[PATCH 05/12] load_subtree(): separate logic for internal vs. terminal entries
- From
Michael Haggerty <mhagger@alum.mit.edu>
- Date
- Aug 26, 2017, 08:28 UTC
- Message-ID
- <b76c9b2596b4385ee40ea4da7f56190cf6d225f2.1503734566.git.mhagger@alum.mit.edu>
- In-Reply-To
- <cover.1503734566.git.mhagger@alum.mit.edu>
There are only two legitimate notes path components:
* A hexadecimal string that fills the rest of the SHA-1
* A two-digit hexadecimal string that constitutes another internal node.
So handle those two cases at the top level, and reject others as non-notes without trying to parse them. The logic separation also simplifies upcoming changes.
This prevents us from leaking memory for a leaf_node in the case of wrong-sized paths. There are still memory leaks in this code; they will be fixed in upcoming commits.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> --- notes.c | 52 +++++++++++++++++++++++++++++++--------------------- 1 file changed, 31 insertions(+), 21 deletions(-)
diff --git a/notes.c b/notes.c index 62ab3f4ce3..768902055e 100644 --- a/notes.c +++ b/notes.c @@ -433,30 +433,40 @@ static void load_subtree(struct notes_tree *t, struct leaf_node *subtree, while (tree_entry(&desc, &entry)) { unsigned char type; struct leaf_node *l; - int len, path_len = strlen(entry.path); + int path_len = strlen(entry.path); + + if (path_len == 2 * (GIT_SHA1_RAWSZ - prefix_len)) { + /* This is potentially the remainder of the SHA-1 */ + if (get_oid_hex_segment(entry.path, path_len, + object_oid.hash + prefix_len, + GIT_SHA1_RAWSZ - prefix_len) < 0) + goto handle_non_note; /* entry.path is not a SHA1 */ + + type = PTR_TYPE_NOTE; + l = (struct leaf_node *) + xcalloc(1, sizeof(struct leaf_node)); + oidcpy(&l->key_oid, &object_oid); + oidcpy(&l->val_oid, entry.oid); + } else if (path_len == 2) { + /* This is potentially an internal node */ + if (get_oid_hex_segment(entry.path, 2, + object_oid.hash + prefix_len, + GIT_SHA1_RAWSZ - prefix_len) < 0) + goto handle_non_note; /* entry.path is not a SHA1 */ - len = get_oid_hex_segment(entry.path, path_len, - object_oid.hash + prefix_len, GIT_SHA1_RAWSZ - prefix_len); - if (len < 0) - goto handle_non_note; /* entry.path is not a SHA1 */ - len += prefix_len; - - /* - * If object SHA1 is complete (len == 20), assume note object - * If object SHA1 is incomplete (len < 20), and current - * component consists of 2 hex chars, assume note subtree - */ - type = PTR_TYPE_NOTE; - l = (struct leaf_node *) - xcalloc(1, sizeof(struct leaf_node)); - oidcpy(&l->key_oid, &object_oid); - oidcpy(&l->val_oid, entry.oid); - if (len < GIT_SHA1_RAWSZ) { - if (!S_ISDIR(entry.mode) || path_len != 2) - goto handle_non_note; /* not subtree */ - l->key_oid.hash[KEY_INDEX] = (unsigned char) len; type = PTR_TYPE_SUBTREE; + l = (struct leaf_node *) + xcalloc(1, sizeof(struct leaf_node)); + oidcpy(&l->key_oid, &object_oid); + oidcpy(&l->val_oid, entry.oid); + if (!S_ISDIR(entry.mode)) + goto handle_non_note; /* not subtree */ + l->key_oid.hash[KEY_INDEX] = (unsigned char) (prefix_len + 1); + } else { + /* This can't be part of a note */ + goto handle_non_note; } + if (note_tree_insert(t, node, n, l, type, combine_notes_concatenate)) die("Failed to load %s %s into notes tree "
-- 2.11.0