[PATCH 09/14] commit-graph: fix memory leak in misused string_list API
- From
Ævar Arnfjörð Bjarmason <avarab@gmail.com>
- Date
- Mar 2, 2022, 17:10 UTC
- Message-ID
- <patch-09.14-b5512deb26f-20220302T170718Z-avarab@gmail.com>
- In-Reply-To
- <cover-00.14-00000000000-20220302T170718Z-avarab@gmail.com>
When this code was migrated to the string_list API in d88b14b3fd6 (commit-graph: use string-list API for input, 2018-06-27) it was made to use used both STRING_LIST_INIT_NODUP and a strbuf_detach() pattern.
Those should not be used together if string_list_clear() is expected to free the memory, instead we need to either use STRING_LIST_INIT_DUP with a string_list_append_nodup(), or a STRING_LIST_INIT_NODUP and manually fiddle with the "strdup_strings" member before calling string_list_clear(). Let's do the former.
Since "strdup_strings = 1" is set now other code might be broken by relying on "pack_indexes" not to duplicate it strings, but that doesn't happen. When we pass this down to write_commit_graph() that code uses the "struct string_list" without modifying it. Let's add a "const" to the variable to have the compiler enforce that assumption.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> --- builtin/commit-graph.c | 6 +++--- commit-graph.c | 4 ++-- commit-graph.h | 2 +- 3 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c index 4247fbde95a..51c4040ea6c 100644 --- a/builtin/commit-graph.c +++ b/builtin/commit-graph.c @@ -192,7 +192,7 @@ static int git_commit_graph_write_config(const char *var, const char *value, static int graph_write(int argc, const char **argv) { - struct string_list pack_indexes = STRING_LIST_INIT_NODUP; + struct string_list pack_indexes = STRING_LIST_INIT_DUP; struct strbuf buf = STRBUF_INIT; struct oidset commits = OIDSET_INIT; struct object_directory *odb = NULL; @@ -273,8 +273,8 @@ static int graph_write(int argc, const char **argv) if (opts.stdin_packs) { while (strbuf_getline(&buf, stdin) != EOF) - string_list_append(&pack_indexes, - strbuf_detach(&buf, NULL)); + string_list_append_nodup(&pack_indexes, + strbuf_detach(&buf, NULL)); } else if (opts.stdin_commits) { oidset_init(&commits, 0); if (opts.progress) diff --git a/commit-graph.c b/commit-graph.c index 265c010122e..d0c94600bab 100644 --- a/commit-graph.c +++ b/commit-graph.c @@ -1679,7 +1679,7 @@ int write_commit_graph_reachable(struct object_directory *odb, } static int fill_oids_from_packs(struct write_commit_graph_context *ctx, - struct string_list *pack_indexes) + const struct string_list *pack_indexes) { uint32_t i; struct strbuf progress_title = STRBUF_INIT; @@ -2259,7 +2259,7 @@ static void expire_commit_graphs(struct write_commit_graph_context *ctx) } int write_commit_graph(struct object_directory *odb, - struct string_list *pack_indexes, + const struct string_list *const pack_indexes, struct oidset *commits, enum commit_graph_write_flags flags, const struct commit_graph_opts *opts) diff --git a/commit-graph.h b/commit-graph.h index 04a94e18302..2e3ac35237e 100644 --- a/commit-graph.h +++ b/commit-graph.h @@ -142,7 +142,7 @@ int write_commit_graph_reachable(struct object_directory *odb, enum commit_graph_write_flags flags, const struct commit_graph_opts *opts); int write_commit_graph(struct object_directory *odb, - struct string_list *pack_indexes, + const struct string_list *pack_indexes, struct oidset *commits, enum commit_graph_write_flags flags, const struct commit_graph_opts *opts);
-- 2.35.1.1228.g56895c6ee86