for-each-ref: fix segfault in copy_email

You can trigger a segfault in git.git by doing: git for-each-ref --format='%(taggeremail)' refs/tags/v0.99 The v0.99 tag is special in that it contains no "tagger" header. The bug is obvious in copy_email, which carefully checks to make sure the result of a strchr is non-NULL, but only after already having used it to perform other work. The fix is to move the check up. Signed-off-by: Jeff King <[email protected]> Signed-off-by: Junio C Hamano <[email protected]>
luceliu · May 20, 2009 · e64c1b0 · e64c1b0
1 parent 5acb3e5
commit e64c1b0
Showing 1 changed file with 5 additions and 2 deletions.
diff --git a/builtin-for-each-ref.c b/builtin-for-each-ref.c
@@ -339,8 +339,11 @@ static const char *copy_name(const char *buf)
 static const char *copy_email(const char *buf)
 {
 	const char *email = strchr(buf, '<');
-	const char *eoemail = strchr(email, '>');
-	if (!email || !eoemail)
+	const char *eoemail;
+	if (!email)
+		return "";
+	eoemail = strchr(email, '>');
+	if (!eoemail)
 		return "";
 	return xmemdupz(email, eoemail + 1 - email);
 }