Add memCHRs() macro and use it

This replaces strchr("list", c) calls throughout the core.  They don't
work properly when 'c' is a NUL, returning the position of the
terminating NUL in "list" instead of failure.  This could lead to
segfaults or even security issues.

1 files changed, 2 insertions, 2 deletions

diff --git a/util.c b/util.c
index 861633ea31..0321a6ae92 100644
--- a/util.c
+++ b/util.c
@@ -4941,7 +4941,7 @@ Perl_quadmath_format_valid(const char* format)
         return FALSE;
     len = strlen(format);
     /* minimum length three: %Qg */
-    if (len < 3 || strchr("efgaEFGA", format[len - 1]) == NULL)
+    if (len < 3 || memCHRs("efgaEFGA", format[len - 1]) == NULL)
         return FALSE;
     if (format[len - 2] != 'Q')
         return FALSE;
@@ -4998,7 +4998,7 @@ Perl_quadmath_format_needed(const char* format)
       else
         while (isDIGIT(*q)) q++;
     }
-    if (strchr("efgaEFGA", *q)) /* Would have needed 'Q' in front. */
+    if (memCHRs("efgaEFGA", *q)) /* Would have needed 'Q' in front. */
       return TRUE;
     p = q + 1;
   }