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 --- arch/arm/common/Makefile | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) create mode 100644 arch/arm/common/Makefile (limited to 'arch/arm/common/Makefile') diff --git a/arch/arm/common/Makefile b/arch/arm/common/Makefile new file mode 100644 index 000000000..973338107 --- /dev/null +++ b/arch/arm/common/Makefile @@ -0,0 +1,17 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for the linux kernel. +# + +obj-y += firmware.o + +obj-$(CONFIG_SA1111) += sa1111.o +obj-$(CONFIG_KRAIT_L2_ACCESSORS) += krait-l2-accessors.o +obj-$(CONFIG_SHARP_LOCOMO) += locomo.o +obj-$(CONFIG_SHARP_PARAM) += sharpsl_param.o +obj-$(CONFIG_SHARP_SCOOP) += scoop.o +obj-$(CONFIG_CPU_V7) += secure_cntvoff.o +obj-$(CONFIG_MCPM) += mcpm_head.o mcpm_entry.o mcpm_platsmp.o vlock.o +CFLAGS_REMOVE_mcpm_entry.o = -pg +obj-$(CONFIG_BL_SWITCHER) += bL_switcher.o +obj-$(CONFIG_BL_SWITCHER_DUMMY_IF) += bL_switcher_dummy_if.o -- cgit v1.3.1