Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Alex Dewar <alex.dewar90@gmail.com>
To:     mchehab@kernel.org
Cc:     Alex Dewar <alex.dewar90@gmail.com>,
        Dan Carpenter <dan.carpenter@oracle.com>,
        Sakari Ailus <sakari.ailus@linux.intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Linus Walleij <linus.walleij@linaro.org>,
        Alan Cox <alan@linux.intel.com>, linux-media@vger.kernel.org,
        devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org
Subject: [PATCH 1/3] staging: media: atomisp: Fix error path in lm3554_probe()
Date:   Sat, 17 Oct 2020 15:09:46 +0100
Message-Id: <20201017140950.15989-4-alex.dewar90@gmail.com>
In-Reply-To: <20201017140950.15989-1-alex.dewar90@gmail.com>
References: <20201017140950.15989-1-alex.dewar90@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

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@gmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
---
v5: Check for error, not success (Dan), but do it correctly cf. v4 :)
v4: Rebase
v3: No changes
v2: Fix a couple more leaks on error path (Dan)

 .../media/atomisp/i2c/atomisp-lm3554.c        | 55 +++++++++++--------
 1 file changed, 32 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..b38df022f880 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 +882,28 @@ 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)
+		goto err_del_timer;
+
+	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