commit-graph: verify parent list
The commit-graph file stores parents in a two-column portion of the commit data chunk. If there is only one parent, then the second column stores 0xFFFFFFFF to indicate no second parent. The 'verify' subcommand checks the parent list for the commit loaded from the commit-graph and the one parsed from the object database. Test these checks for corrupt parents, too many parents, and wrong parents. Add a boundary check to insert_parent_or_die() for when the parent position value is out of range. The octopus merge will be tested in a later commit. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Derrick Stolee committed
Jun 27, 2018 at 09:24 UTC
53614b13516ffd27bb045b696d0815b9da435cb0
2 files changed
+46
commit-graph.c
+28
@@ -244,6 +244,9 @@ static struct commit_list **insert_parent_or_die(struct commit_graph *g,
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struct commit *c;
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struct object_id oid;
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+ if (pos >= g->num_commits)
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+ die("invalid parent position %"PRIu64, pos);
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+
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hashcpy(oid.hash, g->chunk_oid_lookup + g->hash_len * pos);
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c = lookup_commit(&oid);
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if (!c)
@@ -907,6 +910,7 @@ int verify_commit_graph(struct repository *r, struct commit_graph *g)
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for (i = 0; i < g->num_commits; i++) {
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struct commit *graph_commit, *odb_commit;
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+ struct commit_list *graph_parents, *odb_parents;
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hashcpy(cur_oid.hash, g->chunk_oid_lookup + g->hash_len * i);
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@@ -924,6 +928,30 @@ int verify_commit_graph(struct repository *r, struct commit_graph *g)
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oid_to_hex(&cur_oid),
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oid_to_hex(get_commit_tree_oid(graph_commit)),
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oid_to_hex(get_commit_tree_oid(odb_commit)));
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+
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+ graph_parents = graph_commit->parents;
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+ odb_parents = odb_commit->parents;
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+
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+ while (graph_parents) {
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+ if (odb_parents == NULL) {
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+ graph_report("commit-graph parent list for commit %s is too long",
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+ oid_to_hex(&cur_oid));
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+ break;
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+ }
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+
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+ if (oidcmp(&graph_parents->item->object.oid, &odb_parents->item->object.oid))
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+ graph_report("commit-graph parent for %s is %s != %s",
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+ oid_to_hex(&cur_oid),
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+ oid_to_hex(&graph_parents->item->object.oid),
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+ oid_to_hex(&odb_parents->item->object.oid));
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+
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+ graph_parents = graph_parents->next;
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+ odb_parents = odb_parents->next;
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+ }
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+
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+ if (odb_parents != NULL)
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+ graph_report("commit-graph parent list for commit %s terminates early",
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+ oid_to_hex(&cur_oid));
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}
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return verify_commit_graph_error;
t/t5318-commit-graph.sh
+18
@@ -269,6 +269,9 @@ GRAPH_BYTE_OID_LOOKUP_ORDER=$(($GRAPH_OID_LOOKUP_OFFSET + $HASH_LEN * 8))
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GRAPH_BYTE_OID_LOOKUP_MISSING=$(($GRAPH_OID_LOOKUP_OFFSET + $HASH_LEN * 4 + 10))
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GRAPH_COMMIT_DATA_OFFSET=$(($GRAPH_OID_LOOKUP_OFFSET + $HASH_LEN * $NUM_COMMITS))
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GRAPH_BYTE_COMMIT_TREE=$GRAPH_COMMIT_DATA_OFFSET
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+GRAPH_BYTE_COMMIT_PARENT=$(($GRAPH_COMMIT_DATA_OFFSET + $HASH_LEN))
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+GRAPH_BYTE_COMMIT_EXTRA_PARENT=$(($GRAPH_COMMIT_DATA_OFFSET + $HASH_LEN + 4))
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+GRAPH_BYTE_COMMIT_WRONG_PARENT=$(($GRAPH_COMMIT_DATA_OFFSET + $HASH_LEN + 3))
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# usage: corrupt_graph_and_verify <position> <data> <string>
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# Manipulates the commit-graph file at the position
@@ -348,4 +351,19 @@ test_expect_success 'detect incorrect tree OID' '
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"root tree OID for commit"
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'
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+test_expect_success 'detect incorrect parent int-id' '
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+ corrupt_graph_and_verify $GRAPH_BYTE_COMMIT_PARENT "\01" \
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+ "invalid parent"
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+'
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+
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+test_expect_success 'detect extra parent int-id' '
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+ corrupt_graph_and_verify $GRAPH_BYTE_COMMIT_EXTRA_PARENT "\00" \
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+ "is too long"
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+'
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+
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+test_expect_success 'detect wrong parent' '
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+ corrupt_graph_and_verify $GRAPH_BYTE_COMMIT_WRONG_PARENT "\01" \
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+ "commit-graph parent for"
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+'
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+
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test_done