Merge branch 'tr/maint-apply-non-git-patch-parsefix' into maint

"git apply" parsed patches that add new files, generated by programs
other than Git, incorrectly.  This is an old breakage in v1.7.11.

* tr/maint-apply-non-git-patch-parsefix:
  apply: carefully strdup a possibly-NULL name

Author: gitster

builtin/apply.c

@@ -906,7 +906,7 @@ static void parse_traditional_patch(const char *first, const char *second, struc
 			patch->old_name = name;
 		} else {
 			patch->old_name = name;
-			patch->new_name = xstrdup(name);
+			patch->new_name = null_strdup(name);
 		}
 	}
 	if (!name)

t/t4111-apply-subdir.sh

@@ -86,6 +86,20 @@ test_expect_success 'apply --index from subdir of toplevel' '
 	test_cmp expected sub/dir/file
 '
 
+test_expect_success 'apply half-broken patch from subdir of toplevel' '
+	(
+		cd sub/dir &&
+		test_must_fail git apply <<-EOF
+		--- sub/dir/file
+		+++ sub/dir/file
+		@@ -1,0 +1,0 @@
+		--- file_in_root
+		+++ file_in_root
+		@@ -1,0 +1,0 @@
+		EOF
+	)
+'
+
 test_expect_success 'apply from .git dir' '
 	cp postimage expected &&
 	cp preimage .git/file &&