CVE-2026-46039: rxgk: Fix potential integer overflow in length check

CVE-2026-46039: rxgk: Fix potential integer overflow in length check

[Greg Kroah-Hartman]

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

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

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

rxgk: Fix potential integer overflow in length check

Fix potential integer overflow in rxgk_extract_token() when checking the
length of the ticket.  Rather than rounding up the value to be tested
(which might overflow), round down the size of the available data.

The Linux kernel CVE team has assigned CVE-2026-46039 to this issue.


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

	Issue introduced in 6.17 with commit 2429a197648178cd4dc930a9d87c13c547460564 and fixed in 6.18.27 with commit 43222ac484f93b3ec2d240a7575e1cedd31f5fa4
	Issue introduced in 6.17 with commit 2429a197648178cd4dc930a9d87c13c547460564 and fixed in 7.0.4 with commit 183d37f12d1c8ed24a5bfc7addad05510da22a94
	Issue introduced in 6.17 with commit 2429a197648178cd4dc930a9d87c13c547460564 and fixed in 7.1-rc1 with commit 6929350080f4da292d111a3b33e53138fee51cec
	Issue introduced in 6.16.9 with commit 71571e187106631a8127f2dde780f35caa358d33

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-2026-46039
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:
	net/rxrpc/rxgk_app.c
	net/rxrpc/rxgk_common.h


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/43222ac484f93b3ec2d240a7575e1cedd31f5fa4
	https://git.kernel.org/stable/c/183d37f12d1c8ed24a5bfc7addad05510da22a94
	https://git.kernel.org/stable/c/6929350080f4da292d111a3b33e53138fee51cec