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 --- scripts/install.sh | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100755 scripts/install.sh (limited to 'scripts/install.sh') diff --git a/scripts/install.sh b/scripts/install.sh new file mode 100755 index 000000000..05d62ac51 --- /dev/null +++ b/scripts/install.sh @@ -0,0 +1,44 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0-only +# +# Copyright (C) 1995 by Linus Torvalds +# +# Adapted from code in arch/i386/boot/Makefile by H. Peter Anvin +# Common code factored out by Masahiro Yamada + +set -e + +# Make sure the files actually exist +for file in "${KBUILD_IMAGE}" System.map +do + if [ ! -f "${file}" ]; then + echo >&2 + echo >&2 " *** Missing file: ${file}" + echo >&2 ' *** You need to run "make" before "make install".' + echo >&2 + exit 1 + fi +done + +if [ -n "${INSTALL_PATH}" ] && ! [ -e "${INSTALL_PATH}" ]; then + mkdir -p "${INSTALL_PATH}" +fi + +# User/arch may have a custom install script +for file in "${HOME}/bin/${INSTALLKERNEL}" \ + "/sbin/${INSTALLKERNEL}" \ + "${srctree}/arch/${SRCARCH}/install.sh" \ + "${srctree}/arch/${SRCARCH}/boot/install.sh" +do + if [ ! -x "${file}" ]; then + continue + fi + + # installkernel(8) says the parameters are like follows: + # + # installkernel version zImage System.map [directory] + exec "${file}" "${KERNELRELEASE}" "${KBUILD_IMAGE}" System.map "${INSTALL_PATH}" +done + +echo "No install script found" >&2 +exit 1 -- cgit v1.3.1