-----Original Message-----
From: Nick Desaulniers <ndesaulniers@google.com>
Sent: Monday, June 1, 2020 4:18 PM
To: Moore, Robert <redacted>; Kaneda, Erik
[off-list ref]; Wysocki, Rafael J [off-list ref];
Len Brown [off-list ref]
Cc: Ard Biesheuvel <ardb@kernel.org>; dvyukov@google.com;
glider@google.com; guohanjun@huawei.com; linux-arm-
kernel@lists.infradead.org; linux-kernel@vger.kernel.org;
lorenzo.pieralisi@arm.com; mark.rutland@arm.com;
ndesaulniers@google.com; pcc@google.com; rjw@rjwysocki.net;
will@kernel.org; stable@vger.kernel.org; linux-acpi@vger.kernel.org;
devel@acpica.org
Subject: [PATCH] ACPICA: fix UBSAN warning using __builtin_offsetof
Hi,
Will reported UBSAN warnings:
UBSAN: null-ptr-deref in drivers/acpi/acpica/tbfadt.c:459:37
UBSAN: null-ptr-deref in arch/arm64/kernel/smp.c:596:6
Looks like the emulated offsetof macro ACPI_OFFSET is causing these. We
can avoid this by using the compiler builtin, __builtin_offsetof.
I'll take a look at this tomorrow
The non-kernel runtime of UBSAN would print:
runtime error: member access within null pointer of type for this macro.
actypes.h is owned by ACPICA so we typically do not allow compiler-specific
extensions because the code is intended to be compiled using the C99 standard
without compiler extensions. We could allow this sort of thing in a Linux-specific
header file like include/acpi/platform/aclinux.h but I'll take a look at the error as well..
Erik
quoted hunk ↗ jump to hunk
Link: https://lore.kernel.org/lkml/20200521100952.GA5360@willie-the-truck/ (local)
Cc: <redacted>
Reported-by: Will Deacon <will@kernel.org>
Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
---
include/acpi/actypes.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h index
4defed58ea33..04359c70b198 100644
--- a/include/acpi/actypes.h
+++ b/include/acpi/actypes.h
@@ -508,7 +508,7 @@ typedef u64 acpi_integer;
#define ACPI_TO_POINTER(i) ACPI_CAST_PTR (void, (acpi_size) (i))
#define ACPI_TO_INTEGER(p) ACPI_PTR_DIFF (p, (void *) 0)
-#define ACPI_OFFSET(d, f) ACPI_PTR_DIFF (&(((d *) 0)->f), (void *)
0)
+#define ACPI_OFFSET(d, f) __builtin_offsetof(d, f)
#define ACPI_PHYSADDR_TO_PTR(i) ACPI_TO_POINTER(i)
#define ACPI_PTR_TO_PHYSADDR(i) ACPI_TO_INTEGER(i)
--
2.27.0.rc2.251.g90737beb825-goog
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel