by a static analysis checker and confirmed by
manual source review.

The Linux kernel CVE team has assigned CVE-2026-68327 to this issue.


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

	Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.6.148 with commit f4834132773f15ffb255127499c8443947fa7d0f
	Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.12.101 with commit b9e2ff70e96acf83693b27987e0390bad9f83efa
	Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.18.42 with commit 59cbe6cfa0fa23c192351cc284e30707309f6741
	Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 7.1.6 with commit 2fe22d58b3797d741570f9873b26653fd511576c
	Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 7.2-rc5 with commit 91957b89da995607cb654b1f9a3c126ddbaee10f

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-2026-68327
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/net/wan/wanxl.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/f4834132773f15ffb255127499c8443947fa7d0f
	https://git.kernel.org/stable/c/b9e2ff70e96acf83693b27987e0390bad9f83efa
	https://git.kernel.org/stable/c/59cbe6cfa0fa23c192351cc284e30707309f6741
	https://git.kernel.org/stable/c/2fe22d58b3797d741570f9873b26653fd511576c
	https://git.kernel.org/stable/c/91957b89da995607cb654b1f9a3c126ddbaee10f