[PATCH 3/4] builtin-fast-export.c: fix crash on tagged trees

[Erik Faye-Lund <kusmabite@gmail.com>]

If a tag object points to a tree (or another unhandled type), the commit-
pointer is left uninitialized and later dereferenced. This patch adds a default
case to the switch that issues a warning and skips the object.

Signed-off-by: Erik Faye-Lund <kusmabite@gmail.com>
---
 builtin-fast-export.c  |    4 ++++
 t/t9301-fast-export.sh |    4 ++--
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/builtin-fast-export.c b/builtin-fast-export.c
index 027c4aa..2070288 100644
--- a/builtin-fast-export.c
+++ b/builtin-fast-export.c
@@ -376,6 +376,10 @@ static void get_tags_and_duplicates(struct object_array *pending,
 			case OBJ_BLOB:
 				handle_object(tag->object.sha1);
 				continue;
+			default:
+				warning("Tag points to object of unexpected type %s, skipping.",
+				        typename(tag->object.type));
+				continue;
 			}
 			break;
 		default:
diff --git a/t/t9301-fast-export.sh b/t/t9301-fast-export.sh
index 763dde5..b587feb 100755
--- a/t/t9301-fast-export.sh
+++ b/t/t9301-fast-export.sh
@@ -274,8 +274,8 @@ test_expect_success 'set-up a few more tags for tag export tests' '
 '
 
 # NEEDSWORK: not just check return status, but validate the output
-test_expect_failure 'tree_tag'        'git fast-export tree_tag'
-test_expect_failure 'tree_tag-obj'    'git fast-export tree_tag-obj'
+test_expect_success 'tree_tag'        'git fast-export tree_tag'
+test_expect_success 'tree_tag-obj'    'git fast-export tree_tag-obj'
 test_expect_failure 'tag-obj_tag'     'git fast-export tag-obj_tag'
 test_expect_failure 'tag-obj_tag-obj' 'git fast-export tag-obj_tag-obj'
 
-- 
1.6.2.1