Re: [PATCH] ocfs2: Annotate struct ocfs2_slot_info with __counted_by

[Joseph Qi]

On 9/16/23 4:15 AM, 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 ocfs2_slot_info.
> 
> [1] 
> https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
> 
> Cc: Mark Fasheh 
> Cc: Joel Becker 
> Cc: Joseph Qi 
> Cc: ocfs2-de...@lists.linux.dev
> Signed-off-by: Kees Cook 

Reviewed-by: Joseph Qi 
> ---
>  fs/ocfs2/slot_map.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/ocfs2/slot_map.c b/fs/ocfs2/slot_map.c
> index da7718cef735..e544c704b583 100644
> --- a/fs/ocfs2/slot_map.c
> +++ b/fs/ocfs2/slot_map.c
> @@ -37,7 +37,7 @@ struct ocfs2_slot_info {
>   unsigned int si_blocks;
>   struct buffer_head **si_bh;
>   unsigned int si_num_slots;
> - struct ocfs2_slot si_slots[];
> + struct ocfs2_slot si_slots[] __counted_by(si_num_slots);
>  };
>  
>  

Re: [PATCH] ocfs2: Annotate struct ocfs2_slot_info with __counted_by

[Gustavo A. R. Silva]

On 9/15/23 14:15, 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 ocfs2_slot_info.

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

Cc: Mark Fasheh 
Cc: Joel Becker 
Cc: Joseph Qi 
Cc: ocfs2-de...@lists.linux.dev
Signed-off-by: Kees Cook 


Reviewed-by: Gustavo A. R. Silva 

Thanks
--
Gustavo


---
  fs/ocfs2/slot_map.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ocfs2/slot_map.c b/fs/ocfs2/slot_map.c
index da7718cef735..e544c704b583 100644
--- a/fs/ocfs2/slot_map.c
+++ b/fs/ocfs2/slot_map.c
@@ -37,7 +37,7 @@ struct ocfs2_slot_info {
unsigned int si_blocks;
struct buffer_head **si_bh;
unsigned int si_num_slots;
-   struct ocfs2_slot si_slots[];
+   struct ocfs2_slot si_slots[] __counted_by(si_num_slots);
  };
  
  

[PATCH] ocfs2: Annotate struct ocfs2_slot_info 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 ocfs2_slot_info.

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

Cc: Mark Fasheh 
Cc: Joel Becker 
Cc: Joseph Qi 
Cc: ocfs2-de...@lists.linux.dev
Signed-off-by: Kees Cook 
---
 fs/ocfs2/slot_map.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ocfs2/slot_map.c b/fs/ocfs2/slot_map.c
index da7718cef735..e544c704b583 100644
--- a/fs/ocfs2/slot_map.c
+++ b/fs/ocfs2/slot_map.c
@@ -37,7 +37,7 @@ struct ocfs2_slot_info {
unsigned int si_blocks;
struct buffer_head **si_bh;
unsigned int si_num_slots;
-   struct ocfs2_slot si_slots[];
+   struct ocfs2_slot si_slots[] __counted_by(si_num_slots);
 };
 
 
-- 
2.34.1