[PATCH 7/9] commit-graph: check order while reading fanout chunk
- From
Jeff King <peff@peff.net>
- Date
- Nov 9, 2023, 07:25 UTC
- Message-ID
- <20231109072507.GG2698043@coredump.intra.peff.net>
- In-Reply-To
- <20231109070310.GA2697602@coredump.intra.peff.net>
We read the fanout chunk, storing a pointer to it, but only confirm that the entries are monotonic in a final "lite" verification step. Let's move that into the actual OIDF chunk callback, so that we can report problems immediately (for all the reasons given in the previous "commit-graph: abort as soon as we see a bogus chunk" commit).
Signed-off-by: Jeff King <peff@peff.net> --- commit-graph.c | 25 +++++++++++++------------ t/t5318-commit-graph.sh | 1 + 2 files changed, 14 insertions(+), 12 deletions(-)
diff --git a/commit-graph.c b/commit-graph.c index 094814c2ba..4ba523cd15 100644 --- a/commit-graph.c +++ b/commit-graph.c @@ -277,8 +277,6 @@ struct commit_graph *load_commit_graph_one_fd_st(struct repository *r, static int verify_commit_graph_lite(struct commit_graph *g) { - int i; - /* * Basic validation shared between parse_commit_graph() * which'll be called every time the graph is used, and the @@ -291,27 +289,30 @@ static int verify_commit_graph_lite(struct commit_graph *g) * over g->num_commits, or runs a checksum on the commit-graph * itself. */ - for (i = 0; i < 255; i++) { - uint32_t oid_fanout1 = ntohl(g->chunk_oid_fanout[i]); - uint32_t oid_fanout2 = ntohl(g->chunk_oid_fanout[i + 1]); - - if (oid_fanout1 > oid_fanout2) { - error("commit-graph fanout values out of order"); - return 1; - } - } - return 0; } static int graph_read_oid_fanout(const unsigned char *chunk_start, size_t chunk_size, void *data) { struct commit_graph *g = data; + int i; + if (chunk_size != 256 * sizeof(uint32_t)) return error("commit-graph oid fanout chunk is wrong size"); g->chunk_oid_fanout = (const uint32_t *)chunk_start; g->num_commits = ntohl(g->chunk_oid_fanout[255]); + + for (i = 0; i < 255; i++) { + uint32_t oid_fanout1 = ntohl(g->chunk_oid_fanout[i]); + uint32_t oid_fanout2 = ntohl(g->chunk_oid_fanout[i + 1]); + + if (oid_fanout1 > oid_fanout2) { + error("commit-graph fanout values out of order"); + return 1; + } + } + return 0; } diff --git a/t/t5318-commit-graph.sh b/t/t5318-commit-graph.sh index 8bd7fcefb5..7fe7c72a87 100755 --- a/t/t5318-commit-graph.sh +++ b/t/t5318-commit-graph.sh @@ -867,6 +867,7 @@ test_expect_success 'reader notices out-of-bounds fanout' ' check_corrupt_chunk OIDF 0 $(printf "%02x000000" $(test_seq 0 254)) && cat >expect.err <<-\EOF && error: commit-graph fanout values out of order + error: commit-graph required OID fanout chunk missing or corrupted EOF test_cmp expect.err err '
-- 2.43.0.rc1.572.g273fc7bed6