diff --git a/builtin/am.c b/builtin/am.c
index 4ba44e2d70..faccc45b13 100644
--- a/builtin/am.c
+++ b/builtin/am.c
@@ -1718,6 +1718,7 @@ static void do_commit(const struct am_state *state)
 
 	run_hooks("post-applypatch");
 
+	free_commit_list(parents);
 	strbuf_release(&sb);
 }
 
diff --git a/builtin/commit-tree.c b/builtin/commit-tree.c
index 1bb7819839..84bb450222 100644
--- a/builtin/commit-tree.c
+++ b/builtin/commit-tree.c
@@ -111,6 +111,7 @@ int cmd_commit_tree(int argc, const char **argv, const char *prefix)
 			N_("GPG sign commit"), PARSE_OPT_OPTARG, NULL, (intptr_t) "" },
 		OPT_END()
 	};
+	int ret;
 
 	git_config(git_default_config, NULL);
 
@@ -132,11 +133,15 @@ int cmd_commit_tree(int argc, const char **argv, const char *prefix)
 
 	if (commit_tree(buffer.buf, buffer.len, &tree_oid, parents, &commit_oid,
 			NULL, sign_commit)) {
-		strbuf_release(&buffer);
-		return 1;
+		ret = 1;
+		goto out;
 	}
 
 	printf("%s\n", oid_to_hex(&commit_oid));
+	ret = 0;
+
+out:
+	free_commit_list(parents);
 	strbuf_release(&buffer);
-	return 0;
+	return ret;
 }
diff --git a/builtin/commit.c b/builtin/commit.c
index dcaf4efa03..d5713455e5 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -1848,7 +1848,6 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 		rollback_index_files();
 		die(_("failed to write commit object"));
 	}
-	free_commit_extra_headers(extra);
 
 	if (update_head_with_reflog(current_head, &oid, reflog_msg, &sb,
 				    &err)) {
@@ -1890,6 +1889,8 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 	apply_autostash_ref(the_repository, "MERGE_AUTOSTASH");
 
 cleanup:
+	free_commit_extra_headers(extra);
+	free_commit_list(parents);
 	strbuf_release(&author_ident);
 	strbuf_release(&err);
 	strbuf_release(&sb);
diff --git a/builtin/merge.c b/builtin/merge.c
index daed2d4e1e..50b0c87a95 100644
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -895,7 +895,7 @@ static void prepare_to_commit(struct commit_list *remoteheads)
 static int merge_trivial(struct commit *head, struct commit_list *remoteheads)
 {
 	struct object_id result_tree, result_commit;
-	struct commit_list *parents, **pptr = &parents;
+	struct commit_list *parents = NULL, **pptr = &parents;
 
 	if (repo_refresh_and_write_index(the_repository, REFRESH_QUIET,
 					 SKIP_IF_UNCHANGED, 0, NULL, NULL,
@@ -911,7 +911,9 @@ static int merge_trivial(struct commit *head, struct commit_list *remoteheads)
 			&result_commit, NULL, sign_commit))
 		die(_("failed to write commit object"));
 	finish(head, remoteheads, &result_commit, "In-index merge");
+
 	remove_merge_branch_state(the_repository);
+	free_commit_list(parents);
 	return 0;
 }
 
@@ -937,8 +939,10 @@ static int finish_automerge(struct commit *head,
 		die(_("failed to write commit object"));
 	strbuf_addf(&buf, "Merge made by the '%s' strategy.", wt_strategy);
 	finish(head, remoteheads, &result_commit, buf.buf);
+
 	strbuf_release(&buf);
 	remove_merge_branch_state(the_repository);
+	free_commit_list(parents);
 	return 0;
 }
 
diff --git a/builtin/replay.c b/builtin/replay.c
index 6bf0691f15..0448326636 100644
--- a/builtin/replay.c
+++ b/builtin/replay.c
@@ -52,11 +52,11 @@ static struct commit *create_commit(struct tree *tree,
 				    struct commit *parent)
 {
 	struct object_id ret;
-	struct object *obj;
+	struct object *obj = NULL;
 	struct commit_list *parents = NULL;
 	char *author;
 	char *sign_commit = NULL; /* FIXME: cli users might want to sign again */
-	struct commit_extra_header *extra;
+	struct commit_extra_header *extra = NULL;
 	struct strbuf msg = STRBUF_INIT;
 	const char *out_enc = get_commit_output_encoding();
 	const char *message = repo_logmsg_reencode(the_repository, based_on,
@@ -73,12 +73,16 @@ static struct commit *create_commit(struct tree *tree,
 	if (commit_tree_extended(msg.buf, msg.len, &tree->object.oid, parents,
 				 &ret, author, NULL, sign_commit, extra)) {
 		error(_("failed to write commit object"));
-		return NULL;
+		goto out;
 	}
-	free(author);
-	strbuf_release(&msg);
 
 	obj = parse_object(the_repository, &ret);
+
+out:
+	free_commit_extra_headers(extra);
+	free_commit_list(parents);
+	strbuf_release(&msg);
+	free(author);
 	return (struct commit *)obj;
 }
 
diff --git a/builtin/stash.c b/builtin/stash.c
index 1ed0a9a5d9..46b981c4dd 100644
--- a/builtin/stash.c
+++ b/builtin/stash.c
@@ -1416,6 +1416,9 @@ static int do_create_stash(const struct pathspec *ps, struct strbuf *stash_msg_b
 		goto done;
 	}
 
+	free_commit_list(parents);
+	parents = NULL;
+
 	if (include_untracked) {
 		if (save_untracked_files(info, &msg, untracked_files)) {
 			if (!quiet)
@@ -1461,11 +1464,6 @@ static int do_create_stash(const struct pathspec *ps, struct strbuf *stash_msg_b
 	else
 		strbuf_insertf(stash_msg_buf, 0, "On %s: ", branch_name);
 
-	/*
-	 * `parents` will be empty after calling `commit_tree()`, so there is
-	 * no need to call `free_commit_list()`
-	 */
-	parents = NULL;
 	if (untracked_commit_option)
 		commit_list_insert(lookup_commit(the_repository,
 						 &info->u_commit),
@@ -1487,6 +1485,7 @@ done:
 	strbuf_release(&commit_tree_label);
 	strbuf_release(&msg);
 	strbuf_release(&untracked_files);
+	free_commit_list(parents);
 	return ret;
 }
 
diff --git a/commit.c b/commit.c
index 1d08951007..f674eca320 100644
--- a/commit.c
+++ b/commit.c
@@ -1262,7 +1262,7 @@ int remove_signature(struct strbuf *buf)
 	return sigs[0].start != NULL;
 }
 
-static void handle_signed_tag(struct commit *parent, struct commit_extra_header ***tail)
+static void handle_signed_tag(const struct commit *parent, struct commit_extra_header ***tail)
 {
 	struct merge_remote_desc *desc;
 	struct commit_extra_header *mergetag;
@@ -1359,17 +1359,17 @@ void verify_merge_signature(struct commit *commit, int verbosity,
 	signature_check_clear(&signature_check);
 }
 
-void append_merge_tag_headers(struct commit_list *parents,
+void append_merge_tag_headers(const struct commit_list *parents,
 			      struct commit_extra_header ***tail)
 {
 	while (parents) {
-		struct commit *parent = parents->item;
+		const struct commit *parent = parents->item;
 		handle_signed_tag(parent, tail);
 		parents = parents->next;
 	}
 }
 
-static int convert_commit_extra_headers(struct commit_extra_header *orig,
+static int convert_commit_extra_headers(const struct commit_extra_header *orig,
 					struct commit_extra_header **result)
 {
 	const struct git_hash_algo *compat = the_repository->compat_hash_algo;
@@ -1403,7 +1403,7 @@ static int convert_commit_extra_headers(struct commit_extra_header *orig,
 }
 
 static void add_extra_header(struct strbuf *buffer,
-			     struct commit_extra_header *extra)
+			     const struct commit_extra_header *extra)
 {
 	strbuf_addstr(buffer, extra->key);
 	if (extra->len)
@@ -1517,7 +1517,7 @@ void free_commit_extra_headers(struct commit_extra_header *extra)
 }
 
 int commit_tree(const char *msg, size_t msg_len, const struct object_id *tree,
-		struct commit_list *parents, struct object_id *ret,
+		const struct commit_list *parents, struct object_id *ret,
 		const char *author, const char *sign_commit)
 {
 	struct commit_extra_header *extra = NULL, **tail = &extra;
@@ -1649,7 +1649,7 @@ static void write_commit_tree(struct strbuf *buffer, const char *msg, size_t msg
 			      const struct object_id *tree,
 			      const struct object_id *parents, size_t parents_len,
 			      const char *author, const char *committer,
-			      struct commit_extra_header *extra)
+			      const struct commit_extra_header *extra)
 {
 	int encoding_is_utf8;
 	size_t i;
@@ -1690,10 +1690,10 @@ static void write_commit_tree(struct strbuf *buffer, const char *msg, size_t msg
 
 int commit_tree_extended(const char *msg, size_t msg_len,
 			 const struct object_id *tree,
-			 struct commit_list *parents, struct object_id *ret,
+			 const struct commit_list *parents, struct object_id *ret,
 			 const char *author, const char *committer,
 			 const char *sign_commit,
-			 struct commit_extra_header *extra)
+			 const struct commit_extra_header *extra)
 {
 	struct repository *r = the_repository;
 	int result = 0;
@@ -1715,10 +1715,8 @@ int commit_tree_extended(const char *msg, size_t msg_len,
 	nparents = commit_list_count(parents);
 	CALLOC_ARRAY(parent_buf, nparents);
 	i = 0;
-	while (parents) {
-		struct commit *parent = pop_commit(&parents);
-		oidcpy(&parent_buf[i++], &parent->object.oid);
-	}
+	for (const struct commit_list *p = parents; p; p = p->next)
+		oidcpy(&parent_buf[i++], &p->item->object.oid);
 
 	write_commit_tree(&buffer, msg, msg_len, tree, parent_buf, nparents, author, committer, extra);
 	if (sign_commit && sign_commit_to_strbuf(&sig, &buffer, sign_commit)) {
@@ -1814,7 +1812,7 @@ out:
 define_commit_slab(merge_desc_slab, struct merge_remote_desc *);
 static struct merge_desc_slab merge_desc_slab = COMMIT_SLAB_INIT(1, merge_desc_slab);
 
-struct merge_remote_desc *merge_remote_util(struct commit *commit)
+struct merge_remote_desc *merge_remote_util(const struct commit *commit)
 {
 	return *merge_desc_slab_at(&merge_desc_slab, commit);
 }
diff --git a/commit.h b/commit.h
index 62fe0d77a7..442e50ff24 100644
--- a/commit.h
+++ b/commit.h
@@ -260,19 +260,19 @@ struct commit_extra_header {
 	size_t len;
 };
 
-void append_merge_tag_headers(struct commit_list *parents,
+void append_merge_tag_headers(const struct commit_list *parents,
 			      struct commit_extra_header ***tail);
 
 int commit_tree(const char *msg, size_t msg_len,
 		const struct object_id *tree,
-		struct commit_list *parents, struct object_id *ret,
+		const struct commit_list *parents, struct object_id *ret,
 		const char *author, const char *sign_commit);
 
 int commit_tree_extended(const char *msg, size_t msg_len,
 			 const struct object_id *tree,
-			 struct commit_list *parents, struct object_id *ret,
+			 const struct commit_list *parents, struct object_id *ret,
 			 const char *author, const char *committer,
-			 const char *sign_commit, struct commit_extra_header *);
+			 const char *sign_commit, const struct commit_extra_header *);
 
 struct commit_extra_header *read_commit_extra_headers(struct commit *, const char **);
 
@@ -306,7 +306,7 @@ struct merge_remote_desc {
 	struct object *obj; /* the named object, could be a tag */
 	char name[FLEX_ARRAY];
 };
-struct merge_remote_desc *merge_remote_util(struct commit *);
+struct merge_remote_desc *merge_remote_util(const struct commit *);
 void set_merge_remote_desc(struct commit *commit,
 			   const char *name, struct object *obj);
 
diff --git a/notes-merge.c b/notes-merge.c
index 6a9a139b12..f3cc84f45d 100644
--- a/notes-merge.c
+++ b/notes-merge.c
@@ -661,6 +661,7 @@ int notes_merge(struct notes_merge_options *o,
 		commit_list_insert(local, &parents);
 		create_notes_commit(o->repo, local_tree, parents, o->commit_msg.buf,
 				    o->commit_msg.len, result_oid);
+		free_commit_list(parents);
 	}
 
 found_result:
diff --git a/notes-utils.c b/notes-utils.c
index 671d1969b1..3198c14e4d 100644
--- a/notes-utils.c
+++ b/notes-utils.c
@@ -9,10 +9,11 @@
 
 void create_notes_commit(struct repository *r,
 			 struct notes_tree *t,
-			 struct commit_list *parents,
+			 const struct commit_list *parents,
 			 const char *msg, size_t msg_len,
 			 struct object_id *result_oid)
 {
+	struct commit_list *parents_to_free = NULL;
 	struct object_id tree_oid;
 
 	assert(t->initialized);
@@ -27,7 +28,8 @@ void create_notes_commit(struct repository *r,
 			struct commit *parent = lookup_commit(r, &parent_oid);
 			if (repo_parse_commit(r, parent))
 				die("Failed to find/parse commit %s", t->ref);
-			commit_list_insert(parent, &parents);
+			commit_list_insert(parent, &parents_to_free);
+			parents = parents_to_free;
 		}
 		/* else: t->ref points to nothing, assume root/orphan commit */
 	}
@@ -35,6 +37,8 @@ void create_notes_commit(struct repository *r,
 	if (commit_tree(msg, msg_len, &tree_oid, parents, result_oid, NULL,
 			NULL))
 		die("Failed to commit notes tree to database");
+
+	free_commit_list(parents_to_free);
 }
 
 void commit_notes(struct repository *r, struct notes_tree *t, const char *msg)
diff --git a/notes-utils.h b/notes-utils.h
index d9b3c09eaf..c54b1fe141 100644
--- a/notes-utils.h
+++ b/notes-utils.h
@@ -20,7 +20,7 @@ struct repository;
  */
 void create_notes_commit(struct repository *r,
 			 struct notes_tree *t,
-			 struct commit_list *parents,
+			 const struct commit_list *parents,
 			 const char *msg, size_t msg_len,
 			 struct object_id *result_oid);
 
diff --git a/sequencer.c b/sequencer.c
index 30513e87bf..475646671a 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -1711,6 +1711,7 @@ static int try_to_commit(struct repository *r,
 
 out:
 	free_commit_extra_headers(extra);
+	free_commit_list(parents);
 	strbuf_release(&err);
 	strbuf_release(&commit_msg);
 	free(amend_author);
diff --git a/t/t3403-rebase-skip.sh b/t/t3403-rebase-skip.sh
index a1911c4a9d..4f1d6e8ea6 100755
--- a/t/t3403-rebase-skip.sh
+++ b/t/t3403-rebase-skip.sh
@@ -8,6 +8,7 @@ test_description='git rebase --merge --skip tests'
 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 . "$TEST_DIRECTORY"/lib-rebase.sh
diff --git a/t/t3424-rebase-empty.sh b/t/t3424-rebase-empty.sh
index 1ee6b00fd5..515c949ae3 100755
--- a/t/t3424-rebase-empty.sh
+++ b/t/t3424-rebase-empty.sh
@@ -2,6 +2,7 @@
 
 test_description='git rebase of commits that start or become empty'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_expect_success 'setup test repository' '
diff --git a/t/t3505-cherry-pick-empty.sh b/t/t3505-cherry-pick-empty.sh
index 9748443530..ead3fb4680 100755
--- a/t/t3505-cherry-pick-empty.sh
+++ b/t/t3505-cherry-pick-empty.sh
@@ -5,6 +5,7 @@ test_description='test cherry-picking an empty commit'
 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_expect_success setup '
diff --git a/t/t7505-prepare-commit-msg-hook.sh b/t/t7505-prepare-commit-msg-hook.sh
index 2128142a61..b88383df9e 100755
--- a/t/t7505-prepare-commit-msg-hook.sh
+++ b/t/t7505-prepare-commit-msg-hook.sh
@@ -5,6 +5,7 @@ test_description='prepare-commit-msg hook'
 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_expect_success 'set up commits for rebasing' '