[PATCH] MIPS: Alchemy: Use kcalloc() instead of kzalloc()

[PATCH] MIPS: Alchemy: Use kcalloc() instead of 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 kcalloc() function instead of the argument
size * count in the 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>
---
 arch/mips/alchemy/common/clock.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/mips/alchemy/common/clock.c b/arch/mips/alchemy/common/clock.c
index c01be8c45271..6c8996e20a7d 100644
--- a/arch/mips/alchemy/common/clock.c
+++ b/arch/mips/alchemy/common/clock.c
@@ -771,7 +771,7 @@ static int __init alchemy_clk_init_fgens(int ctype)
 	}
 	id.flags = CLK_SET_RATE_PARENT | CLK_GET_RATE_NOCACHE;

-	a = kzalloc((sizeof(*a)) * 6, GFP_KERNEL);
+	a = kcalloc(6, sizeof(*a), GFP_KERNEL);
 	if (!a)
 		return -ENOMEM;

--
2.25.1

Re: [PATCH] MIPS: Alchemy: Use kcalloc() instead of kzalloc()

[Gustavo A. R. Silva]

On 1/20/24 07:34, 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 kcalloc() function instead of the argument
> size * count in the 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

> ---
>   arch/mips/alchemy/common/clock.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/mips/alchemy/common/clock.c b/arch/mips/alchemy/common/clock.c
> index c01be8c45271..6c8996e20a7d 100644
> --- a/arch/mips/alchemy/common/clock.c
> +++ b/arch/mips/alchemy/common/clock.c
> @@ -771,7 +771,7 @@ static int __init alchemy_clk_init_fgens(int ctype)
>   	}
>   	id.flags = CLK_SET_RATE_PARENT | CLK_GET_RATE_NOCACHE;
> 
> -	a = kzalloc((sizeof(*a)) * 6, GFP_KERNEL);
> +	a = kcalloc(6, sizeof(*a), GFP_KERNEL);
>   	if (!a)
>   		return -ENOMEM;
> 
> --
> 2.25.1
> 
> 

Re: [PATCH] MIPS: Alchemy: Use kcalloc() instead of kzalloc()

[Thomas Bogendoerfer]

On Sat, Jan 20, 2024 at 02:34:43PM +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 kcalloc() function instead of the argument
> size * count in the 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>
> ---
>  arch/mips/alchemy/common/clock.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/mips/alchemy/common/clock.c b/arch/mips/alchemy/common/clock.c
> index c01be8c45271..6c8996e20a7d 100644
> --- a/arch/mips/alchemy/common/clock.c
> +++ b/arch/mips/alchemy/common/clock.c
> @@ -771,7 +771,7 @@ static int __init alchemy_clk_init_fgens(int ctype)
>  	}
>  	id.flags = CLK_SET_RATE_PARENT | CLK_GET_RATE_NOCACHE;
> 
> -	a = kzalloc((sizeof(*a)) * 6, GFP_KERNEL);
> +	a = kcalloc(6, sizeof(*a), GFP_KERNEL);
>  	if (!a)
>  		return -ENOMEM;
> 
> --
> 2.25.1

applied to mips-next.

Thomas.

-- 
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea.                                                [ RFC1925, 2.3 ]