From 208dea486fa24081cbc0cf05fa5a15c802e2bc68 Mon Sep 17 00:00:00 2001

From: John Lightsey <jd@cpanel.net>

Date: Wed, 20 Nov 2019 20:02:45 -0600

Subject: [PATCH v528 1/3] regcomp.c: Prevent integer overflow from nested

 regex quantifiers.

(CVE-2020-10543) On 32bit systems the size calculations for nested regular

expression quantifiers could overflow causing heap memory corruption.

Fixes: Perl/perl5-security#125

---

 regcomp.c | 6 ++++++

 1 file changed, 6 insertions(+)

diff --git a/regcomp.c b/regcomp.c

index e1da15a77c..dd18add1db 100644

--- a/regcomp.c

+++ b/regcomp.c

@@ -5102,6 +5139,12 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,

 		    (void)ReREFCNT_inc(RExC_rx_sv);

 		}

+                if ( ( minnext > 0 && mincount >= SSize_t_MAX / minnext )

+                    || min >= SSize_t_MAX - minnext * mincount )

+                {

+                    FAIL("Regexp out of space");

+                }

+

 		min += minnext * mincount;

 		is_inf_internal |= deltanext == SSize_t_MAX

                          || (maxcount == REG_INFTY && minnext + deltanext > 0);

-- 

2.20.1