2023-09-23 02:27:49

by Kees Cook

Subject: [PATCH] power: supply: axp20x_usb_power: Annotate struct axp20x_usb_power 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 axp20x_usb_power.

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

Cc: Sebastian Reichel <[email protected]>
Cc: Chen-Yu Tsai <[email protected]>
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
---
drivers/power/supply/axp20x_usb_power.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/power/supply/axp20x_usb_power.c b/drivers/power/supply/axp20x_usb_power.c
index bde17406c130..e23308ad4cc7 100644
--- a/drivers/power/supply/axp20x_usb_power.c
+++ b/drivers/power/supply/axp20x_usb_power.c
@@ -73,7 +73,7 @@ struct axp20x_usb_power {
unsigned int old_status;
unsigned int online;
unsigned int num_irqs;
- unsigned int irqs[];
+ unsigned int irqs[] __counted_by(num_irqs);
};

static bool axp20x_usb_vbus_needs_polling(struct axp20x_usb_power *power)
--
2.34.1

2023-09-23 03:52:58

by Sebastian Reichel

Subject: Re: [PATCH] power: supply: axp20x_usb_power: Annotate struct axp20x_usb_power with __counted_by

On Fri, 22 Sep 2023 10:53:58 -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 axp20x_usb_power.
>
> [...]

Applied, thanks!

[1/1] power: supply: axp20x_usb_power: Annotate struct axp20x_usb_power with __counted_by
commit: de1ca06bc0364a58ba0889d97a7a094d87dd5477

Best regards,
--
Sebastian Reichel <[email protected]>

2023-09-23 09:06:31

by Gustavo A. R. Silva

Subject: Re: [PATCH] power: supply: axp20x_usb_power: Annotate struct axp20x_usb_power with __counted_by

On Fri, Sep 22, 2023 at 10:53:58AM -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 axp20x_usb_power.
>
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
>
> Cc: Sebastian Reichel <[email protected]>
> Cc: Chen-Yu Tsai <[email protected]>
> Cc: [email protected]
> Signed-off-by: Kees Cook <[email protected]>

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

Thanks
--
Gustavo

> ---
> drivers/power/supply/axp20x_usb_power.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/power/supply/axp20x_usb_power.c b/drivers/power/supply/axp20x_usb_power.c
> index bde17406c130..e23308ad4cc7 100644
> --- a/drivers/power/supply/axp20x_usb_power.c
> +++ b/drivers/power/supply/axp20x_usb_power.c
> @@ -73,7 +73,7 @@ struct axp20x_usb_power {
> unsigned int old_status;
> unsigned int online;
> unsigned int num_irqs;
> - unsigned int irqs[];
> + unsigned int irqs[] __counted_by(num_irqs);
> };
>
> static bool axp20x_usb_vbus_needs_polling(struct axp20x_usb_power *power)
> --
> 2.34.1
>
>