2023-09-22 17:35:04

by Kees Cook

Subject: [PATCH 2/9] drm/amdgpu/discovery: Annotate struct ip_hw_instance 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 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 ip_hw_instance.

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

Cc: Alex Deucher <[email protected]>
Cc: "Christian König" <[email protected]>
Cc: "Pan, Xinhui" <[email protected]>
Cc: David Airlie <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: Hawking Zhang <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
index d1bc7b212520..be4c97a3d7bf 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
@@ -662,7 +662,7 @@ struct ip_hw_instance {
u8 harvest;

int num_base_addresses;
- u32 base_addr[];
+ u32 base_addr[] __counted_by(num_base_addresses);
};

struct ip_hw_id {
--
2.34.1

2023-09-22 23:05:02

by Gustavo A. R. Silva

Subject: Re: [PATCH 2/9] drm/amdgpu/discovery: Annotate struct ip_hw_instance with __counted_by

On 9/22/23 11:32, 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 ip_hw_instance.
>
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
>
> Cc: Alex Deucher <[email protected]>
> Cc: "Christian König" <[email protected]>
> Cc: "Pan, Xinhui" <[email protected]>
> Cc: David Airlie <[email protected]>
> Cc: Daniel Vetter <[email protected]>
> Cc: Hawking Zhang <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: Kees Cook <[email protected]>

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

Thanks
--
Gustavo

> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> index d1bc7b212520..be4c97a3d7bf 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> @@ -662,7 +662,7 @@ struct ip_hw_instance {
> u8 harvest;
>
> int num_base_addresses;
> - u32 base_addr[];
> + u32 base_addr[] __counted_by(num_base_addresses);
> };
>
> struct ip_hw_id {

2023-09-23 01:53:00

by Alex Deucher

Subject: Re: [PATCH 2/9] drm/amdgpu/discovery: Annotate struct ip_hw_instance with __counted_by

On Fri, Sep 22, 2023 at 1:33 PM Kees Cook <[email protected]> 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 ip_hw_instance.
>
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
>
> Cc: Alex Deucher <[email protected]>
> Cc: "Christian König" <[email protected]>
> Cc: "Pan, Xinhui" <[email protected]>
> Cc: David Airlie <[email protected]>
> Cc: Daniel Vetter <[email protected]>
> Cc: Hawking Zhang <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: Kees Cook <[email protected]>

Acked-by: Alex Deucher <[email protected]>

> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> index d1bc7b212520..be4c97a3d7bf 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> @@ -662,7 +662,7 @@ struct ip_hw_instance {
> u8 harvest;
>
> int num_base_addresses;
> - u32 base_addr[];
> + u32 base_addr[] __counted_by(num_base_addresses);
> };
>
> struct ip_hw_id {
> --
> 2.34.1
>