2011-12-03 08:20:59

by Thomas Meyer

Subject: [PATCH] rt2x00: Use kcalloc instead of kzalloc to allocate array

The advantage of kcalloc is, that will prevent integer overflows which could
result from the multiplication of number of elements and size and it is also
a bit nicer to read.

The semantic patch that makes this change is available
in https://lkml.org/lkml/2011/11/25/107

Signed-off-by: Thomas Meyer <[email protected]>
---

diff -u -p a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c
--- a/drivers/net/wireless/rt2x00/rt2x00dev.c 2011-11-28 19:36:47.770108588 +0100
+++ b/drivers/net/wireless/rt2x00/rt2x00dev.c 2011-11-28 19:54:53.495525543 +0100
@@ -831,11 +831,11 @@ static int rt2x00lib_probe_hw_modes(stru
if (spec->supported_rates & SUPPORT_RATE_OFDM)
num_rates += 8;

- channels = kzalloc(sizeof(*channels) * spec->num_channels, GFP_KERNEL);
+ channels = kcalloc(spec->num_channels, sizeof(*channels), GFP_KERNEL);
if (!channels)
return -ENOMEM;

- rates = kzalloc(sizeof(*rates) * num_rates, GFP_KERNEL);
+ rates = kcalloc(num_rates, sizeof(*rates), GFP_KERNEL);
if (!rates)
goto exit_free_channels;

2011-12-03 09:20:15

by Gertjan van Wingerde

Subject: Re: [PATCH] rt2x00: Use kcalloc instead of kzalloc to allocate array

On 29 nov. 2011, at 22:08, Thomas Meyer <[email protected]> wrote:

> The advantage of kcalloc is, that will prevent integer overflows which could
> result from the multiplication of number of elements and size and it is also
> a bit nicer to read.
>
> The semantic patch that makes this change is available
> in https://lkml.org/lkml/2011/11/25/107
>
> Signed-off-by: Thomas Meyer <[email protected]>

Acked-by: Gertjan van Wingerde <[email protected]>

> ---
>
> diff -u -p a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c
> --- a/drivers/net/wireless/rt2x00/rt2x00dev.c 2011-11-28 19:36:47.770108588 +0100
> +++ b/drivers/net/wireless/rt2x00/rt2x00dev.c 2011-11-28 19:54:53.495525543 +0100
> @@ -831,11 +831,11 @@ static int rt2x00lib_probe_hw_modes(stru
> if (spec->supported_rates & SUPPORT_RATE_OFDM)
> num_rates += 8;
>
> - channels = kzalloc(sizeof(*channels) * spec->num_channels, GFP_KERNEL);
> + channels = kcalloc(spec->num_channels, sizeof(*channels), GFP_KERNEL);
> if (!channels)
> return -ENOMEM;
>
> - rates = kzalloc(sizeof(*rates) * num_rates, GFP_KERNEL);
> + rates = kcalloc(num_rates, sizeof(*rates), GFP_KERNEL);
> if (!rates)
> goto exit_free_channels;
>

2011-12-03 11:46:16

by Ivo Van Doorn

Subject: Re: [PATCH] rt2x00: Use kcalloc instead of kzalloc to allocate array

On Tue, Nov 29, 2011 at 10:08 PM, Thomas Meyer <[email protected]> wrote:
> The advantage of kcalloc is, that will prevent integer overflows which could
> result from the multiplication of number of elements and size and it is also
> a bit nicer to read.
>
> The semantic patch that makes this change is available
> in https://lkml.org/lkml/2011/11/25/107
>
> Signed-off-by: Thomas Meyer <[email protected]>

Acked-by: Ivo van Doorn <[email protected]>

> ---
>
> diff -u -p a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c
> --- a/drivers/net/wireless/rt2x00/rt2x00dev.c 2011-11-28 19:36:47.770108588 +0100
> +++ b/drivers/net/wireless/rt2x00/rt2x00dev.c 2011-11-28 19:54:53.495525543 +0100
> @@ -831,11 +831,11 @@ static int rt2x00lib_probe_hw_modes(stru
> ? ? ? ?if (spec->supported_rates & SUPPORT_RATE_OFDM)
> ? ? ? ? ? ? ? ?num_rates += 8;
>
> - ? ? ? channels = kzalloc(sizeof(*channels) * spec->num_channels, GFP_KERNEL);
> + ? ? ? channels = kcalloc(spec->num_channels, sizeof(*channels), GFP_KERNEL);
> ? ? ? ?if (!channels)
> ? ? ? ? ? ? ? ?return -ENOMEM;
>
> - ? ? ? rates = kzalloc(sizeof(*rates) * num_rates, GFP_KERNEL);
> + ? ? ? rates = kcalloc(num_rates, sizeof(*rates), GFP_KERNEL);
> ? ? ? ?if (!rates)
> ? ? ? ? ? ? ? ?goto exit_free_channels;
>