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/Makefile.dtbinst | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) create mode 100644 scripts/Makefile.dtbinst (limited to 'scripts/Makefile.dtbinst') diff --git a/scripts/Makefile.dtbinst b/scripts/Makefile.dtbinst new file mode 100644 index 000000000..9d920419a --- /dev/null +++ b/scripts/Makefile.dtbinst @@ -0,0 +1,43 @@ +# SPDX-License-Identifier: GPL-2.0 +# ========================================================================== +# Installing dtb files +# +# Installs all dtb files listed in $(dtb-y) either in the +# INSTALL_DTBS_PATH directory or the default location: +# +# $INSTALL_PATH/dtbs/$KERNELRELEASE +# ========================================================================== + +PHONY := __dtbs_install +__dtbs_install: + +include include/config/auto.conf +include $(srctree)/scripts/Kbuild.include + +dst := $(INSTALL_DTBS_PATH) + +quiet_cmd_dtb_install = INSTALL $@ + cmd_dtb_install = install -D -m 0644 $< $@ + +$(dst)/%: $(obj)/% + $(call cmd,dtb_install) + +dtbs := $(patsubst $(obj)/%,%,$(call read-file, $(obj)/dtbs-list)) + +ifdef CONFIG_ARCH_WANT_FLAT_DTB_INSTALL + +define gen_install_rules +$(dst)/%: $(obj)/$(1)% + $$(call cmd,dtb_install) +endef + +$(foreach d, $(sort $(dir $(dtbs))), $(eval $(call gen_install_rules,$(d)))) + +dtbs := $(notdir $(dtbs)) + +endif # CONFIG_ARCH_WANT_FLAT_DTB_INSTALL + +__dtbs_install: $(addprefix $(dst)/, $(dtbs)) + @: + +.PHONY: $(PHONY) -- cgit v1.3.1