[PATCH 2/2] regcache: Add test for bounds checking of regcache drop requests

[Mark Brown]

Validate that regcache_drop_region() rejects regions with a minimum
greater than the maximum.

Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
 drivers/base/regmap/regmap-kunit.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/drivers/base/regmap/regmap-kunit.c b/drivers/base/regmap/regmap-kunit.c
index c78772b660d6..c948219f46a3 100644
--- a/drivers/base/regmap/regmap-kunit.c
+++ b/drivers/base/regmap/regmap-kunit.c
@@ -1347,6 +1347,26 @@ static void cache_drop(struct kunit *test)
 	KUNIT_EXPECT_MEMEQ(test, &data->vals[param->from_reg], rval, sizeof(rval));
 }
 
+static void cache_drop_min_max(struct kunit *test)
+{
+	const struct regmap_test_param *param = test->param_value;
+	struct regmap *map;
+	struct regmap_config config;
+	struct regmap_ram_data *data;
+
+	config = test_regmap_config;
+	config.num_reg_defaults = BLOCK_TEST_SIZE;
+
+	map = gen_regmap(test, &config, &data);
+	KUNIT_ASSERT_FALSE(test, IS_ERR(map));
+	if (IS_ERR(map))
+		return;
+
+	/* Drop some registers */
+	KUNIT_EXPECT_EQ(test, -EINVAL, regcache_drop_region(map, param->from_reg + 5,
+							    param->from_reg + 3));
+}
+
 static void cache_drop_with_non_contiguous_ranges(struct kunit *test)
 {
 	const struct regmap_test_param *param = test->param_value;
@@ -2253,6 +2273,7 @@ static struct kunit_case regmap_test_cases[] = {
 	KUNIT_CASE_PARAM(cache_sync_readonly, real_cache_types_gen_params),
 	KUNIT_CASE_PARAM(cache_sync_patch, real_cache_types_gen_params),
 	KUNIT_CASE_PARAM(cache_drop, sparse_cache_types_gen_params),
+	KUNIT_CASE_PARAM(cache_drop_min_max, sparse_cache_types_gen_params),
 	KUNIT_CASE_PARAM(cache_drop_with_non_contiguous_ranges, sparse_cache_types_gen_params),
 	KUNIT_CASE_PARAM(cache_drop_all_and_sync_marked_dirty, sparse_cache_types_gen_params),
 	KUNIT_CASE_PARAM(cache_drop_all_and_sync_no_defaults, sparse_cache_types_gen_params),

-- 
2.47.3