Am 26.08.19 um 19:20 schrieb Junio C Hamano:
> Stefan Sperling <stsp@xxxxxxxxx> writes:
>
>> The root cause of this bug seems to be that the valid assumption
>> that obj->parsed implies a successfully parsed object is broken by
>> parse_tag_buffer() because this function sets the 'parsed' flag even
>> if errors occur during parsing.
>
> I am mildly negative about that approach. obj->parsed is about
> "we've done all we need to do to attempt parsing this object" (so
> that next person who gets hold of the object knows that fact---one
> of the reasons why may be that the caller who wants to ensure that
> the fields are ready to be accessed does not have to spend extra
> cycles, but that is not the only one). Those that want to look at
> various fields in the object (e.g. the tagged object of a tag, the
> tagger identity of a tag, etc.) should be prepared to see and react
> to NULL in there so that they can gracefully handle "slightly"
> corrupt objects.
Not sure how this could happen under normal circumstances, but how
about this here?
-- >8 --
Subject: [PATCH] tree: simplify parse_tree_indirect()
Reduce code duplication by turning parse_tree_indirect() into a wrapper
of repo_peel_to_type(). This avoids a segfault when handling a broken
tag where ->tagged is NULL. The new version also checks the return
value of parse_object() that was ignored by the old one.
Initial-patch-by: Stefan Sperling <stsp@xxxxxxxxx>
Signed-off-by: René Scharfe <l.s.r@xxxxxx>
---
tree.c | 18 +++---------------
1 file changed, 3 insertions(+), 15 deletions(-)
diff --git a/tree.c b/tree.c
index 4720945e6a..1466bcc6a8 100644
--- a/tree.c
+++ b/tree.c
@@ -244,19 +244,7 @@ void free_tree_buffer(struct tree *tree)
struct tree *parse_tree_indirect(const struct object_id *oid)
{
- struct object *obj = parse_object(the_repository, oid);
- do {
- if (!obj)
- return NULL;
- if (obj->type == OBJ_TREE)
- return (struct tree *) obj;
- else if (obj->type == OBJ_COMMIT)
- obj = &(get_commit_tree(((struct commit *)obj))->object);
- else if (obj->type == OBJ_TAG)
- obj = ((struct tag *) obj)->tagged;
- else
- return NULL;
- if (!obj->parsed)
- parse_object(the_repository, &obj->oid);
- } while (1);
+ struct repository *r = the_repository;
+ struct object *obj = parse_object(r, oid);
+ return (struct tree *)repo_peel_to_type(r, NULL, 0, obj, OBJ_TREE);
}
--
2.23.0
