[PATCH v2] staging: media: atomisp: Fix error path in lm3554_probe()

From: Alex Dewar
Date: Thu Sep 03 2020 - 14:25:18 EST


The error path for lm3554_probe() contains a number of bugs, including:
* resource leaks
* jumping to error labels out of sequence
* not setting the return value appropriately

Fix it up and give the labels more memorable names.

This issue has existed since the code was originally contributed in
commit a49d25364dfb ("staging/atomisp: Add support for the Intel IPU v2"),
although the code was subsequently removed altogether and then
reinstated with commit ad85094b293e ("Revert "media: staging: atomisp: Remove driver"").

Addresses-Coverity: 1496802 ("Resource leaks")
Fixes: a49d25364dfb ("staging/atomisp: Add support for the Intel IPU v2")
Signed-off-by: Alex Dewar <alex.dewar90@xxxxxxxxx>
---
.../media/atomisp/i2c/atomisp-lm3554.c | 53 +++++++++++--------
1 file changed, 30 insertions(+), 23 deletions(-)

diff --git a/drivers/staging/media/atomisp/i2c/atomisp-lm3554.c b/drivers/staging/media/atomisp/i2c/atomisp-lm3554.c
index 7ca7378b1859..cca10a4c2db0 100644
--- a/drivers/staging/media/atomisp/i2c/atomisp-lm3554.c
+++ b/drivers/staging/media/atomisp/i2c/atomisp-lm3554.c
@@ -833,7 +833,6 @@ static void *lm3554_platform_data_func(struct i2c_client *client)

static int lm3554_probe(struct i2c_client *client)
{
- int err = 0;
struct lm3554 *flash;
unsigned int i;
int ret;
@@ -843,36 +842,38 @@ static int lm3554_probe(struct i2c_client *client)
return -ENOMEM;

flash->pdata = lm3554_platform_data_func(client);
- if (IS_ERR(flash->pdata))
- return PTR_ERR(flash->pdata);
+ if (IS_ERR(flash->pdata)) {
+ ret = PTR_ERR(flash->pdata);
+ goto err_free_flash;
+ }

v4l2_i2c_subdev_init(&flash->sd, client, &lm3554_ops);
flash->sd.internal_ops = &lm3554_internal_ops;
flash->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
flash->mode = ATOMISP_FLASH_MODE_OFF;
flash->timeout = LM3554_MAX_TIMEOUT / LM3554_TIMEOUT_STEPSIZE - 1;
- ret =
- v4l2_ctrl_handler_init(&flash->ctrl_handler,
- ARRAY_SIZE(lm3554_controls));
+ ret = v4l2_ctrl_handler_init(&flash->ctrl_handler,
+ ARRAY_SIZE(lm3554_controls));
if (ret) {
- dev_err(&client->dev, "error initialize a ctrl_handler.\n");
- goto fail2;
+ dev_err(&client->dev, "error initializing ctrl_handler");
+ goto err_unregister_sd;
}

for (i = 0; i < ARRAY_SIZE(lm3554_controls); i++)
v4l2_ctrl_new_custom(&flash->ctrl_handler, &lm3554_controls[i],
NULL);

- if (flash->ctrl_handler.error) {
- dev_err(&client->dev, "ctrl_handler error.\n");
- goto fail2;
+ ret = flash->ctrl_handler.error;
+ if (ret) {
+ dev_err(&client->dev, "ctrl_handler error");
+ goto err_free_ctrl_handler;
}

flash->sd.ctrl_handler = &flash->ctrl_handler;
- err = media_entity_pads_init(&flash->sd.entity, 0, NULL);
- if (err) {
- dev_err(&client->dev, "error initialize a media entity.\n");
- goto fail1;
+ ret = media_entity_pads_init(&flash->sd.entity, 0, NULL);
+ if (ret) {
+ dev_err(&client->dev, "error initializing media entity");
+ goto err_free_ctrl_handler;
}

flash->sd.entity.function = MEDIA_ENT_F_FLASH;
@@ -881,20 +882,26 @@ static int lm3554_probe(struct i2c_client *client)

timer_setup(&flash->flash_off_delay, lm3554_flash_off_delay, 0);

- err = lm3554_gpio_init(client);
- if (err) {
+ ret = lm3554_gpio_init(client);
+ if (ret) {
dev_err(&client->dev, "gpio request/direction_output fail");
- goto fail2;
+ goto err_del_timer;
}
- return atomisp_register_i2c_module(&flash->sd, NULL, LED_FLASH);
-fail2:
+
+ ret = atomisp_register_i2c_module(&flash->sd, NULL, LED_FLASH);
+ if (!ret)
+ return 0;
+
+err_del_timer:
+ del_timer_sync(&flash->flash_off_delay);
media_entity_cleanup(&flash->sd.entity);
+err_free_ctrl_handler:
v4l2_ctrl_handler_free(&flash->ctrl_handler);
-fail1:
+err_unregister_sd:
v4l2_device_unregister_subdev(&flash->sd);
+err_free_flash:
kfree(flash);
-
- return err;
+ return ret;
}

static int lm3554_remove(struct i2c_client *client)
--
2.28.0