Avoid use of a potentially overflowing buffer in pcregrep.

git-svn-id: svn://vcs.exim.org/pcre/code/trunk@1684 2f5784b3-3f2a-0410-8824-cb99058d5e15

2 files changed, 8 insertions, 3 deletions

diff --git a/ChangeLog b/ChangeLog
index cac3973..019e0f5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -20,6 +20,9 @@ several lines after the start.
 4.  A (?# style comment is now ignored between a basic quantifier and a 
 following '+' or '?' (example: /X+(?#comment)?Y/.
 
+5.  Avoid use of a potentially overflowing buffer in pcregrep (patch by Petr 
+Pisar).
+
 
 Version 8.40 11-January-2017
 ----------------------------
diff --git a/pcregrep.c b/pcregrep.c
index 3cd70ee..87a3c2e 100644
--- a/pcregrep.c
+++ b/pcregrep.c
@@ -3190,9 +3190,11 @@ for (j = 1, cp = patterns; cp != NULL; j++, cp = cp->next)
   cp->hint = pcre_study(cp->compiled, study_options, &error);
   if (error != NULL)
     {
-    char s[16];
-    if (patterns->next == NULL) s[0] = 0; else sprintf(s, " number %d", j);
-    fprintf(stderr, "pcregrep: Error while studying regex%s: %s\n", s, error);
+    if (patterns->next == NULL)
+      fprintf(stderr, "pcregrep: Error while studying regex: %s\n", error);
+    else
+      fprintf(stderr, "pcregrep: Error while studying regex number %d: %s\n",
+        j, error);
     goto EXIT2;
     }
 #ifdef SUPPORT_PCREGREP_JIT