[PATCH v1 1/2] i2c: dev: check return value when calling dev_set_name()

From: Andy Shevchenko
Date: Mon Apr 11 2022 - 14:08:06 EST


If dev_set_name() fails, the dev_name() is null, check the return
value of dev_set_name() to avoid the null-ptr-deref.

Fixes: 1413ef638aba ("i2c: dev: Fix the race between the release of i2c_dev and cdev")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
drivers/i2c/i2c-dev.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
index cf5d049342ea..6fd2b6718b08 100644
--- a/drivers/i2c/i2c-dev.c
+++ b/drivers/i2c/i2c-dev.c
@@ -668,16 +668,21 @@ static int i2cdev_attach_adapter(struct device *dev, void *dummy)
i2c_dev->dev.class = i2c_dev_class;
i2c_dev->dev.parent = &adap->dev;
i2c_dev->dev.release = i2cdev_dev_release;
- dev_set_name(&i2c_dev->dev, "i2c-%d", adap->nr);
+
+ res = dev_set_name(&i2c_dev->dev, "i2c-%d", adap->nr);
+ if (res)
+ goto err_put_i2c_dev;

res = cdev_device_add(&i2c_dev->cdev, &i2c_dev->dev);
- if (res) {
- put_i2c_dev(i2c_dev, false);
- return res;
- }
+ if (res)
+ goto err_put_i2c_dev;

pr_debug("adapter [%s] registered as minor %d\n", adap->name, adap->nr);
return 0;
+
+err_put_i2c_dev:
+ put_i2c_dev(i2c_dev, false);
+ return res;
}

static int i2cdev_detach_adapter(struct device *dev, void *dummy)
--
2.35.1