From afd7a21d11854ec1510b5ab4430f4f4c5dc7377c Mon Sep 17 00:00:00 2001
From: Alexey Zelkin <phantom@freebsd10-amd64-phantom.gnt.nginx.com>
Date: Tue, 5 Jul 2016 09:32:29 +0000
Subject: [PATCH] Correctly handle return values from pcre_study(3)

If both function's return value and errptr are NULLs, it means
that pcre_study() does not make sense, so can be ignored.
---
 src/operators/verify_cc.cc | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/operators/verify_cc.cc b/src/operators/verify_cc.cc
index 88ad55e4..f7b46577 100644
--- a/src/operators/verify_cc.cc
+++ b/src/operators/verify_cc.cc
@@ -85,9 +85,20 @@ bool VerifyCC::init(const std::string &param2, std::string *error) {
 
     m_pc = pcre_compile(param.c_str(), PCRE_DOTALL|PCRE_MULTILINE,
         &errptr, &erroffset, NULL);
-    m_pce = pcre_study(m_pc, PCRE_STUDY_JIT_COMPILE, &errptr);
+    if (m_pc == NULL) {
+        error->assign(errptr);
+        return false;
+    }
 
-    if ((m_pc == NULL) || (m_pce == NULL)) {
+    m_pce = pcre_study(m_pc, PCRE_STUDY_JIT_COMPILE, &errptr);
+    if (m_pce == NULL) {
+        if (errptr == NULL) {
+            /*
+             * Per pcre_study(3) m_pce == NULL && errptr == NULL means
+             * that no addional information is found, so no need to study
+             */
+            return true;
+        }
         error->assign(errptr);
         return false;
     }