Fix possible out-of-bounds array access

If match is "", match[-1] is accessed.  Let pathspec_matches return 1 in that
case indicating that "" matches everything.

Incidently this fixes git-grep'ing in ".".

Signed-off-by: Uwe Zeisberger <Uwe_Zeisberger@digi.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/builtin-grep.c b/builtin-grep.c
index 9806499263dcb92c7a6903ead36646baf676b178..f7767bb4eeacf4d4c06ef54e6bb3f4099e96d198 100644 (file)
--- a/builtin-grep.c
+++ b/builtin-grep.c
@@ -29,10 +29,11 @@ static int pathspec_matches(const char **paths, const char *name)
                int matchlen = strlen(match);
                const char *cp, *meta;
 
-               if ((matchlen <= namelen) &&
-                   !strncmp(name, match, matchlen) &&
-                   (match[matchlen-1] == '/' ||
-                    name[matchlen] == '\0' || name[matchlen] == '/'))
+               if (!matchlen ||
+                   ((matchlen <= namelen) &&
+                    !strncmp(name, match, matchlen) &&
+                    (match[matchlen-1] == '/' ||
+                     name[matchlen] == '\0' || name[matchlen] == '/')))
                        return 1;
                if (!fnmatch(match, name, 0))
                        return 1;