[PATCH 5.12 556/677] i2c: cadence: fix reference leak when pm_runtime_get_sync fails

From: Greg Kroah-Hartman
Date: Wed May 12 2021 - 15:10:31 EST


From: Qinglang Miao <miaoqinglang@xxxxxxxxxx>

[ Upstream commit 23ceb8462dc6f4b4decdb5536a7e5fc477cdf0b6 ]

The PM reference count is not expected to be incremented on
return in functions cdns_i2c_master_xfer and cdns_reg_slave.

However, pm_runtime_get_sync will increment pm usage counter
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: 7fa32329ca03 ("i2c: cadence: Move to sensible power management")
Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Qinglang Miao <miaoqinglang@xxxxxxxxxx>
Signed-off-by: Wolfram Sang <wsa@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/i2c/busses/i2c-cadence.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-cadence.c b/drivers/i2c/busses/i2c-cadence.c
index e4b7f2a951ad..e8eae8725900 100644
--- a/drivers/i2c/busses/i2c-cadence.c
+++ b/drivers/i2c/busses/i2c-cadence.c
@@ -789,7 +789,7 @@ static int cdns_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
bool change_role = false;
#endif

- ret = pm_runtime_get_sync(id->dev);
+ ret = pm_runtime_resume_and_get(id->dev);
if (ret < 0)
return ret;

@@ -911,7 +911,7 @@ static int cdns_reg_slave(struct i2c_client *slave)
if (slave->flags & I2C_CLIENT_TEN)
return -EAFNOSUPPORT;

- ret = pm_runtime_get_sync(id->dev);
+ ret = pm_runtime_resume_and_get(id->dev);
if (ret < 0)
return ret;

--
2.30.2