2023-09-16 00:46:38

by Kees Cook

Subject: [PATCH] wifi: wcn36xx: Annotate struct wcn36xx_hal_ind_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 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 wcn36xx_hal_ind_msg.

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

Cc: Loic Poulain <[email protected]>
Cc: Kalle Valo <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
---
drivers/net/wireless/ath/wcn36xx/smd.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/wcn36xx/smd.h b/drivers/net/wireless/ath/wcn36xx/smd.h
index cf15cde2a364..2c1ed9e570bf 100644
--- a/drivers/net/wireless/ath/wcn36xx/smd.h
+++ b/drivers/net/wireless/ath/wcn36xx/smd.h
@@ -47,7 +47,7 @@ struct wcn36xx_fw_msg_status_rsp {
struct wcn36xx_hal_ind_msg {
struct list_head list;
size_t msg_len;
- u8 msg[];
+ u8 msg[] __counted_by(msg_len);
};

struct wcn36xx;
--
2.34.1

2023-09-21 21:15:19

by Kalle Valo

Subject: Re: [PATCH] wifi: wcn36xx: Annotate struct wcn36xx_hal_ind_msg with __counted_by

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 wcn36xx_hal_ind_msg.
>
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
>
> Cc: Loic Poulain <[email protected]>
> Cc: Kalle Valo <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: Kees Cook <[email protected]>
> Reviewed-by: Gustavo A. R. Silva <[email protected]>
> Signed-off-by: Kalle Valo <[email protected]>

Patch applied to ath-next branch of ath.git, thanks.

f8cbbb224b11 wifi: wcn36xx: Annotate struct wcn36xx_hal_ind_msg with __counted_by

--
https://patchwork.kernel.org/project/linux-wireless/patch/[email protected]/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches