[PATCH] clk: hisilicon: Use devm_kcalloc() instead of devm_kzalloc()

[PATCH] clk: hisilicon: Use devm_kcalloc() instead of devm_kzalloc()

[Erick Archer]

As noted in the "Deprecated Interfaces, Language Features, Attributes,
and Conventions" documentation [1], size calculations (especially
multiplication) should not be performed in memory allocator (or similar)
function arguments due to the risk of them overflowing. This could lead
to values wrapping around and a smaller allocation being made than the
caller was expecting. Using those allocations could lead to linear
overflows of heap memory and other misbehaviors.

So, use the purpose specific devm_kcalloc() function instead of the
argument size * count in the devm_kzalloc() function.

Link: https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1]
Link: https://github.com/KSPP/linux/issues/162
Signed-off-by: Erick Archer <erick.archer@gmx.com>
---
 drivers/clk/hisilicon/clk-hi3559a.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/clk/hisilicon/clk-hi3559a.c b/drivers/clk/hisilicon/clk-hi3559a.c
index ff4ca0edce06..da476f940326 100644
--- a/drivers/clk/hisilicon/clk-hi3559a.c
+++ b/drivers/clk/hisilicon/clk-hi3559a.c
@@ -461,8 +461,7 @@ static void hisi_clk_register_pll(struct hi3559av100_pll_clock *clks,
 	struct clk_init_data init;
 	int i;

-	p_clk = devm_kzalloc(dev, sizeof(*p_clk) * nums, GFP_KERNEL);
-
+	p_clk = devm_kcalloc(dev, nums, sizeof(*p_clk), GFP_KERNEL);
 	if (!p_clk)
 		return;

--
2.25.1

Re: [PATCH] clk: hisilicon: Use devm_kcalloc() instead of devm_kzalloc()

[Uwe Kleine-König]

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On Sun, Jan 21, 2024 at 03:29:46PM +0100, Erick Archer wrote:
> As noted in the "Deprecated Interfaces, Language Features, Attributes,
> and Conventions" documentation [1], size calculations (especially
> multiplication) should not be performed in memory allocator (or similar)
> function arguments due to the risk of them overflowing. This could lead
> to values wrapping around and a smaller allocation being made than the
> caller was expecting. Using those allocations could lead to linear
> overflows of heap memory and other misbehaviors.
> 
> So, use the purpose specific devm_kcalloc() function instead of the
> argument size * count in the devm_kzalloc() function.
> 
> Link: https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1]
> Link: https://github.com/KSPP/linux/issues/162
> Signed-off-by: Erick Archer <erick.archer@gmx.com>
> ---
>  drivers/clk/hisilicon/clk-hi3559a.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/clk/hisilicon/clk-hi3559a.c b/drivers/clk/hisilicon/clk-hi3559a.c
> index ff4ca0edce06..da476f940326 100644
> --- a/drivers/clk/hisilicon/clk-hi3559a.c
> +++ b/drivers/clk/hisilicon/clk-hi3559a.c
> @@ -461,8 +461,7 @@ static void hisi_clk_register_pll(struct hi3559av100_pll_clock *clks,
>  	struct clk_init_data init;
>  	int i;
> 
> -	p_clk = devm_kzalloc(dev, sizeof(*p_clk) * nums, GFP_KERNEL);
> -
> +	p_clk = devm_kcalloc(dev, nums, sizeof(*p_clk), GFP_KERNEL);
>  	if (!p_clk)
>  		return;

Looks good,

Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

My first impulse was to ask why hisi_clk_register_pll doesn't return an
error if the allocation fails, but I guess that happens so early that no
sensible error handling is possible?

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | https://www.pengutronix.de/ |

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Re: [PATCH] clk: hisilicon: Use devm_kcalloc() instead of devm_kzalloc()

[Gustavo A. R. Silva]

On 1/21/24 08:29, Erick Archer wrote:
> As noted in the "Deprecated Interfaces, Language Features, Attributes,
> and Conventions" documentation [1], size calculations (especially
> multiplication) should not be performed in memory allocator (or similar)
> function arguments due to the risk of them overflowing. This could lead
> to values wrapping around and a smaller allocation being made than the
> caller was expecting. Using those allocations could lead to linear
> overflows of heap memory and other misbehaviors.
> 
> So, use the purpose specific devm_kcalloc() function instead of the
> argument size * count in the devm_kzalloc() function.
> 
> Link: https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1]
> Link: https://github.com/KSPP/linux/issues/162
> Signed-off-by: Erick Archer <erick.archer@gmx.com>

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

Thanks!
-- 
Gustavo

> ---
>   drivers/clk/hisilicon/clk-hi3559a.c | 3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/clk/hisilicon/clk-hi3559a.c b/drivers/clk/hisilicon/clk-hi3559a.c
> index ff4ca0edce06..da476f940326 100644
> --- a/drivers/clk/hisilicon/clk-hi3559a.c
> +++ b/drivers/clk/hisilicon/clk-hi3559a.c
> @@ -461,8 +461,7 @@ static void hisi_clk_register_pll(struct hi3559av100_pll_clock *clks,
>   	struct clk_init_data init;
>   	int i;
> 
> -	p_clk = devm_kzalloc(dev, sizeof(*p_clk) * nums, GFP_KERNEL);
> -
> +	p_clk = devm_kcalloc(dev, nums, sizeof(*p_clk), GFP_KERNEL);
>   	if (!p_clk)
>   		return;
> 
> --
> 2.25.1
> 
> 

Re: [PATCH] clk: hisilicon: Use devm_kcalloc() instead of devm_kzalloc()

[Stephen Boyd]

Quoting Erick Archer (2024-01-21 06:29:46)
> As noted in the "Deprecated Interfaces, Language Features, Attributes,
> and Conventions" documentation [1], size calculations (especially
> multiplication) should not be performed in memory allocator (or similar)
> function arguments due to the risk of them overflowing. This could lead
> to values wrapping around and a smaller allocation being made than the
> caller was expecting. Using those allocations could lead to linear
> overflows of heap memory and other misbehaviors.
> 
> So, use the purpose specific devm_kcalloc() function instead of the
> argument size * count in the devm_kzalloc() function.
> 
> Link: https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1]
> Link: https://github.com/KSPP/linux/issues/162
> Signed-off-by: Erick Archer <erick.archer@gmx.com>
> ---

Applied to clk-next