[PATCH] commit-graph: avoid memory leaks
- From
- Jonathan Tan <jonathantanmy@google.com>
- Date
- May 4, 2020, 19:13 UTC
- Message-ID
- <20200504191324.201663-1-jonathantanmy@google.com>
A fuzzer running on the entry point provided by fuzz-commit-graph.c revealed a memory leak when parse_commit_graph() creates a struct bloom_filter_settings and then returns early due to error. Fix that error by always freeing that struct first (if it exists) before returning early due to error.
While making that change, I also noticed another possible memory leak - when the BLOOMDATA chunk is provided but not BLOOMINDEXES. Also fix that error.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com> --- Here's a memory leak fix revealed by a fuzzer running at $DAYJOB, and another one that I noticed while making that fix. --- commit-graph.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-)
diff --git a/commit-graph.c b/commit-graph.c index 6dc777e2f3..1694f0a691 100644 --- a/commit-graph.c +++ b/commit-graph.c @@ -281,8 +281,7 @@ struct commit_graph *parse_commit_graph(void *graph_map, size_t graph_size) if (data + graph_size - chunk_lookup < GRAPH_CHUNKLOOKUP_WIDTH) { error(_("commit-graph chunk lookup table entry missing; file may be incomplete")); - free(graph); - return NULL; + goto free_and_return; } chunk_id = get_be32(chunk_lookup + 0); @@ -293,8 +292,7 @@ struct commit_graph *parse_commit_graph(void *graph_map, size_t graph_size) if (chunk_offset > graph_size - the_hash_algo->rawsz) { error(_("commit-graph improper chunk offset %08x%08x"), (uint32_t)(chunk_offset >> 32), (uint32_t)chunk_offset); - free(graph); - return NULL; + goto free_and_return; } switch (chunk_id) { @@ -361,8 +359,7 @@ struct commit_graph *parse_commit_graph(void *graph_map, size_t graph_size) if (chunk_repeated) { error(_("commit-graph chunk id %08x appears multiple times"), chunk_id); - free(graph); - return NULL; + goto free_and_return; } if (last_chunk_id == GRAPH_CHUNKID_OIDLOOKUP) @@ -381,17 +378,20 @@ struct commit_graph *parse_commit_graph(void *graph_map, size_t graph_size) /* We need both the bloom chunks to exist together. Else ignore the data */ graph->chunk_bloom_indexes = NULL; graph->chunk_bloom_data = NULL; - graph->bloom_filter_settings = NULL; + FREE_AND_NULL(graph->bloom_filter_settings); } hashcpy(graph->oid.hash, graph->data + graph->data_len - graph->hash_len); - if (verify_commit_graph_lite(graph)) { - free(graph); - return NULL; - } + if (verify_commit_graph_lite(graph)) + goto free_and_return; return graph; + +free_and_return: + free(graph->bloom_filter_settings); + free(graph); + return NULL; } static struct commit_graph *load_commit_graph_one(const char *graph_file,
-- 2.26.2.526.g744177e7f7-goog