2024-01-19 18:19:49

by Erick Archer

[permalink] [raw]
Subject: [PATCH] pinctrl: pinctrl-zynqmp: Use devm_kcalloc() instead of devm_kzalloc()

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 <[email protected]>
---
drivers/pinctrl/pinctrl-zynqmp.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-zynqmp.c b/drivers/pinctrl/pinctrl-zynqmp.c
index f2be341f73e1..5c46b7d7ebcb 100644
--- a/drivers/pinctrl/pinctrl-zynqmp.c
+++ b/drivers/pinctrl/pinctrl-zynqmp.c
@@ -562,7 +562,7 @@ static int zynqmp_pinctrl_prepare_func_groups(struct device *dev, u32 fid,
const char **fgroups;
int ret, index, i;

- fgroups = devm_kzalloc(dev, sizeof(*fgroups) * func->ngroups, GFP_KERNEL);
+ fgroups = devm_kcalloc(dev, func->ngroups, sizeof(*fgroups), GFP_KERNEL);
if (!fgroups)
return -ENOMEM;

@@ -754,7 +754,7 @@ static int zynqmp_pinctrl_prepare_function_info(struct device *dev,
if (ret)
return ret;

- funcs = devm_kzalloc(dev, sizeof(*funcs) * pctrl->nfuncs, GFP_KERNEL);
+ funcs = devm_kcalloc(dev, pctrl->nfuncs, sizeof(*funcs), GFP_KERNEL);
if (!funcs)
return -ENOMEM;

@@ -768,7 +768,7 @@ static int zynqmp_pinctrl_prepare_function_info(struct device *dev,
pctrl->ngroups += funcs[i].ngroups;
}

- groups = devm_kzalloc(dev, sizeof(*groups) * pctrl->ngroups, GFP_KERNEL);
+ groups = devm_kcalloc(dev, pctrl->ngroups, sizeof(*groups), GFP_KERNEL);
if (!groups)
return -ENOMEM;

@@ -830,7 +830,7 @@ static int zynqmp_pinctrl_prepare_pin_desc(struct device *dev,
if (ret)
return ret;

- pins = devm_kzalloc(dev, sizeof(*pins) * *npins, GFP_KERNEL);
+ pins = devm_kcalloc(dev, *npins, sizeof(*pins), GFP_KERNEL);
if (!pins)
return -ENOMEM;

--
2.25.1



2024-01-19 18:28:17

by Gustavo A. R. Silva

[permalink] [raw]
Subject: Re: [PATCH] pinctrl: pinctrl-zynqmp: Use devm_kcalloc() instead of devm_kzalloc()



On 1/19/24 12:19, 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 <[email protected]>

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

Thanks!
--
Gustavo

> ---
> drivers/pinctrl/pinctrl-zynqmp.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/pinctrl/pinctrl-zynqmp.c b/drivers/pinctrl/pinctrl-zynqmp.c
> index f2be341f73e1..5c46b7d7ebcb 100644
> --- a/drivers/pinctrl/pinctrl-zynqmp.c
> +++ b/drivers/pinctrl/pinctrl-zynqmp.c
> @@ -562,7 +562,7 @@ static int zynqmp_pinctrl_prepare_func_groups(struct device *dev, u32 fid,
> const char **fgroups;
> int ret, index, i;
>
> - fgroups = devm_kzalloc(dev, sizeof(*fgroups) * func->ngroups, GFP_KERNEL);
> + fgroups = devm_kcalloc(dev, func->ngroups, sizeof(*fgroups), GFP_KERNEL);
> if (!fgroups)
> return -ENOMEM;
>
> @@ -754,7 +754,7 @@ static int zynqmp_pinctrl_prepare_function_info(struct device *dev,
> if (ret)
> return ret;
>
> - funcs = devm_kzalloc(dev, sizeof(*funcs) * pctrl->nfuncs, GFP_KERNEL);
> + funcs = devm_kcalloc(dev, pctrl->nfuncs, sizeof(*funcs), GFP_KERNEL);
> if (!funcs)
> return -ENOMEM;
>
> @@ -768,7 +768,7 @@ static int zynqmp_pinctrl_prepare_function_info(struct device *dev,
> pctrl->ngroups += funcs[i].ngroups;
> }
>
> - groups = devm_kzalloc(dev, sizeof(*groups) * pctrl->ngroups, GFP_KERNEL);
> + groups = devm_kcalloc(dev, pctrl->ngroups, sizeof(*groups), GFP_KERNEL);
> if (!groups)
> return -ENOMEM;
>
> @@ -830,7 +830,7 @@ static int zynqmp_pinctrl_prepare_pin_desc(struct device *dev,
> if (ret)
> return ret;
>
> - pins = devm_kzalloc(dev, sizeof(*pins) * *npins, GFP_KERNEL);
> + pins = devm_kcalloc(dev, *npins, sizeof(*pins), GFP_KERNEL);
> if (!pins)
> return -ENOMEM;
>
> --
> 2.25.1
>
>

2024-01-22 06:56:06

by Michal Simek

[permalink] [raw]
Subject: Re: [PATCH] pinctrl: pinctrl-zynqmp: Use devm_kcalloc() instead of devm_kzalloc()



On 1/19/24 19:19, 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 <[email protected]>
> ---
> drivers/pinctrl/pinctrl-zynqmp.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/pinctrl/pinctrl-zynqmp.c b/drivers/pinctrl/pinctrl-zynqmp.c
> index f2be341f73e1..5c46b7d7ebcb 100644
> --- a/drivers/pinctrl/pinctrl-zynqmp.c
> +++ b/drivers/pinctrl/pinctrl-zynqmp.c
> @@ -562,7 +562,7 @@ static int zynqmp_pinctrl_prepare_func_groups(struct device *dev, u32 fid,
> const char **fgroups;
> int ret, index, i;
>
> - fgroups = devm_kzalloc(dev, sizeof(*fgroups) * func->ngroups, GFP_KERNEL);
> + fgroups = devm_kcalloc(dev, func->ngroups, sizeof(*fgroups), GFP_KERNEL);
> if (!fgroups)
> return -ENOMEM;
>
> @@ -754,7 +754,7 @@ static int zynqmp_pinctrl_prepare_function_info(struct device *dev,
> if (ret)
> return ret;
>
> - funcs = devm_kzalloc(dev, sizeof(*funcs) * pctrl->nfuncs, GFP_KERNEL);
> + funcs = devm_kcalloc(dev, pctrl->nfuncs, sizeof(*funcs), GFP_KERNEL);
> if (!funcs)
> return -ENOMEM;
>
> @@ -768,7 +768,7 @@ static int zynqmp_pinctrl_prepare_function_info(struct device *dev,
> pctrl->ngroups += funcs[i].ngroups;
> }
>
> - groups = devm_kzalloc(dev, sizeof(*groups) * pctrl->ngroups, GFP_KERNEL);
> + groups = devm_kcalloc(dev, pctrl->ngroups, sizeof(*groups), GFP_KERNEL);
> if (!groups)
> return -ENOMEM;
>
> @@ -830,7 +830,7 @@ static int zynqmp_pinctrl_prepare_pin_desc(struct device *dev,
> if (ret)
> return ret;
>
> - pins = devm_kzalloc(dev, sizeof(*pins) * *npins, GFP_KERNEL);
> + pins = devm_kcalloc(dev, *npins, sizeof(*pins), GFP_KERNEL);
> if (!pins)
> return -ENOMEM;
>
> --
> 2.25.1
>

Acked-by: Michal Simek <[email protected]>

Thanks,
Michal

2024-01-28 00:18:22

by Linus Walleij

[permalink] [raw]
Subject: Re: [PATCH] pinctrl: pinctrl-zynqmp: Use devm_kcalloc() instead of devm_kzalloc()

On Fri, Jan 19, 2024 at 7:19 PM Erick Archer <[email protected]> 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 <[email protected]>

Patch applied!

Yours,
Linus Walleij