[PATCH] mtd: rawnand: sunxi: Annotate struct sunxi_nand_chip with __counted_by

[PATCH] mtd: rawnand: sunxi: Annotate struct sunxi_nand_chip with __counted_by

[Kees Cook]

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 sunxi_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: Chen-Yu Tsai <wens@csie.org>
Cc: Jernej Skrabec <jernej.skrabec@gmail.com>
Cc: Samuel Holland <samuel@sholland.org>
Cc: Manuel Dipolt <mdipolt@robart.cc>
Cc: linux-mtd@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-sunxi@lists.linux.dev
Signed-off-by: Kees Cook <keescook@chromium.org>
---
 drivers/mtd/nand/raw/sunxi_nand.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/nand/raw/sunxi_nand.c b/drivers/mtd/nand/raw/sunxi_nand.c
index 9abf38049d35..4ec17c8bce5a 100644
--- a/drivers/mtd/nand/raw/sunxi_nand.c
+++ b/drivers/mtd/nand/raw/sunxi_nand.c
@@ -197,7 +197,7 @@ struct sunxi_nand_chip {
 	u32 timing_cfg;
 	u32 timing_ctl;
 	int nsels;
-	struct sunxi_nand_chip_sel sels[];
+	struct sunxi_nand_chip_sel sels[] __counted_by(nsels);
 };
 
 static inline struct sunxi_nand_chip *to_sunxi_nand(struct nand_chip *nand)
-- 
2.34.1

Re: [PATCH] mtd: rawnand: sunxi: Annotate struct sunxi_nand_chip with __counted_by

[Gustavo A. R. Silva]

On 9/15/23 14:13, 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 sunxi_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: Chen-Yu Tsai <wens@csie.org>
> Cc: Jernej Skrabec <jernej.skrabec@gmail.com>
> Cc: Samuel Holland <samuel@sholland.org>
> Cc: Manuel Dipolt <mdipolt@robart.cc>
> Cc: linux-mtd@lists.infradead.org
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-sunxi@lists.linux.dev
> Signed-off-by: Kees Cook <keescook@chromium.org>

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

Thanks
-- 
Gustavo

> ---
>   drivers/mtd/nand/raw/sunxi_nand.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/mtd/nand/raw/sunxi_nand.c b/drivers/mtd/nand/raw/sunxi_nand.c
> index 9abf38049d35..4ec17c8bce5a 100644
> --- a/drivers/mtd/nand/raw/sunxi_nand.c
> +++ b/drivers/mtd/nand/raw/sunxi_nand.c
> @@ -197,7 +197,7 @@ struct sunxi_nand_chip {
>   	u32 timing_cfg;
>   	u32 timing_ctl;
>   	int nsels;
> -	struct sunxi_nand_chip_sel sels[];
> +	struct sunxi_nand_chip_sel sels[] __counted_by(nsels);
>   };
>   
>   static inline struct sunxi_nand_chip *to_sunxi_nand(struct nand_chip *nand)

Re: [PATCH] mtd: rawnand: sunxi: Annotate struct sunxi_nand_chip with __counted_by

[Miquel Raynal]

On Fri, 2023-09-15 at 20:13:01 UTC, 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 sunxi_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: Chen-Yu Tsai <wens@csie.org>
> Cc: Jernej Skrabec <jernej.skrabec@gmail.com>
> Cc: Samuel Holland <samuel@sholland.org>
> Cc: Manuel Dipolt <mdipolt@robart.cc>
> Cc: linux-mtd@lists.infradead.org
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-sunxi@lists.linux.dev
> Signed-off-by: Kees Cook <keescook@chromium.org>
> Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git mtd/next, thanks.

Miquel