[06/22,RESEND] stackleak: add declarations for global functions

Commit Message

Arnd Bergmann Nov. 8, 2023, 12:58 p.m. UTC

From: Arnd Bergmann <[e-mail]>

With -Wmissing-prototypes enabled, the stackleak code produces a couple of
warnings that have no declarations because they are only called from assembler:

stackleak.c:127:25: error: no previous prototype for 'stackleak_erase' [-Werror=missing-prototypes]
stackleak.c:139:25: error: no previous prototype for 'stackleak_erase_on_task_stack' [-Werror=missing-prototypes]
stackleak.c:151:25: error: no previous prototype for 'stackleak_erase_off_task_stack' [-Werror=missing-prototypes]
stackleak.c:159:49: error: no previous prototype for 'stackleak_track_stack' [-Werror=missing-prototypes]

Add declarations to the stackleak header to shut up the warnings.

Signed-off-by: Arnd Bergmann <[e-mail]>
---
 include/linux/stackleak.h | 6 ++++++
 1 file changed, 6 insertions(+)

Comments

Kees Cook Nov. 8, 2023, 7:07 p.m. UTC | #1

On Wed, 08 Nov 2023 13:58:27 +0100, Arnd Bergmann wrote:
> With -Wmissing-prototypes enabled, the stackleak code produces a couple of
> warnings that have no declarations because they are only called from assembler:
> 
> stackleak.c:127:25: error: no previous prototype for 'stackleak_erase' [-Werror=missing-prototypes]
> stackleak.c:139:25: error: no previous prototype for 'stackleak_erase_on_task_stack' [-Werror=missing-prototypes]
> stackleak.c:151:25: error: no previous prototype for 'stackleak_erase_off_task_stack' [-Werror=missing-prototypes]
> stackleak.c:159:49: error: no previous prototype for 'stackleak_track_stack' [-Werror=missing-prototypes]
> 
> [...]

Applied to for-next/hardening, thanks!

[06/22] stackleak: add declarations for global functions
        https://git.kernel.org/kees/c/65120498aaf8

Take care,

Patch

diff --git a/include/linux/stackleak.h b/include/linux/stackleak.h
index c36e7a3b45e7..3be2cb564710 100644
--- a/include/linux/stackleak.h
+++ b/include/linux/stackleak.h
@@ -14,6 +14,7 @@ 
 
 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK
 #include <asm/stacktrace.h>
+#include <linux/linkage.h>
 
 /*
  * The lowest address on tsk's stack which we can plausibly erase.
@@ -76,6 +77,11 @@  static inline void stackleak_task_init(struct task_struct *t)
 # endif
 }
 
+asmlinkage void noinstr stackleak_erase(void);
+asmlinkage void noinstr stackleak_erase_on_task_stack(void);
+asmlinkage void noinstr stackleak_erase_off_task_stack(void);
+void __no_caller_saved_registers noinstr stackleak_track_stack(void);
+
 #else /* !CONFIG_GCC_PLUGIN_STACKLEAK */
 static inline void stackleak_task_init(struct task_struct *t) { }
 #endif