diff mbox series

[v1,12/19] ACPICA: Introduce ACPI_NONSTRING

Message ID 1841930.VLH7GnMWUR@rjwysocki.net
State New
Headers show
Series ACPICA: ACPICA 20250404 | expand

Commit Message

Rafael J. Wysocki April 25, 2025, 7:27 p.m. UTC 
From: Kees Cook <kees@kernel.org>

ACPICA commit 878823ca20f1987cba0c9d4c1056be0d117ea4fe

In order to distinguish character arrays from C Strings (i.e. strings with
a terminating NUL character), add support for the "nonstring" attribute
provided by GCC. (A better name might be "ACPI_NONCSTRING", but that's
the attribute name, so stick to the existing naming convention.)

GCC 15's -Wunterminated-string-initialization will warn about truncation
of the NUL byte for string initializers unless the destination is marked
with "nonstring". Prepare for applying this attribute to the project.

Link: https://github.com/acpica/acpica/commit/878823ca
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 include/acpi/actypes.h        | 4 ++++
 include/acpi/platform/acgcc.h | 8 ++++++++
 2 files changed, 12 insertions(+)

Comments

Kees Cook April 30, 2025, 6:35 p.m. UTC | #1 
On Fri, Apr 25, 2025 at 09:27:58PM +0200, Rafael J. Wysocki wrote:
> From: Kees Cook <kees@kernel.org>
> 
> ACPICA commit 878823ca20f1987cba0c9d4c1056be0d117ea4fe
> 
> In order to distinguish character arrays from C Strings (i.e. strings with
> a terminating NUL character), add support for the "nonstring" attribute
> provided by GCC. (A better name might be "ACPI_NONCSTRING", but that's
> the attribute name, so stick to the existing naming convention.)
> 
> GCC 15's -Wunterminated-string-initialization will warn about truncation
> of the NUL byte for string initializers unless the destination is marked
> with "nonstring". Prepare for applying this attribute to the project.
> 
> Link: https://github.com/acpica/acpica/commit/878823ca
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Whoops, I missed adding my S-o-b to the original upstream ACPICA commit.
Please consider this:

Signed-off-by: Kees Cook <kees@kernel.org>
diff mbox series

Patch

diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h
index 80767e8bf3ad..f7b3c4a4b7e7 100644
--- a/include/acpi/actypes.h
+++ b/include/acpi/actypes.h
@@ -1327,4 +1327,8 @@  typedef enum {
 #define ACPI_FLEX_ARRAY(TYPE, NAME)     TYPE NAME[0]
 #endif
 
+#ifndef ACPI_NONSTRING
+#define ACPI_NONSTRING		/* No terminating NUL character */
+#endif
+
 #endif				/* __ACTYPES_H__ */
diff --git a/include/acpi/platform/acgcc.h b/include/acpi/platform/acgcc.h
index 04b4bf620517..68e9379623e6 100644
--- a/include/acpi/platform/acgcc.h
+++ b/include/acpi/platform/acgcc.h
@@ -72,4 +72,12 @@ 
                 TYPE NAME[];                    \
         }
 
+/*
+ * Explicitly mark strings that lack a terminating NUL character so
+ * that ACPICA can be built with -Wunterminated-string-initialization.
+ */
+#if __has_attribute(__nonstring__)
+#define ACPI_NONSTRING __attribute__((__nonstring__))
+#endif
+
 #endif				/* __ACGCC_H__ */