linux-cve-announce - CVE-2025-39716: parisc: Revise __get

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <2025090551-CVE-2025-39716-7e3c@gregkh>
Date: Fri,  5 Sep 2025 19:21:29 +0200
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-cve-announce@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...nel.org>
Subject: CVE-2025-39716: parisc: Revise __get_user() to probe user read access

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

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

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

parisc: Revise __get_user() to probe user read access

Because of the way read access support is implemented, read access
interruptions are only triggered at privilege levels 2 and 3. The
kernel executes at privilege level 0, so __get_user() never triggers
a read access interruption (code 26). Thus, it is currently possible
for user code to access a read protected address via a system call.

Fix this by probing read access rights at privilege level 3 (PRIV_USER)
and setting __gu_err to -EFAULT (-14) if access isn't allowed.

Note the cmpiclr instruction does a 32-bit compare because COND macro
doesn't work inside asm.

The Linux kernel CVE team has assigned CVE-2025-39716 to this issue.


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

	Fixed in 6.1.149 with commit 28a9b71671fb4a2993ef85b8ef6f117ea63894fe
	Fixed in 6.6.103 with commit 4c981077255acc2ed5b3df6e8dd0125c81b626a9
	Fixed in 6.12.44 with commit f410ef9a032caf98117256b22139c31342d7bb06
	Fixed in 6.16.4 with commit 741b163e440683195b8fd4fc8495fcd0105c6ab7
	Fixed in 6.17-rc1 with commit 89f686a0fb6e473a876a9a60a13aec67a62b9a7e

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-2025-39716
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:
	arch/parisc/include/asm/uaccess.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/28a9b71671fb4a2993ef85b8ef6f117ea63894fe
	https://git.kernel.org/stable/c/4c981077255acc2ed5b3df6e8dd0125c81b626a9
	https://git.kernel.org/stable/c/f410ef9a032caf98117256b22139c31342d7bb06
	https://git.kernel.org/stable/c/741b163e440683195b8fd4fc8495fcd0105c6ab7
	https://git.kernel.org/stable/c/89f686a0fb6e473a876a9a60a13aec67a62b9a7e