2023-09-16 06:16:52

by Kees Cook

Subject: [PATCH] leds: cr0014114: Annotate struct cr0014114 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 cr0014114.

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

Cc: Pavel Machek <[email protected]>
Cc: Lee Jones <[email protected]>
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
---
drivers/leds/leds-cr0014114.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/leds/leds-cr0014114.c b/drivers/leds/leds-cr0014114.c
index b33bca397ea6..c9914fc51f20 100644
--- a/drivers/leds/leds-cr0014114.c
+++ b/drivers/leds/leds-cr0014114.c
@@ -56,7 +56,7 @@ struct cr0014114 {
struct spi_device *spi;
u8 *buf;
unsigned long delay;
- struct cr0014114_led leds[];
+ struct cr0014114_led leds[] __counted_by(count);
};

static void cr0014114_calc_crc(u8 *buf, const size_t len)
--
2.34.1

2023-09-20 13:47:31

by Lee Jones

Subject: Re: (subset) [PATCH] leds: cr0014114: Annotate struct cr0014114 with __counted_by

On Fri, 15 Sep 2023 13:09:48 -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 cr0014114.
>
> [...]

Applied, thanks!

[1/1] leds: cr0014114: Annotate struct cr0014114 with __counted_by
commit: dfd75548c30c4a27bcc4c81aed0287d2e8b62add

--
Lee Jones [李琼斯]