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 --- fs/proc/Makefile | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) create mode 100644 fs/proc/Makefile (limited to 'fs/proc/Makefile') diff --git a/fs/proc/Makefile b/fs/proc/Makefile new file mode 100644 index 000000000..8bc615ff8 --- /dev/null +++ b/fs/proc/Makefile @@ -0,0 +1,38 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for the Linux proc filesystem routines. +# + +obj-y += proc.o + +CFLAGS_task_mmu.o += -Wno-override-init +proc-y := nommu.o task_nommu.o +proc-$(CONFIG_MMU) := task_mmu.o + +proc-y += inode.o root.o base.o generic.o array.o \ + fd.o +proc-$(CONFIG_TTY) += proc_tty.o +proc-y += cmdline.o +proc-y += consoles.o +proc-y += cpuinfo.o +proc-y += devices.o +ifneq ($(CONFIG_GENERIC_IRQ_SHOW),y) +proc-y += interrupts.o +endif +proc-y += loadavg.o +proc-y += meminfo.o +proc-y += stat.o +proc-y += uptime.o +proc-y += util.o +proc-y += version.o +proc-y += softirqs.o +proc-y += namespaces.o +proc-y += self.o +proc-y += thread_self.o +proc-$(CONFIG_PROC_SYSCTL) += proc_sysctl.o +proc-$(CONFIG_NET) += proc_net.o +proc-$(CONFIG_PROC_KCORE) += kcore.o +proc-$(CONFIG_PROC_VMCORE) += vmcore.o +proc-$(CONFIG_PRINTK) += kmsg.o +proc-$(CONFIG_PROC_PAGE_MONITOR) += page.o +proc-$(CONFIG_BOOT_CONFIG) += bootconfig.o -- cgit v1.3.1