diff --git a/builtin/fsck.c b/builtin/fsck.c
index d42a27da89..0928a98a71 100644
--- a/builtin/fsck.c
+++ b/builtin/fsck.c
@@ -388,7 +388,8 @@ static void fsck_sha1_list(void)
 		unsigned char *sha1 = entry->sha1;
 
 		sha1_list.entry[i] = NULL;
-		fsck_sha1(sha1);
+		if (fsck_sha1(sha1))
+			errors_found |= ERROR_OBJECT;
 		free(entry);
 	}
 	sha1_list.nr = 0;
@@ -488,6 +489,7 @@ static int fsck_handle_ref(const char *refname, const unsigned char *sha1, int f
 	obj = parse_object(sha1);
 	if (!obj) {
 		error("%s: invalid sha1 pointer %s", refname, sha1_to_hex(sha1));
+		errors_found |= ERROR_REACHABLE;
 		/* We'll continue with the rest despite the error.. */
 		return 0;
 	}
@@ -504,7 +506,7 @@ static void get_default_heads(void)
 {
 	if (head_points_at && !is_null_sha1(head_sha1))
 		fsck_handle_ref("HEAD", head_sha1, 0, NULL);
-	for_each_ref(fsck_handle_ref, NULL);
+	for_each_rawref(fsck_handle_ref, NULL);
 	if (include_reflogs)
 		for_each_reflog(fsck_handle_reflog, NULL);
 
diff --git a/t/t1450-fsck.sh b/t/t1450-fsck.sh
index 8c739c9613..b52397afd3 100755
--- a/t/t1450-fsck.sh
+++ b/t/t1450-fsck.sh
@@ -69,7 +69,7 @@ test_expect_success 'object with bad sha1' '
 	git update-ref refs/heads/bogus $cmt &&
 	test_when_finished "git update-ref -d refs/heads/bogus" &&
 
-	test_might_fail git fsck 2>out &&
+	test_must_fail git fsck 2>out &&
 	cat out &&
 	grep "$sha.*corrupt" out
 '
@@ -101,7 +101,7 @@ test_expect_success 'email with embedded > is not okay' '
 	test_when_finished "remove_object $new" &&
 	git update-ref refs/heads/bogus "$new" &&
 	test_when_finished "git update-ref -d refs/heads/bogus" &&
-	git fsck 2>out &&
+	test_must_fail git fsck 2>out &&
 	cat out &&
 	grep "error in commit $new" out
 '
@@ -113,7 +113,7 @@ test_expect_success 'missing < email delimiter is reported nicely' '
 	test_when_finished "remove_object $new" &&
 	git update-ref refs/heads/bogus "$new" &&
 	test_when_finished "git update-ref -d refs/heads/bogus" &&
-	git fsck 2>out &&
+	test_must_fail git fsck 2>out &&
 	cat out &&
 	grep "error in commit $new.* - bad name" out
 '
@@ -125,7 +125,7 @@ test_expect_success 'missing email is reported nicely' '
 	test_when_finished "remove_object $new" &&
 	git update-ref refs/heads/bogus "$new" &&
 	test_when_finished "git update-ref -d refs/heads/bogus" &&
-	git fsck 2>out &&
+	test_must_fail git fsck 2>out &&
 	cat out &&
 	grep "error in commit $new.* - missing email" out
 '
@@ -137,7 +137,7 @@ test_expect_success '> in name is reported' '
 	test_when_finished "remove_object $new" &&
 	git update-ref refs/heads/bogus "$new" &&
 	test_when_finished "git update-ref -d refs/heads/bogus" &&
-	git fsck 2>out &&
+	test_must_fail git fsck 2>out &&
 	cat out &&
 	grep "error in commit $new" out
 '
@@ -151,11 +151,31 @@ test_expect_success 'integer overflow in timestamps is reported' '
 	test_when_finished "remove_object $new" &&
 	git update-ref refs/heads/bogus "$new" &&
 	test_when_finished "git update-ref -d refs/heads/bogus" &&
-	git fsck 2>out &&
+	test_must_fail git fsck 2>out &&
 	cat out &&
 	grep "error in commit $new.*integer overflow" out
 '
 
+test_expect_success 'malformatted tree object' '
+	test_when_finished "git update-ref -d refs/tags/wrong" &&
+	test_when_finished "remove_object \$T" &&
+	T=$(
+		GIT_INDEX_FILE=test-index &&
+		export GIT_INDEX_FILE &&
+		rm -f test-index &&
+		>x &&
+		git add x &&
+		T=$(git write-tree) &&
+		(
+			git cat-file tree $T &&
+			git cat-file tree $T
+		) |
+		git hash-object -w -t tree --stdin
+	) &&
+	test_must_fail git fsck 2>out &&
+	grep "error in tree .*contains duplicate file entries" out
+'
+
 test_expect_success 'tag pointing to nonexistent' '
 	cat >invalid-tag <<-\EOF &&
 	object ffffffffffffffffffffffffffffffffffffffff
@@ -282,4 +302,60 @@ test_expect_success 'fsck notices ".git" in trees' '
 	)
 '
 
+# create a static test repo which is broken by omitting
+# one particular object ($1, which is looked up via rev-parse
+# in the new repository).
+create_repo_missing () {
+	rm -rf missing &&
+	git init missing &&
+	(
+		cd missing &&
+		git commit -m one --allow-empty &&
+		mkdir subdir &&
+		echo content >subdir/file &&
+		git add subdir/file &&
+		git commit -m two &&
+		unrelated=$(echo unrelated | git hash-object --stdin -w) &&
+		git tag -m foo tag $unrelated &&
+		sha1=$(git rev-parse --verify "$1") &&
+		path=$(echo $sha1 | sed 's|..|&/|') &&
+		rm .git/objects/$path
+	)
+}
+
+test_expect_success 'fsck notices missing blob' '
+	create_repo_missing HEAD:subdir/file &&
+	test_must_fail git -C missing fsck
+'
+
+test_expect_success 'fsck notices missing subtree' '
+	create_repo_missing HEAD:subdir &&
+	test_must_fail git -C missing fsck
+'
+
+test_expect_success 'fsck notices missing root tree' '
+	create_repo_missing HEAD^{tree} &&
+	test_must_fail git -C missing fsck
+'
+
+test_expect_success 'fsck notices missing parent' '
+	create_repo_missing HEAD^ &&
+	test_must_fail git -C missing fsck
+'
+
+test_expect_success 'fsck notices missing tagged object' '
+	create_repo_missing tag^{blob} &&
+	test_must_fail git -C missing fsck
+'
+
+test_expect_success 'fsck notices ref pointing to missing commit' '
+	create_repo_missing HEAD &&
+	test_must_fail git -C missing fsck
+'
+
+test_expect_success 'fsck notices ref pointing to missing tag' '
+	create_repo_missing tag &&
+	test_must_fail git -C missing fsck
+'
+
 test_done
diff --git a/t/t4212-log-corrupt.sh b/t/t4212-log-corrupt.sh
index 58b792bf20..67bd8ec020 100755
--- a/t/t4212-log-corrupt.sh
+++ b/t/t4212-log-corrupt.sh
@@ -14,7 +14,7 @@ test_expect_success 'setup' '
 '
 
 test_expect_success 'fsck notices broken commit' '
-	git fsck 2>actual &&
+	test_must_fail git fsck 2>actual &&
 	test_i18ngrep invalid.author actual
 '