2023-09-15 22:26:48

by Kees Cook

[permalink] [raw]
Subject: [PATCH] wifi: mt76: Annotate struct mt76_rx_tid 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 mt76_rx_tid.

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

Cc: Felix Fietkau <[email protected]>
Cc: Lorenzo Bianconi <[email protected]>
Cc: Ryder Lee <[email protected]>
Cc: Shayne Chen <[email protected]>
Cc: Sean Wang <[email protected]>
Cc: Kalle Valo <[email protected]>
Cc: Matthias Brugger <[email protected]>
Cc: AngeloGioacchino Del Regno <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
---
drivers/net/wireless/mediatek/mt76/mt76.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt76.h b/drivers/net/wireless/mediatek/mt76/mt76.h
index e8757865a3d0..03ef617b1527 100644
--- a/drivers/net/wireless/mediatek/mt76/mt76.h
+++ b/drivers/net/wireless/mediatek/mt76/mt76.h
@@ -376,7 +376,7 @@ struct mt76_rx_tid {

u8 started:1, stopped:1, timer_pending:1;

- struct sk_buff *reorder_buf[];
+ struct sk_buff *reorder_buf[] __counted_by(size);
};

#define MT_TX_CB_DMA_DONE BIT(0)
--
2.34.1


2023-10-06 20:21:25

by Kees Cook

[permalink] [raw]
Subject: Re: [PATCH] wifi: mt76: Annotate struct mt76_rx_tid with __counted_by

On Fri, Sep 15, 2023 at 01:06:12PM -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 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 mt76_rx_tid.

Friendly ping. Can this get picked up by the wifi tree, or should it go
via something else?

Thanks!

-Kees

>
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
>
> Cc: Felix Fietkau <[email protected]>
> Cc: Lorenzo Bianconi <[email protected]>
> Cc: Ryder Lee <[email protected]>
> Cc: Shayne Chen <[email protected]>
> Cc: Sean Wang <[email protected]>
> Cc: Kalle Valo <[email protected]>
> Cc: Matthias Brugger <[email protected]>
> Cc: AngeloGioacchino Del Regno <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: Kees Cook <[email protected]>
> ---
> drivers/net/wireless/mediatek/mt76/mt76.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/mediatek/mt76/mt76.h b/drivers/net/wireless/mediatek/mt76/mt76.h
> index e8757865a3d0..03ef617b1527 100644
> --- a/drivers/net/wireless/mediatek/mt76/mt76.h
> +++ b/drivers/net/wireless/mediatek/mt76/mt76.h
> @@ -376,7 +376,7 @@ struct mt76_rx_tid {
>
> u8 started:1, stopped:1, timer_pending:1;
>
> - struct sk_buff *reorder_buf[];
> + struct sk_buff *reorder_buf[] __counted_by(size);
> };
>
> #define MT_TX_CB_DMA_DONE BIT(0)
> --
> 2.34.1
>

--
Kees Cook

2023-10-07 03:43:45

by Kalle Valo

[permalink] [raw]
Subject: Re: [PATCH] wifi: mt76: Annotate struct mt76_rx_tid with __counted_by

Kees Cook <[email protected]> writes:

> On Fri, Sep 15, 2023 at 01:06:12PM -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 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 mt76_rx_tid.
>
> Friendly ping. Can this get picked up by the wifi tree, or should it go
> via something else?

It's already in mt76 pull request and should be in wireless-next next
week:

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

--
https://patchwork.kernel.org/project/linux-wireless/list/

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