Re: [PATCH] mtd: rawnand: marvell: Annotate struct marvell_nand_chip with __counted_by

From: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
To: Kees Cook <keescook@chromium.org>,
	Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Richard Weinberger <richard@nod.at>,
	Vignesh Raghavendra <vigneshr@ti.com>,
	linux-mtd@lists.infradead.org,
	Nathan Chancellor <nathan@kernel.org>,
	Nick Desaulniers <ndesaulniers@google.com>,
	Tom Rix <trix@redhat.com>,
	linux-kernel@vger.kernel.org, llvm@lists.linux.dev,
	linux-hardening@vger.kernel.org
Subject: Re: [PATCH] mtd: rawnand: marvell: Annotate struct marvell_nand_chip with __counted_by
Date: Fri, 15 Sep 2023 14:49:22 -0600	[thread overview]
Message-ID: <f3ff7e46-2c9b-e751-ad1e-53d1ee7f3a02@embeddedor.com> (raw)
In-Reply-To: <20230915201243.never.235-kees@kernel.org>


On 9/15/23 14:12, 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 marvell_nand_chip.
> 
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
> 
> Cc: Miquel Raynal <miquel.raynal@bootlin.com>
> Cc: Richard Weinberger <richard@nod.at>
> Cc: Vignesh Raghavendra <vigneshr@ti.com>
> Cc: linux-mtd@lists.infradead.org
> Signed-off-by: Kees Cook <keescook@chromium.org>

Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Thanks
-- 
Gustavo

> ---
>   drivers/mtd/nand/raw/marvell_nand.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/mtd/nand/raw/marvell_nand.c b/drivers/mtd/nand/raw/marvell_nand.c
> index b841a81cb128..a46698744850 100644
> --- a/drivers/mtd/nand/raw/marvell_nand.c
> +++ b/drivers/mtd/nand/raw/marvell_nand.c
> @@ -348,7 +348,7 @@ struct marvell_nand_chip {
>   	int addr_cyc;
>   	int selected_die;
>   	unsigned int nsels;
> -	struct marvell_nand_chip_sel sels[];
> +	struct marvell_nand_chip_sel sels[] __counted_by(nsels);
>   };
>   
>   static inline struct marvell_nand_chip *to_marvell_nand(struct nand_chip *chip)