CVE-2026-80707: can: j1939: transport: j1939_session_fresh_new(): initialize receive buffer

CVE-2026-80707: can: j1939: transport: j1939_session_fresh_new(): initialize receive buffer

[Greg Kroah-Hartman]

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

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

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

can: j1939: transport: j1939_session_fresh_new(): initialize receive buffer

Zero the allocated buffer in j1939_session_fresh_new() to ensure it
contains no residual data.

While there is a potential performance impact if users allocate maximum
sized ETP buffers, most real-world use cases are not noticeably affected
since the maximum known buffer size is typically around 65K.

[mkl: add Message-ID]

The Linux kernel CVE team has assigned CVE-2026-80707 to this issue.


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

	Issue introduced in 5.4 with commit 9d71dd0c70099914fcd063135da3c580865e924c and fixed in 5.10.265 with commit 348818277a3646d5b9fa60c9d20c00dc4bc86832
	Issue introduced in 5.4 with commit 9d71dd0c70099914fcd063135da3c580865e924c and fixed in 5.15.216 with commit f3e120a34b336079479fa10f706f0636eaa6e751
	Issue introduced in 5.4 with commit 9d71dd0c70099914fcd063135da3c580865e924c and fixed in 6.1.183 with commit bbfa49d1e287de44994955b44d19281be3195b44
	Issue introduced in 5.4 with commit 9d71dd0c70099914fcd063135da3c580865e924c and fixed in 6.6.151 with commit 194d67e92197eb820f4c2c6605d9721333b3eba0
	Issue introduced in 5.4 with commit 9d71dd0c70099914fcd063135da3c580865e924c and fixed in 6.12.103 with commit 038bad8e16c2e28acf31f0b527a816fb23a57269
	Issue introduced in 5.4 with commit 9d71dd0c70099914fcd063135da3c580865e924c and fixed in 6.18.44 with commit 8604a3b81b9d0ceaf04fee5f52e701f623a179f9
	Issue introduced in 5.4 with commit 9d71dd0c70099914fcd063135da3c580865e924c and fixed in 7.1.8 with commit d5b3613c7d69d8dcb4dd6704f1f463198ce9f6cf
	Issue introduced in 5.4 with commit 9d71dd0c70099914fcd063135da3c580865e924c and fixed in 7.2 with commit eb96c58907922546e415e545fe9a14ea63b02719

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-2026-80707
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/can/j1939/transport.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/348818277a3646d5b9fa60c9d20c00dc4bc86832
	https://git.kernel.org/stable/c/f3e120a34b336079479fa10f706f0636eaa6e751
	https://git.kernel.org/stable/c/bbfa49d1e287de44994955b44d19281be3195b44
	https://git.kernel.org/stable/c/194d67e92197eb820f4c2c6605d9721333b3eba0
	https://git.kernel.org/stable/c/038bad8e16c2e28acf31f0b527a816fb23a57269
	https://git.kernel.org/stable/c/8604a3b81b9d0ceaf04fee5f52e701f623a179f9
	https://git.kernel.org/stable/c/d5b3613c7d69d8dcb4dd6704f1f463198ce9f6cf
	https://git.kernel.org/stable/c/eb96c58907922546e415e545fe9a14ea63b02719