Re: [Openvpn-devel] --with-mem-check, what to do with it?

[David S. <op...@sf...>]

On 29/12/17 12:02, Antonio Quartulli wrote:
> Hi,
> 
> On 29/12/17 18:23, Steffan Karger wrote:
>> Hi,
>>
>> On 29-12-17 11:11, Илья Шипицин wrote:
>>> thank for the patch.
>>>
>>> not directly related to the patch itself, but openvpn is shipped with
>>> several memory debugging options
>>>
>>> --with-mem-check=TYPE   build with debug memory checking
>>>
>>>
>>> should we get rid of them (in favour of sanitizers) ? or, maybe add to
>>> tests instead ?
>>
>> I've tried to use those in the past, but found them hard to use.  I
>> think they're a remnant of the past.  I would personally prefer to get
>> rid of them and use the (nowadays much better) fully external memory
>> checking tools instead (sanitizers, valgrind, etc).
> 
> As Selva pointed out, we don't use --with-mem-check in any test,
> therefore I am not even sure it still works as expected.
> 
> I am also in favour in of getting rid of our custom made check and use
> compilers provided sanitizers instead (also gcc provides interesting
> sanitizers, thus everybody should be bale to enable them).
> 
When compiling with --with-mem-check=valgrind ... a lot of the noise from
OpenSSL (and other external issues) vanishes when running OpenVPN via
valgrind.  So I find that feature very useful.  It's really handy to use this
approach when checking for memory leaks in plug-ins.

There might be better checks, granted.  But not sure how well they will play
with plug-ins.  The valgrind type works fine.  Not sure how well the other
--with-mem-check alternatives (dmalloc, ssl) works, so can't speak for them.
If they don't build or work, then we should consider to remove what doesn't work.


-- 
kind regards,

David Sommerseth
OpenVPN Inc