From 78004e9a87f240df03e2f73120d291763c32e0a7 Mon Sep 17 00:00:00 2001 From: Ali Ahmet Memis Date: Fri, 21 Aug 2026 01:45:27 +0000 Subject: openrisc: fix arbitrary kernel memory access via or1k_atomic syscall sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user pointers, v1 and v2, and swaps the words they point to in hand-written assembly. l.lwz r29,0(r4) l.lwz r27,0(r5) l.sw 0(r4),r27 l.sw 0(r5),r29 The pointers are not checked with access_ok(). The four memory accesses also have no exception table entries. A caller passes a kernel address as either pointer, and the syscall reads from and writes to it directly. This gives an unprivileged process a kernel read/write primitive. It overwrites kernel data such as the sys_call_table, gaining code execution in kernel context. Check both pointers before entering the critical section. Add fixups for the four memory accesses so faults on valid but unmapped user addresses return -EFAULT. [shorne@gmail.com: fix comment style] Fixes: 9d02a4283e9c ("OpenRISC: Boot code") Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memis Signed-off-by: Stafford Horne --- tools/docs/check-variable-fonts.py | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100755 tools/docs/check-variable-fonts.py (limited to 'tools/docs/check-variable-fonts.py') diff --git a/tools/docs/check-variable-fonts.py b/tools/docs/check-variable-fonts.py new file mode 100755 index 000000000..958d5a745 --- /dev/null +++ b/tools/docs/check-variable-fonts.py @@ -0,0 +1,37 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: GPL-2.0-only +# Copyright (C) Akira Yokosawa, 2024 +# +# Ported to Python by (c) Mauro Carvalho Chehab, 2025 +# +# pylint: disable=C0103 + +""" +Detect problematic Noto CJK variable fonts. + +or more details, see .../tools/lib/python/kdoc/latex_fonts.py. +""" + +import argparse +import sys +import os.path + +src_dir = os.path.dirname(os.path.realpath(__file__)) +sys.path.insert(0, os.path.join(src_dir, '../lib/python')) + +from kdoc.latex_fonts import LatexFontChecker + +checker = LatexFontChecker() + +parser=argparse.ArgumentParser(description=checker.description(), + formatter_class=argparse.RawTextHelpFormatter) +parser.add_argument("--deny-vf", + help="XDG_CONFIG_HOME dir containing fontconfig/fonts.conf file") + +args=parser.parse_args() + +msg = LatexFontChecker(args.deny_vf).check() +if msg: + print(msg) + +sys.exit(1) -- cgit v1.3.1