Merge branch 'jk/head-symref'

* jk/head-symref:
  symbolic ref: refuse non-ref targets in HEAD
  validate_headref: tighten ref-matching to just branches

3 files changed, 46 insertions, 2 deletions

diff --git a/builtin-symbolic-ref.c b/builtin-symbolic-ref.c
index bfc78bb3f6..cafc4eba7c 100644
--- a/builtin-symbolic-ref.c
+++ b/builtin-symbolic-ref.c
@@ -44,6 +44,9 @@ int cmd_symbolic_ref(int argc, const char **argv, const char *prefix)
 		check_symref(argv[0], quiet);
 		break;
 	case 2:
+		if (!strcmp(argv[0], "HEAD") &&
+		    prefixcmp(argv[1], "refs/heads/"))
+			die("Refusing to point HEAD outside of refs/heads/");
 		create_symref(argv[0], argv[1], msg);
 		break;
 	default:
diff --git a/path.c b/path.c
index a074aea649..108d9e9599 100644
--- a/path.c
+++ b/path.c
@@ -154,7 +154,7 @@ int validate_headref(const char *path)
 	/* Make sure it is a "refs/.." symlink */
 	if (S_ISLNK(st.st_mode)) {
 		len = readlink(path, buffer, sizeof(buffer)-1);
-		if (len >= 5 && !memcmp("refs/", buffer, 5))
+		if (len >= 11 && !memcmp("refs/heads/", buffer, 11))
 			return 0;
 		return -1;
 	}
@@ -178,7 +178,7 @@ int validate_headref(const char *path)
 		len -= 4;
 		while (len && isspace(*buf))
 			buf++, len--;
-		if (len >= 5 && !memcmp("refs/", buf, 5))
+		if (len >= 11 && !memcmp("refs/heads/", buf, 11))
 			return 0;
 	}
 
diff --git a/t/t1401-symbolic-ref.sh b/t/t1401-symbolic-ref.sh
new file mode 100755
index 0000000000..569f34177d
--- /dev/null
+++ b/t/t1401-symbolic-ref.sh
@@ -0,0 +1,41 @@
+#!/bin/sh
+
+test_description='basic symbolic-ref tests'
+. ./test-lib.sh
+
+# If the tests munging HEAD fail, they can break detection of
+# the git repo, meaning that further tests will operate on
+# the surrounding git repo instead of the trash directory.
+reset_to_sane() {
+	echo ref: refs/heads/foo >.git/HEAD
+}
+
+test_expect_success 'symbolic-ref writes HEAD' '
+	git symbolic-ref HEAD refs/heads/foo &&
+	echo ref: refs/heads/foo >expect &&
+	test_cmp expect .git/HEAD
+'
+
+test_expect_success 'symbolic-ref reads HEAD' '
+	echo refs/heads/foo >expect &&
+	git symbolic-ref HEAD >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'symbolic-ref refuses non-ref for HEAD' '
+	test_must_fail git symbolic-ref HEAD foo
+'
+reset_to_sane
+
+test_expect_success 'symbolic-ref refuses non-branch for HEAD' '
+	test_must_fail git symbolic-ref HEAD refs/foo
+'
+reset_to_sane
+
+test_expect_success 'symbolic-ref refuses bare sha1' '
+	echo content >file && git add file && git commit -m one
+	test_must_fail git symbolic-ref HEAD `git rev-parse HEAD`
+'
+reset_to_sane
+
+test_done