LinuxLists.cc - [PATCH] drm/i915/guc: Annotate struct ct_incoming_msg with __counted

2023-10-06 20:18:17

Subject: [PATCH] drm/i915/guc: Annotate struct ct_incoming_msg with __counted_by

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 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 ct_incoming_msg.

Cc: Jani Nikula <[email protected]>
Cc: Joonas Lahtinen <[email protected]>
Cc: Rodrigo Vivi <[email protected]>
Cc: Tvrtko Ursulin <[email protected]>
Cc: David Airlie <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: "Gustavo A. R. Silva" <[email protected]>
Cc: John Harrison <[email protected]>
Cc: Matthew Brost <[email protected]>
Cc: Michal Wajdeczko <[email protected]>
Cc: Matt Roper <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
Signed-off-by: Kees Cook <[email protected]>
---
drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
index 6e22af31513a..c33210ead1ef 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
@@ -96,7 +96,7 @@ struct ct_request {
struct ct_incoming_msg {
struct list_head link;
u32 size;
- u32 msg[];
+ u32 msg[] __counted_by(size);
};

enum { CTB_SEND = 0, CTB_RECV = 1 };
--
2.34.1

2023-10-06 20:47:48

by Gustavo A. R. Silva

[permalink] [raw]

Subject: Re: [PATCH] drm/i915/guc: Annotate struct ct_incoming_msg with __counted_by

On 10/6/23 22:17, 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 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 ct_incoming_msg.
>
> Cc: Jani Nikula <[email protected]>
> Cc: Joonas Lahtinen <[email protected]>
> Cc: Rodrigo Vivi <[email protected]>
> Cc: Tvrtko Ursulin <[email protected]>
> Cc: David Airlie <[email protected]>
> Cc: Daniel Vetter <[email protected]>
> Cc: "Gustavo A. R. Silva" <[email protected]>
> Cc: John Harrison <[email protected]>
> Cc: Matthew Brost <[email protected]>
> Cc: Michal Wajdeczko <[email protected]>
> Cc: Matt Roper <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
> Signed-off-by: Kees Cook <[email protected]>

Reviewed-by: Gustavo A. R. Silva <[email protected]>

Thanks!
--
Gustavo

> ---
> drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
> index 6e22af31513a..c33210ead1ef 100644
> --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
> +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
> @@ -96,7 +96,7 @@ struct ct_request {
> struct ct_incoming_msg {
> struct list_head link;
> u32 size;
> - u32 msg[];
> + u32 msg[] __counted_by(size);
> };
>
> enum { CTB_SEND = 0, CTB_RECV = 1 };

2023-10-06 21:03:05

by Andi Shyti

[permalink] [raw]

Subject: Re: [PATCH] drm/i915/guc: Annotate struct ct_incoming_msg with __counted_by

Hi Kees,

On Fri, Oct 06, 2023 at 01:17:45PM -0700, 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 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 ct_incoming_msg.
>
> Cc: Jani Nikula <[email protected]>
> Cc: Joonas Lahtinen <[email protected]>
> Cc: Rodrigo Vivi <[email protected]>
> Cc: Tvrtko Ursulin <[email protected]>
> Cc: David Airlie <[email protected]>
> Cc: Daniel Vetter <[email protected]>
> Cc: "Gustavo A. R. Silva" <[email protected]>
> Cc: John Harrison <[email protected]>
> Cc: Matthew Brost <[email protected]>
> Cc: Michal Wajdeczko <[email protected]>
> Cc: Matt Roper <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
> Signed-off-by: Kees Cook <[email protected]>

Reviewed-by: Andi Shyti <[email protected]>

Andi

2023-10-09 12:28:57

by Andi Shyti

[permalink] [raw]