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.clean | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) create mode 100644 scripts/Makefile.clean (limited to 'scripts/Makefile.clean') diff --git a/scripts/Makefile.clean b/scripts/Makefile.clean new file mode 100644 index 000000000..6ead00ec7 --- /dev/null +++ b/scripts/Makefile.clean @@ -0,0 +1,63 @@ +# SPDX-License-Identifier: GPL-2.0 +# ========================================================================== +# Cleaning up +# ========================================================================== + +src := $(srcroot)/$(obj) + +PHONY := __clean +__clean: + +include $(srctree)/scripts/Kbuild.include +include $(kbuild-file) + +# Figure out what we need to build from the various variables +# ========================================================================== + +subdir-ymn := $(sort $(subdir-y) $(subdir-m) $(subdir-) \ + $(patsubst %/,%, $(filter %/, $(obj-y) $(obj-m) $(obj-)))) + +# Add subdir path + +subdir-ymn := $(addprefix $(obj)/,$(subdir-ymn)) + +# build a list of files to remove, usually relative to the current +# directory + +__clean-files := \ + $(clean-files) $(targets) $(hostprogs) $(userprogs) \ + $(extra-y) $(extra-m) $(extra-) \ + $(always-y) $(always-m) $(always-) \ + $(hostprogs-always-y) $(hostprogs-always-m) $(hostprogs-always-) \ + $(userprogs-always-y) $(userprogs-always-m) $(userprogs-always-) + +__clean-files := $(filter-out $(no-clean-files), $(__clean-files)) + +__clean-files := $(wildcard $(addprefix $(obj)/, $(__clean-files))) + +# ========================================================================== + +# To make this rule robust against "Argument list too long" error, +# remove $(obj)/ prefix, and restore it by a shell command. +quiet_cmd_clean = CLEAN $(obj) + cmd_clean = printf '$(obj)/%s ' $(patsubst $(obj)/%,%,$(__clean-files)) | xargs rm -rf + +__clean: $(subdir-ymn) +ifneq ($(strip $(__clean-files)),) + $(call cmd,clean) +endif + @: + + +# =========================================================================== +# Generic stuff +# =========================================================================== + +# Descending +# --------------------------------------------------------------------------- + +PHONY += $(subdir-ymn) +$(subdir-ymn): + $(Q)$(MAKE) $(clean)=$@ + +.PHONY: $(PHONY) -- cgit v1.3.1