[PATCH 7/8] i2c: stm32f7: fix reference leak when pm_runtime_get_sync fails

Qinglang Miao miaoqinglang at huawei.com
Tue Dec 1 04:31:45 EST 2020


The PM reference count is not expected to be incremented on
return in these stm32f7_i2c_xx serious functions.

However, pm_runtime_get_sync will increment the PM reference
count even failed. Forgetting to putting operation will result
in a reference leak here.

Replace it with pm_runtime_resume_and_get to keep usage
counter balanced.

Fixes: ea6dd25deeb5 ("i2c: stm32f7: add PM_SLEEP suspend/resume support")
Reported-by: Hulk Robot <hulkci at huawei.com>
Signed-off-by: Qinglang Miao <miaoqinglang at huawei.com>
---
 drivers/i2c/busses/i2c-stm32f7.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c
index f41f51a17..72fd5bdd6 100644
--- a/drivers/i2c/busses/i2c-stm32f7.c
+++ b/drivers/i2c/busses/i2c-stm32f7.c
@@ -1643,7 +1643,7 @@ static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap,
 	i2c_dev->msg_id = 0;
 	f7_msg->smbus = false;
 
-	ret = pm_runtime_get_sync(i2c_dev->dev);
+	ret = pm_runtime_resume_and_get(i2c_dev->dev);
 	if (ret < 0)
 		return ret;
 
@@ -1689,7 +1689,7 @@ static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
 	f7_msg->read_write = read_write;
 	f7_msg->smbus = true;
 
-	ret = pm_runtime_get_sync(dev);
+	ret = pm_runtime_resume_and_get(dev);
 	if (ret < 0)
 		return ret;
 
@@ -1790,7 +1790,7 @@ static int stm32f7_i2c_reg_slave(struct i2c_client *slave)
 	if (ret)
 		return ret;
 
-	ret = pm_runtime_get_sync(dev);
+	ret = pm_runtime_resume_and_get(dev);
 	if (ret < 0)
 		return ret;
 
@@ -1871,7 +1871,7 @@ static int stm32f7_i2c_unreg_slave(struct i2c_client *slave)
 
 	WARN_ON(!i2c_dev->slave[id]);
 
-	ret = pm_runtime_get_sync(i2c_dev->dev);
+	ret = pm_runtime_resume_and_get(i2c_dev->dev);
 	if (ret < 0)
 		return ret;
 
@@ -2268,7 +2268,7 @@ static int stm32f7_i2c_regs_backup(struct stm32f7_i2c_dev *i2c_dev)
 	int ret;
 	struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs;
 
-	ret = pm_runtime_get_sync(i2c_dev->dev);
+	ret = pm_runtime_resume_and_get(i2c_dev->dev);
 	if (ret < 0)
 		return ret;
 
@@ -2290,7 +2290,7 @@ static int stm32f7_i2c_regs_restore(struct stm32f7_i2c_dev *i2c_dev)
 	int ret;
 	struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs;
 
-	ret = pm_runtime_get_sync(i2c_dev->dev);
+	ret = pm_runtime_resume_and_get(i2c_dev->dev);
 	if (ret < 0)
 		return ret;
 
-- 
2.23.0




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