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 --- lib/tests/module/Makefile | 14 ++++++++++++++ 1 file changed, 14 insertions(+) create mode 100644 lib/tests/module/Makefile (limited to 'lib/tests/module/Makefile') diff --git a/lib/tests/module/Makefile b/lib/tests/module/Makefile new file mode 100644 index 000000000..2f3e1a772 --- /dev/null +++ b/lib/tests/module/Makefile @@ -0,0 +1,14 @@ +obj-$(CONFIG_TEST_KALLSYMS_A) += test_kallsyms_a.o +obj-$(CONFIG_TEST_KALLSYMS_B) += test_kallsyms_b.o +obj-$(CONFIG_TEST_KALLSYMS_C) += test_kallsyms_c.o +obj-$(CONFIG_TEST_KALLSYMS_D) += test_kallsyms_d.o + +quiet_cmd_gen_test_kallsyms = GEN $@ + cmd_gen_test_kallsyms = $< $@ \ + $(CONFIG_TEST_KALLSYMS_NUMSYMS) \ + $(CONFIG_TEST_KALLSYMS_SCALE_FACTOR) + +$(obj)/%.c: $(src)/gen_test_kallsyms.sh FORCE + $(call if_changed,gen_test_kallsyms) + +targets += $(foreach x, a b c d, test_kallsyms_$(x).c) -- cgit v1.3.1