[libvirt PATCH 0/3] Reduce stack frame size of virNWFilterRuleDefFixup

[Daniel P. Berrangé]

On Fri, Sep 17, 2021 at 03:37:28PM +0200, Tim Wiederhake wrote:
> On Fri, 2021-09-17 at 14:10 +0100, Daniel P. Berrangé wrote:
> > On Fri, Sep 17, 2021 at 02:58:08PM +0200, Tim Wiederhake wrote:
> > > When libvirt is build with sanitizers enabled, in debug mode, on
> > > clang,
> > > virNWFilterRuleDefFixup exceeds the maximum stack frame size of
> > > 8192 bytes,
> > > as specified in meson.build:
> > > 
> > >   ../src/conf/nwfilter_conf.c:2190:1: error: stack frame size of
> > > 10616
> > >   bytes in function 'virNWFilterRuleDefFixup' [-Werror,-Wframe-
> > > larger-than=]
> > >   virNWFilterRuleDefFixup(virNWFilterRuleDef *rule)
> > >   ^
> > >   1 error generated.
> > > 
> > > This series reworks the function a bit to bring the frame size
> > > below 8192.
> > 
> > Why don't we just enlarge stack size limit for building with
> > sanitizers ?
> > 
> > 
> > Regards,
> > Daniel
> 
> We already double the stack size limit for debug builds, and increasing
> it further seemed excessive.
> 
> Note that there is one more function that exceeds the limit,
> virDomainDefParseXML, for which I have a patch ready. I will send it
> once this series lands.

We're not using sanitizers in production builds though, so IMHO we could
even just run with no stack size checking entirely for such builds.

Regards,
Daniel
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