Re: [dpdk-dev] [PATCH 1/2] crypto/scheduler: set null pointer after freeing

[Akhil Goyal <akhil.goyal@nxp.com>]

Hi Pablo,

On 4/27/2018 5:06 PM, De Lara Guarch, Pablo wrote:
> Hi Akhil,
>
>> -----Original Message-----
>> From: Akhil Goyal [mailto:akhil.goyal@nxp.com]
>> Sent: Friday, April 27, 2018 9:47 AM
>> To: De Lara Guarch, Pablo <pablo.de.lara.guarch@intel.com>; Zhang, Roy Fan
>> <roy.fan.zhang@intel.com>
>> Cc: dev@dpdk.org; stable@dpdk.org
>> Subject: Re: [dpdk-dev] [PATCH 1/2] crypto/scheduler: set null pointer after
>> freeing
>>
>> Hi Pablo,
>>
>> On 4/26/2018 8:39 PM, Pablo de Lara wrote:
>>> When freeing memory, pointers should be set to NULL, to avoid memory
>>> corruption/segmentation faults.
>>
>> Shouldn't this be handled in the rte_free itself. A lot of other driver are also not
>> setting null after rte_free.
>> This would require change at a lot of places if this is not handled in rte_free.
>>
>
> The glibc function "free" works the same way. Users are responsible for
> setting to NULL these pointers (because sometimes, it is not necessary to do such thing).
Yes it is correct but rte_free is custom free API in DPDK which can be 
modified or we can have a safer API rte_free_safe which can set the 
pointer to null.
>
> Anyway, in case we still wanted to change it, we would need to pass a pointer
> to a pointer in rte_free, which would imply an API breakage.
>
I think if the community agrees, we can add this change may be in next 
releases.

> Thanks,
> Pablo
>
>> Thanks,
>> Akhil