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[perl #134266] stack-overflow (can't grow stack) inPerl_sv_vcatpvfn_flags

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From:
Tony Cook via RT
Date:
August 5, 2019 01:46
Subject:
[perl #134266] stack-overflow (can't grow stack) inPerl_sv_vcatpvfn_flags
Message ID:
rt-4.0.24-21187-1564969587-1317.134266-15-0@perl.org
On Mon, 08 Jul 2019 02:03:17 -0700, davem wrote:
> On Fri, Jul 05, 2019 at 09:45:28PM -0700, Nguyen Duc Manh wrote:
> > root@instance-2:~# cat test.pl
> > eval '"a" =~ /${*@=\_})/';
> > root@instance-2:~# ./perl/perl test.pl
> > Segmentation fault
> 
> This code is making $@ an alias of the read-only constant string "_".
> Then corak during regexp compilation. The croaking tries to update $@,
> which croaks because it is read-only, and so infinitely recurses.
> 
> I can't see that its a security issue.

Agreed, now public.

Tony

---
via perlbug:  queue: perl5 status: open
https://rt.perl.org/Ticket/Display.html?id=134266

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