2024-04-11 10:38:40

by Richard Fitzgerald

Subject: [PATCH] regmap: kunit: Fix memory leaks in gen_regmap() and gen_raw_regmap()

- Use kunit_kcalloc() to allocate the defaults table so that it will be
freed when the test case ends.
- kfree() the buf and *data buffers on the error paths.
- Use kunit_add_action_or_reset() instead of kunit_add_action() so that
if it fails it will call regmap_exit().

Signed-off-by: Richard Fitzgerald <[email protected]>
---
drivers/base/regmap/regmap-kunit.c | 72 +++++++++++++++++++-----------
1 file changed, 45 insertions(+), 27 deletions(-)

diff --git a/drivers/base/regmap/regmap-kunit.c b/drivers/base/regmap/regmap-kunit.c
index 44265dc2313d..55d00e86c71c 100644
--- a/drivers/base/regmap/regmap-kunit.c
+++ b/drivers/base/regmap/regmap-kunit.c
@@ -145,9 +145,9 @@ static struct regmap *gen_regmap(struct kunit *test,
const struct regmap_test_param *param = test->param_value;
struct regmap_test_priv *priv = test->priv;
unsigned int *buf;
- struct regmap *ret;
+ struct regmap *ret = ERR_PTR(-ENOMEM);
size_t size;
- int i;
+ int i, error;
struct reg_default *defaults;

config->cache_type = param->cache;
@@ -172,15 +172,17 @@ static struct regmap *gen_regmap(struct kunit *test,

*data = kzalloc(sizeof(**data), GFP_KERNEL);
if (!(*data))
- return ERR_PTR(-ENOMEM);
+ goto out_free;
(*data)->vals = buf;

if (config->num_reg_defaults) {
- defaults = kcalloc(config->num_reg_defaults,
- sizeof(struct reg_default),
- GFP_KERNEL);
+ defaults = kunit_kcalloc(test,
+ config->num_reg_defaults,
+ sizeof(struct reg_default),
+ GFP_KERNEL);
if (!defaults)
- return ERR_PTR(-ENOMEM);
+ goto out_free;
+
config->reg_defaults = defaults;

for (i = 0; i < config->num_reg_defaults; i++) {
@@ -190,12 +192,19 @@ static struct regmap *gen_regmap(struct kunit *test,
}

ret = regmap_init_ram(priv->dev, config, *data);
- if (IS_ERR(ret)) {
- kfree(buf);
- kfree(*data);
- } else {
- kunit_add_action(test, regmap_exit_action, ret);
- }
+ if (IS_ERR(ret))
+ goto out_free;
+
+ /* This calls regmap_exit() on failure, which frees buf and *data */
+ error = kunit_add_action_or_reset(test, regmap_exit_action, ret);
+ if (error)
+ ret = ERR_PTR(error);
+
+ return ret;
+
+out_free:
+ kfree(buf);
+ kfree(*data);

return ret;
}
@@ -1490,9 +1499,9 @@ static struct regmap *gen_raw_regmap(struct kunit *test,
struct regmap_test_priv *priv = test->priv;
const struct regmap_test_param *param = test->param_value;
u16 *buf;
- struct regmap *ret;
+ struct regmap *ret = ERR_PTR(-ENOMEM);
size_t size = (config->max_register + 1) * config->reg_bits / 8;
- int i;
+ int i, error;
struct reg_default *defaults;

config->cache_type = param->cache;
@@ -1508,15 +1517,16 @@ static struct regmap *gen_raw_regmap(struct kunit *test,

*data = kzalloc(sizeof(**data), GFP_KERNEL);
if (!(*data))
- return ERR_PTR(-ENOMEM);
+ goto out_free;
(*data)->vals = (void *)buf;

config->num_reg_defaults = config->max_register + 1;
- defaults = kcalloc(config->num_reg_defaults,
- sizeof(struct reg_default),
- GFP_KERNEL);
+ defaults = kunit_kcalloc(test,
+ config->num_reg_defaults,
+ sizeof(struct reg_default),
+ GFP_KERNEL);
if (!defaults)
- return ERR_PTR(-ENOMEM);
+ goto out_free;
config->reg_defaults = defaults;

for (i = 0; i < config->num_reg_defaults; i++) {
@@ -1529,7 +1539,8 @@ static struct regmap *gen_raw_regmap(struct kunit *test,
defaults[i].def = be16_to_cpu(buf[i]);
break;
default:
- return ERR_PTR(-EINVAL);
+ ret = ERR_PTR(-EINVAL);
+ goto out_free;
}
}

@@ -1541,12 +1552,19 @@ static struct regmap *gen_raw_regmap(struct kunit *test,
config->num_reg_defaults = 0;

ret = regmap_init_raw_ram(priv->dev, config, *data);
- if (IS_ERR(ret)) {
- kfree(buf);
- kfree(*data);
- } else {
- kunit_add_action(test, regmap_exit_action, ret);
- }
+ if (IS_ERR(ret))
+ goto out_free;
+
+ /* This calls regmap_exit() on failure, which frees buf and *data */
+ error = kunit_add_action_or_reset(test, regmap_exit_action, ret);
+ if (error)
+ ret = ERR_PTR(error);
+
+ return ret;
+
+out_free:
+ kfree(buf);
+ kfree(*data);

return ret;
}
--
2.39.2

2024-04-11 11:31:03

by Markus Elfring

Subject: Re: [PATCH] regmap: kunit: Fix memory leaks in gen_regmap() and gen_raw_regmap()

…
> - kfree() the buf and *data buffers on the error paths.
…

Will development interests grow for scope-based resource management?


…
+++ b/drivers/base/regmap/regmap-kunit.c
@@ -145,9 +145,9 @@ static struct regmap *gen_regmap(struct kunit *test,
…
- struct regmap *ret;
+ struct regmap *ret = ERR_PTR(-ENOMEM);
…

How do you think about to use the statement “return ERR_PTR(-ENOMEM);” at the end
instead of the extra variable initialisation?


…
@@ -172,15 +172,17 @@ static struct regmap *gen_regmap(struct kunit *test,

*data = kzalloc(sizeof(**data), GFP_KERNEL);
if (!(*data))
- return ERR_PTR(-ENOMEM);
+ goto out_free;
…

I suggest to reconsider the label selection.

Regards,
Markus