[Lcdproc] [PATCH] Memory leaks / NULL pointer dereference on malloc() failure in widget.c

[Andre Guibert de Bruet]

On Dec 14, 2008, at 5:05 AM, Peter Marschall wrote:

> On Saturday, 13. December 2008, Andre Guibert de Bruet wrote:
>> I came across a couple of problems in widget_create(). On a system
>> with sufficient memory (Common case scenario), the function works as
>> expected. Under tight memory conditions, the function doesn't fare so
>> well:
>>
>> * When strdup() fails the allocation of w->id, the function returns
>> NULL. We previously allocated w, which doesn't get free()'ed before
>> the return statement.
>>
>> * frame_name is used without checking if the returned pointer is  
>> NULL.
>> My fix adds a debug report() call, the freeing of w->id and w, as  
>> well
>> as causing the function to return NULL, much like the other  
>> allocation
>> failures.
>>
>> Could you commit the attached patch upon review?
>
> Yepp.
> Thanks for the patch.
>
> I found another leak in widget_create,which I plugged as well.
> In addition to  that I reset free()'d pointers to NULL in
> widget_destroy() and documented the methods with Doxygen.
>
> To make it more complete I did the same in server/screen.c
>
> Please test.


Looks good except for one tiny change in screen.c (See attached patch).

Cheers,

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