Re: [PATCH] ipc,sem block sem_lock on sma->lock during sma initialization

From: Rik van Riel
Date: Sat Nov 22 2014 - 10:54:26 EST


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On 11/22/2014 08:56 AM, Manfred Spraul wrote:
> Hi Rik,
>
> good catch - I completely forgot to check the initialization
>
> On 11/22/2014 04:40 AM, Rik van Riel wrote:
>>
>> newary initializes a bunch of things after the call to ipc_addid,
>> however some things are initialized inside ipc_addid as well
>>
>> Looking closer at newary, I suppose that it should be possible to
>> move those other initializations before the call to ipc_addid.
>> That would likely get rid of the problem, too.
>>
>> However, I also see this line in newary, and I have no idea what
>> protects that data:
>>
>> ns->used_sems += nsems;
> It should be sem_ids.rwsem, and at least according to the
> documentation both freeary() and newary() hold it.

You're right, that is properly protected already.

- --
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