diff --git a/t/helper/test-bloom.c b/t/helper/test-bloom.c
index ad3ef1cd77..6c900ca668 100644
--- a/t/helper/test-bloom.c
+++ b/t/helper/test-bloom.c
@@ -16,6 +16,7 @@ static void add_string_to_filter(const char *data, struct bloom_filter *filter)
 		}
 		printf("\n");
 		add_key_to_filter(&key, filter, &settings);
+		clear_bloom_key(&key);
 }
 
 static void print_bloom_filter(struct bloom_filter *filter) {
@@ -80,6 +81,7 @@ int cmd__bloom(int argc, const char **argv)
 		}
 
 		print_bloom_filter(&filter);
+		free(filter.data);
 	}
 
 	if (!strcmp(argv[1], "get_filter_for_commit")) {
diff --git a/t/helper/test-delta.c b/t/helper/test-delta.c
index e749a49c88..b15481ea59 100644
--- a/t/helper/test-delta.c
+++ b/t/helper/test-delta.c
@@ -20,8 +20,9 @@ int cmd__delta(int argc, const char **argv)
 {
 	int fd;
 	struct stat st;
-	void *from_buf, *data_buf, *out_buf;
+	void *from_buf = NULL, *data_buf = NULL, *out_buf = NULL;
 	unsigned long from_size, data_size, out_size;
+	int ret = 1;
 
 	if (argc != 5 || (strcmp(argv[1], "-d") && strcmp(argv[1], "-p"))) {
 		fprintf(stderr, "usage: %s\n", usage_str);
@@ -38,21 +39,21 @@ int cmd__delta(int argc, const char **argv)
 	if (read_in_full(fd, from_buf, from_size) < 0) {
 		perror(argv[2]);
 		close(fd);
-		return 1;
+		goto cleanup;
 	}
 	close(fd);
 
 	fd = open(argv[3], O_RDONLY);
 	if (fd < 0 || fstat(fd, &st)) {
 		perror(argv[3]);
-		return 1;
+		goto cleanup;
 	}
 	data_size = st.st_size;
 	data_buf = xmalloc(data_size);
 	if (read_in_full(fd, data_buf, data_size) < 0) {
 		perror(argv[3]);
 		close(fd);
-		return 1;
+		goto cleanup;
 	}
 	close(fd);
 
@@ -66,14 +67,20 @@ int cmd__delta(int argc, const char **argv)
 				      &out_size);
 	if (!out_buf) {
 		fprintf(stderr, "delta operation failed (returned NULL)\n");
-		return 1;
+		goto cleanup;
 	}
 
 	fd = open (argv[4], O_WRONLY|O_CREAT|O_TRUNC, 0666);
 	if (fd < 0 || write_in_full(fd, out_buf, out_size) < 0) {
 		perror(argv[4]);
-		return 1;
+		goto cleanup;
 	}
 
-	return 0;
+	ret = 0;
+cleanup:
+	free(from_buf);
+	free(data_buf);
+	free(out_buf);
+
+	return ret;
 }
diff --git a/t/helper/test-dump-cache-tree.c b/t/helper/test-dump-cache-tree.c
index 6a3f88f5f5..0d6d7f1ecb 100644
--- a/t/helper/test-dump-cache-tree.c
+++ b/t/helper/test-dump-cache-tree.c
@@ -59,11 +59,16 @@ int cmd__dump_cache_tree(int ac, const char **av)
 {
 	struct index_state istate;
 	struct cache_tree *another = cache_tree();
+	int ret;
+
 	setup_git_directory();
 	if (read_cache() < 0)
 		die("unable to read index file");
 	istate = the_index;
 	istate.cache_tree = another;
 	cache_tree_update(&istate, WRITE_TREE_DRY_RUN);
-	return dump_cache_tree(active_cache_tree, another, "");
+	ret = dump_cache_tree(active_cache_tree, another, "");
+	cache_tree_free(&another);
+
+	return ret;
 }
diff --git a/t/helper/test-hash.c b/t/helper/test-hash.c
index 261c545b9d..5860dab0ff 100644
--- a/t/helper/test-hash.c
+++ b/t/helper/test-hash.c
@@ -54,5 +54,6 @@ int cmd_hash_impl(int ac, const char **av, int algo)
 		fwrite(hash, 1, algop->rawsz, stdout);
 	else
 		puts(hash_to_hex_algop(hash, algop));
+	free(buffer);
 	return 0;
 }
diff --git a/t/helper/test-json-writer.c b/t/helper/test-json-writer.c
index 37c452535f..8c3edacc00 100644
--- a/t/helper/test-json-writer.c
+++ b/t/helper/test-json-writer.c
@@ -181,12 +181,18 @@ static struct json_writer nest1 = JSON_WRITER_INIT;
 
 static void make_nest1(int pretty)
 {
+	make_obj1(0);
+	make_arr1(0);
+
 	jw_object_begin(&nest1, pretty);
 	{
 		jw_object_sub_jw(&nest1, "obj1", &obj1);
 		jw_object_sub_jw(&nest1, "arr1", &arr1);
 	}
 	jw_end(&nest1);
+
+	jw_release(&obj1);
+	jw_release(&arr1);
 }
 
 static char *expect_inline1 =
@@ -313,6 +319,9 @@ static void make_mixed1(int pretty)
 		jw_object_sub_jw(&mixed1, "arr1", &arr1);
 	}
 	jw_end(&mixed1);
+
+	jw_release(&obj1);
+	jw_release(&arr1);
 }
 
 static void cmp(const char *test, const struct json_writer *jw, const char *exp)
@@ -325,8 +334,8 @@ static void cmp(const char *test, const struct json_writer *jw, const char *exp)
 	exit(1);
 }
 
-#define t(v) do { make_##v(0); cmp(#v, &v, expect_##v); } while (0)
-#define p(v) do { make_##v(1); cmp(#v, &v, pretty_##v); } while (0)
+#define t(v) do { make_##v(0); cmp(#v, &v, expect_##v); jw_release(&v); } while (0)
+#define p(v) do { make_##v(1); cmp(#v, &v, pretty_##v); jw_release(&v); } while (0)
 
 /*
  * Run some basic regression tests with some known patterns.
@@ -381,7 +390,6 @@ static int unit_tests(void)
 
 	/* mixed forms */
 	t(mixed1);
-	jw_init(&mixed1);
 	p(mixed1);
 
 	return 0;
@@ -544,7 +552,7 @@ static int scripted(void)
 
 	printf("%s\n", jw.json.buf);
 
-	strbuf_release(&jw.json);
+	jw_release(&jw);
 	return 0;
 }
 
diff --git a/t/helper/test-path-utils.c b/t/helper/test-path-utils.c
index 229ed416b0..d20e1b7a18 100644
--- a/t/helper/test-path-utils.c
+++ b/t/helper/test-path-utils.c
@@ -296,9 +296,8 @@ int cmd__path_utils(int argc, const char **argv)
 	if (argc == 3 && !strcmp(argv[1], "normalize_path_copy")) {
 		char *buf = xmallocz(strlen(argv[2]));
 		int rv = normalize_path_copy(buf, argv[2]);
-		if (rv)
-			buf = "++failed++";
-		puts(buf);
+		puts(rv ? "++failed++" : buf);
+		free(buf);
 		return 0;
 	}
 
@@ -356,7 +355,10 @@ int cmd__path_utils(int argc, const char **argv)
 		int nongit_ok;
 		setup_git_directory_gently(&nongit_ok);
 		while (argc > 3) {
-			puts(prefix_path(prefix, prefix_len, argv[3]));
+			char *pfx = prefix_path(prefix, prefix_len, argv[3]);
+
+			puts(pfx);
+			free(pfx);
 			argc--;
 			argv++;
 		}
@@ -366,6 +368,7 @@ int cmd__path_utils(int argc, const char **argv)
 	if (argc == 4 && !strcmp(argv[1], "strip_path_suffix")) {
 		char *prefix = strip_path_suffix(argv[2], argv[3]);
 		printf("%s\n", prefix ? prefix : "(null)");
+		free(prefix);
 		return 0;
 	}
 
diff --git a/t/helper/test-ref-store.c b/t/helper/test-ref-store.c
index 9646d85fc8..4d18bfb1ca 100644
--- a/t/helper/test-ref-store.c
+++ b/t/helper/test-ref-store.c
@@ -96,6 +96,7 @@ static const char **get_store(const char **argv, struct ref_store **refs)
 			die("no such worktree: %s", gitdir);
 
 		*refs = get_worktree_ref_store(*p);
+		free_worktrees(worktrees);
 	} else
 		die("unknown backend %s", argv[0]);
 
diff --git a/t/helper/test-regex.c b/t/helper/test-regex.c
index d6f28ca8d1..bd871a735b 100644
--- a/t/helper/test-regex.c
+++ b/t/helper/test-regex.c
@@ -34,6 +34,7 @@ static int test_regex_bug(void)
 	if (m[0].rm_so == 3) /* matches '\n' when it should not */
 		die("regex bug confirmed: re-build git with NO_REGEX=1");
 
+	regfree(&r);
 	return 0;
 }
 
@@ -94,18 +95,20 @@ int cmd__regex(int argc, const char **argv)
 		die("failed regcomp() for pattern '%s' (%s)", pat, errbuf);
 	}
 	if (!str)
-		return 0;
+		goto cleanup;
 
 	ret = regexec(&r, str, 1, m, 0);
 	if (ret) {
 		if (silent || ret == REG_NOMATCH)
-			return ret;
+			goto cleanup;
 
 		regerror(ret, &r, errbuf, sizeof(errbuf));
 		die("failed regexec() for subject '%s' (%s)", str, errbuf);
 	}
 
-	return 0;
+cleanup:
+	regfree(&r);
+	return ret;
 usage:
 	usage("\ttest-tool regex --bug\n"
 	      "\ttest-tool regex [--silent] <pattern>\n"
diff --git a/t/helper/test-scrap-cache-tree.c b/t/helper/test-scrap-cache-tree.c
index 393f1604ff..026c802479 100644
--- a/t/helper/test-scrap-cache-tree.c
+++ b/t/helper/test-scrap-cache-tree.c
@@ -12,6 +12,7 @@ int cmd__scrap_cache_tree(int ac, const char **av)
 	hold_locked_index(&index_lock, LOCK_DIE_ON_ERROR);
 	if (read_cache() < 0)
 		die("unable to read index file");
+	cache_tree_free(&active_cache_tree);
 	active_cache_tree = NULL;
 	if (write_locked_index(&the_index, &index_lock, COMMIT_LOCK))
 		die("unable to write index file");
diff --git a/t/helper/test-urlmatch-normalization.c b/t/helper/test-urlmatch-normalization.c
index 8f4d67e646..86edd454f5 100644
--- a/t/helper/test-urlmatch-normalization.c
+++ b/t/helper/test-urlmatch-normalization.c
@@ -5,8 +5,9 @@
 int cmd__urlmatch_normalization(int argc, const char **argv)
 {
 	const char usage[] = "test-tool urlmatch-normalization [-p | -l] <url1> | <url1> <url2>";
-	char *url1, *url2;
+	char *url1 = NULL, *url2 = NULL;
 	int opt_p = 0, opt_l = 0;
+	int ret = 0;
 
 	/*
 	 * For one url, succeed if url_normalize succeeds on it, fail otherwise.
@@ -39,7 +40,7 @@ int cmd__urlmatch_normalization(int argc, const char **argv)
 			printf("%s\n", url1);
 		if (opt_l)
 			printf("%u\n", (unsigned)info.url_len);
-		return 0;
+		goto cleanup;
 	}
 
 	if (opt_p || opt_l)
@@ -47,5 +48,9 @@ int cmd__urlmatch_normalization(int argc, const char **argv)
 
 	url1 = url_normalize(argv[1], NULL);
 	url2 = url_normalize(argv[2], NULL);
-	return (url1 && url2 && !strcmp(url1, url2)) ? 0 : 1;
+	ret = (url1 && url2 && !strcmp(url1, url2)) ? 0 : 1;
+cleanup:
+	free(url1);
+	free(url2);
+	return ret;
 }
diff --git a/t/t0015-hash.sh b/t/t0015-hash.sh
index 086822fc45..0a087a1983 100755
--- a/t/t0015-hash.sh
+++ b/t/t0015-hash.sh
@@ -1,8 +1,9 @@
 #!/bin/sh
 
 test_description='test basic hash implementation'
-. ./test-lib.sh
 
+TEST_PASSES_SANITIZE_LEAK=true
+. ./test-lib.sh
 
 test_expect_success 'test basic SHA-1 hash values' '
 	test-tool sha1 </dev/null >actual &&
diff --git a/t/t0019-json-writer.sh b/t/t0019-json-writer.sh
index 3b0c336b38..19a730c29e 100755
--- a/t/t0019-json-writer.sh
+++ b/t/t0019-json-writer.sh
@@ -1,6 +1,8 @@
 #!/bin/sh
 
 test_description='test json-writer JSON generation'
+
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_expect_success 'unit test of json-writer routines' '
diff --git a/t/t0060-path-utils.sh b/t/t0060-path-utils.sh
index aa35350b6f..1f2007e62b 100755
--- a/t/t0060-path-utils.sh
+++ b/t/t0060-path-utils.sh
@@ -5,6 +5,7 @@
 
 test_description='Test various path utilities'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 norm_path() {
diff --git a/t/t0090-cache-tree.sh b/t/t0090-cache-tree.sh
index 9067572648..d8e2fc42e1 100755
--- a/t/t0090-cache-tree.sh
+++ b/t/t0090-cache-tree.sh
@@ -5,6 +5,8 @@ test_description="Test whether cache-tree is properly updated
 Tests whether various commands properly update and/or rewrite the
 cache-tree extension.
 "
+
+TEST_PASSES_SANITIZE_LEAK=true
  . ./test-lib.sh
 
 cmp_cache_tree () {
diff --git a/t/t0095-bloom.sh b/t/t0095-bloom.sh
index 5945973552..daeb4a5e3e 100755
--- a/t/t0095-bloom.sh
+++ b/t/t0095-bloom.sh
@@ -67,7 +67,7 @@ test_expect_success 'compute bloom key for test string 2' '
 	test_cmp expect actual
 '
 
-test_expect_success 'get bloom filters for commit with no changes' '
+test_expect_success !SANITIZE_LEAK 'get bloom filters for commit with no changes' '
 	git init &&
 	git commit --allow-empty -m "c0" &&
 	cat >expect <<-\EOF &&
diff --git a/t/t0110-urlmatch-normalization.sh b/t/t0110-urlmatch-normalization.sh
index 4dc9fecf72..12d817fbd3 100755
--- a/t/t0110-urlmatch-normalization.sh
+++ b/t/t0110-urlmatch-normalization.sh
@@ -1,6 +1,8 @@
 #!/bin/sh
 
 test_description='urlmatch URL normalization'
+
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 # The base name of the test url files
diff --git a/t/t5303-pack-corruption-resilience.sh b/t/t5303-pack-corruption-resilience.sh
index 41e6dc4dcf..2926e8dfc4 100755
--- a/t/t5303-pack-corruption-resilience.sh
+++ b/t/t5303-pack-corruption-resilience.sh
@@ -4,6 +4,8 @@
 #
 
 test_description='resilience to pack corruptions with redundant objects'
+
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 # Note: the test objects are created with knowledge of their pack encoding
diff --git a/t/t5308-pack-detect-duplicates.sh b/t/t5308-pack-detect-duplicates.sh
index 693b2411c8..655cafa054 100755
--- a/t/t5308-pack-detect-duplicates.sh
+++ b/t/t5308-pack-detect-duplicates.sh
@@ -1,6 +1,8 @@
 #!/bin/sh
 
 test_description='handling of duplicate objects in incoming packfiles'
+
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-pack.sh
 
diff --git a/t/t5309-pack-delta-cycles.sh b/t/t5309-pack-delta-cycles.sh
index 55b787630f..4e910c5b9d 100755
--- a/t/t5309-pack-delta-cycles.sh
+++ b/t/t5309-pack-delta-cycles.sh
@@ -1,6 +1,8 @@
 #!/bin/sh
 
 test_description='test index-pack handling of delta cycles in packfiles'
+
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-pack.sh
 
diff --git a/t/t5321-pack-large-objects.sh b/t/t5321-pack-large-objects.sh
index 8a56d98a0e..70770fe274 100755
--- a/t/t5321-pack-large-objects.sh
+++ b/t/t5321-pack-large-objects.sh
@@ -6,6 +6,8 @@
 test_description='git pack-object with "large" deltas
 
 '
+
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-pack.sh
 
diff --git a/t/t7812-grep-icase-non-ascii.sh b/t/t7812-grep-icase-non-ascii.sh
index ac7be54714..31c66b63c2 100755
--- a/t/t7812-grep-icase-non-ascii.sh
+++ b/t/t7812-grep-icase-non-ascii.sh
@@ -2,6 +2,7 @@
 
 test_description='grep icase on non-English locales'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./lib-gettext.sh
 
 doalarm () {