Re: [PATCH] video: fbdev: mmp: Annotate struct mmphw_ctrl with __counted_by

[Helge Deller]

On 9/23/23 18:33, Gustavo A. R. Silva wrote:

On 9/22/23 11:51, Kees Cook wrote:

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct mmphw_ctrl.

[1] 
https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Helge Deller 
Cc: linux-fb...@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Kees Cook 


Reviewed-by: Gustavo A. R. Silva 


Both fbdev patches applied to fbdev git tree.

Thank you Kees!

Helge

Re: [PATCH] video: fbdev: mmp: Annotate struct mmphw_ctrl with __counted_by

[Gustavo A. R. Silva]

On 9/22/23 11:51, Kees Cook wrote:

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct mmphw_ctrl.

[1] 
https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Helge Deller 
Cc: linux-fb...@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Kees Cook 


Reviewed-by: Gustavo A. R. Silva 

Thanks
--
Gustavo


---
  drivers/video/fbdev/mmp/hw/mmp_ctrl.h | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/video/fbdev/mmp/hw/mmp_ctrl.h 
b/drivers/video/fbdev/mmp/hw/mmp_ctrl.h
index 167585a889d3..719b99a9bc77 100644
--- a/drivers/video/fbdev/mmp/hw/mmp_ctrl.h
+++ b/drivers/video/fbdev/mmp/hw/mmp_ctrl.h
@@ -1406,7 +1406,7 @@ struct mmphw_ctrl {
  
  	/*pathes*/

int path_num;
-   struct mmphw_path_plat path_plats[];
+   struct mmphw_path_plat path_plats[] __counted_by(path_num);
  };
  
  static inline int overlay_is_vid(struct mmp_overlay *overlay)

[PATCH] video: fbdev: mmp: Annotate struct mmphw_ctrl with __counted_by

[Kees Cook]

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct mmphw_ctrl.

[1] 
https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Helge Deller 
Cc: linux-fb...@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Kees Cook 
---
 drivers/video/fbdev/mmp/hw/mmp_ctrl.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/video/fbdev/mmp/hw/mmp_ctrl.h 
b/drivers/video/fbdev/mmp/hw/mmp_ctrl.h
index 167585a889d3..719b99a9bc77 100644
--- a/drivers/video/fbdev/mmp/hw/mmp_ctrl.h
+++ b/drivers/video/fbdev/mmp/hw/mmp_ctrl.h
@@ -1406,7 +1406,7 @@ struct mmphw_ctrl {
 
/*pathes*/
int path_num;
-   struct mmphw_path_plat path_plats[];
+   struct mmphw_path_plat path_plats[] __counted_by(path_num);
 };
 
 static inline int overlay_is_vid(struct mmp_overlay *overlay)
-- 
2.34.1