2023-09-23 02:22:56

by Kees Cook

Subject: [PATCH] i3c/master/mipi-i3c-hci: Annotate struct hci_rings_data 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 hci_rings_data.

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

Cc: Alexandre Belloni <[email protected]>
Cc: Nicolas Pitre <[email protected]>
Cc: Len Baker <[email protected]>
Cc: Boris Brezillon <[email protected]>
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
---
drivers/i3c/master/mipi-i3c-hci/dma.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i3c/master/mipi-i3c-hci/dma.c b/drivers/i3c/master/mipi-i3c-hci/dma.c
index 2990ac9eaade..a1ecdfc35641 100644
--- a/drivers/i3c/master/mipi-i3c-hci/dma.c
+++ b/drivers/i3c/master/mipi-i3c-hci/dma.c
@@ -139,7 +139,7 @@ struct hci_rh_data {

struct hci_rings_data {
unsigned int total;
- struct hci_rh_data headers[];
+ struct hci_rh_data headers[] __counted_by(total);
};

struct hci_dma_dev_ibi_data {
--
2.34.1

2023-09-23 08:29:44

by Gustavo A. R. Silva

Subject: Re: [PATCH] i3c/master/mipi-i3c-hci: Annotate struct hci_rings_data with __counted_by

On 9/22/23 11:50, 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 hci_rings_data.
>
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
>
> Cc: Alexandre Belloni <[email protected]>
> Cc: Nicolas Pitre <[email protected]>
> Cc: Len Baker <[email protected]>
> Cc: Boris Brezillon <[email protected]>
> Cc: [email protected]
> Signed-off-by: Kees Cook <[email protected]>

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

Thanks
--
Gustavo

> ---
> drivers/i3c/master/mipi-i3c-hci/dma.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/i3c/master/mipi-i3c-hci/dma.c b/drivers/i3c/master/mipi-i3c-hci/dma.c
> index 2990ac9eaade..a1ecdfc35641 100644
> --- a/drivers/i3c/master/mipi-i3c-hci/dma.c
> +++ b/drivers/i3c/master/mipi-i3c-hci/dma.c
> @@ -139,7 +139,7 @@ struct hci_rh_data {
>
> struct hci_rings_data {
> unsigned int total;
> - struct hci_rh_data headers[];
> + struct hci_rh_data headers[] __counted_by(total);
> };
>
> struct hci_dma_dev_ibi_data {

2023-09-26 04:41:50

by Alexandre Belloni

Subject: Re: [PATCH] i3c/master/mipi-i3c-hci: Annotate struct hci_rings_data with __counted_by

On Fri, 22 Sep 2023 10:50:19 -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 hci_rings_data.
>
> [...]

Applied, thanks!

[1/1] i3c/master/mipi-i3c-hci: Annotate struct hci_rings_data with __counted_by
commit: 751d377f0f7a09d6122de0e2232133524568c52b

Best regards,

--
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com