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/package/gen-diff-patch | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) create mode 100755 scripts/package/gen-diff-patch (limited to 'scripts/package/gen-diff-patch') diff --git a/scripts/package/gen-diff-patch b/scripts/package/gen-diff-patch new file mode 100755 index 000000000..f272f7770 --- /dev/null +++ b/scripts/package/gen-diff-patch @@ -0,0 +1,38 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0-only + +set -eu + +diff_patch=$1 + +mkdir -p "$(dirname "${diff_patch}")" + +git -C "${srctree:-.}" diff HEAD > "${diff_patch}" + +if [ ! -s "${diff_patch}" ] || + [ -z "$(git -C "${srctree:-.}" ls-files --other --exclude-standard | head -n1)" ]; then + exit +fi + +# The source tarball, which is generated by 'git archive', contains everything +# you committed in the repository. If you have local diff ('git diff HEAD'), +# it will go into ${diff_patch}. If untracked files are remaining, the resulting +# source package may not be correct. +# +# Examples: +# - You modified a source file to add #include "new-header.h" +# but forgot to add new-header.h +# - You modified a Makefile to add 'obj-$(CONFIG_FOO) += new-dirver.o' +# but you forgot to add new-driver.c +# +# You need to commit them, or at least stage them by 'git add'. +# +# This script does not take care of untracked files because doing so would +# introduce additional complexity. Instead, print a warning message here if +# untracked files are found. +# If all untracked files are just garbage, you can ignore this warning. +echo >&2 "============================ WARNING ============================" +echo >&2 "Your working tree has diff from HEAD, and also untracked file(s)." +echo >&2 "Please make sure you did 'git add' for all new files you need in" +echo >&2 "the source package." +echo >&2 "=================================================================" -- cgit v1.3.1