[PATCH] receive-pack: check object type of sha1 before using them as commits
From: Martin Koegler <hidden>
Date: 2016-06-15 22:44:02
Signed-off-by: Martin Koegler <redacted> --- receive-pack.c | 14 ++++++++++++-- 1 files changed, 12 insertions(+), 2 deletions(-)
diff --git a/receive-pack.c b/receive-pack.c
index fba4cf8..d0a563d 100644
--- a/receive-pack.c
+++ b/receive-pack.c@@ -178,11 +178,21 @@ static const char *update(struct command *cmd) if (deny_non_fast_forwards && !is_null_sha1(new_sha1) && !is_null_sha1(old_sha1) && !prefixcmp(name, "refs/heads/")) { + struct object *old_object, *new_object; struct commit *old_commit, *new_commit; struct commit_list *bases, *ent; - old_commit = (struct commit *)parse_object(old_sha1); - new_commit = (struct commit *)parse_object(new_sha1); + old_object = parse_object(old_sha1); + new_object = parse_object(new_sha1); + + if (!old_object || !new_object || + old_object->type != OBJ_COMMIT || + new_object->type != OBJ_COMMIT) { + error("bad sha1 objects for %s", name); + return "bad ref"; + } + old_commit = (struct commit *)old_object; + new_commit = (struct commit *)new_object; bases = get_merge_bases(old_commit, new_commit, 1); for (ent = bases; ent; ent = ent->next) if (!hashcmp(old_sha1, ent->item->object.sha1))
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1.4.4.4