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| author | Ali Ahmet Memis <ali@iusegentoo.com> | 2026-08-21 01:45:27 +0000 |
|---|---|---|
| committer | Stafford Horne <shorne@gmail.com> | 2026-08-29 07:32:26 +0100 |
| commit | 78004e9a87f240df03e2f73120d291763c32e0a7 (patch) | |
| tree | 137c22dd795222931b9d2bf2501d37cd766741aa /tools/bootconfig/Makefile | |
| download | linux-stable-78004e9a87f240df03e2f73120d291763c32e0a7.tar.gz linux-stable-78004e9a87f240df03e2f73120d291763c32e0a7.zip | |
openrisc: fix arbitrary kernel memory access via or1k_atomic syscallgrafted
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 <ali@iusegentoo.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Diffstat (limited to 'tools/bootconfig/Makefile')
| -rw-r--r-- | tools/bootconfig/Makefile | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/tools/bootconfig/Makefile b/tools/bootconfig/Makefile new file mode 100644 index 000000000..90eb47c9d --- /dev/null +++ b/tools/bootconfig/Makefile @@ -0,0 +1,30 @@ +# SPDX-License-Identifier: GPL-2.0 +# Makefile for bootconfig command +include ../scripts/Makefile.include + +bindir ?= /usr/bin + +ifeq ($(srctree),) +srctree := $(patsubst %/,%,$(dir $(CURDIR))) +srctree := $(patsubst %/,%,$(dir $(srctree))) +endif + +LIBSRC = $(srctree)/lib/bootconfig.c $(srctree)/include/linux/bootconfig.h +override CFLAGS += -Wall -g -I$(CURDIR)/include + +ALL_TARGETS := bootconfig +ALL_PROGRAMS := $(patsubst %,$(OUTPUT)%,$(ALL_TARGETS)) + +all: $(ALL_PROGRAMS) test + +$(OUTPUT)bootconfig: main.c include/linux/bootconfig.h $(LIBSRC) + $(CC) $(filter %.c,$^) $(CFLAGS) $(LDFLAGS) -o $@ + +test: $(ALL_PROGRAMS) test-bootconfig.sh + ./test-bootconfig.sh $(OUTPUT) + +install: $(ALL_PROGRAMS) + install $(OUTPUT)bootconfig $(DESTDIR)$(bindir) + +clean: + $(RM) -f $(OUTPUT)*.o $(ALL_PROGRAMS) |