parport: Clean up resources correctly when parport_register_port() fails

The smatch warns about uncleaned resources in case the
parport_register_port() fails:

  parport_register_port() warn: '&tmp->full_list' not removed from list

This is indeed an issue introduced when converting code to use
kasprintf(). However, the whole kasprintf() dance in this case
is not needed as dev_set_name() can handle the formatted input
and produces the same result. So, the solution is to delegate
name forming to the dev_set_name() and make device_register()
error path to deal with error handling (via put_device() call).

Fixes: 8d8ae17eb0de ("parport: Use kasprintf() instead of fixed buffer formatting")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202310180809.hepZB9k6-lkp@intel.com/
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20231018145948.1367648-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 3 insertions, 7 deletions

diff --git a/drivers/parport/share.c b/drivers/parport/share.c
index a9a9cb0477ea..048a459ce4b0 100644
--- a/drivers/parport/share.c
+++ b/drivers/parport/share.c
@@ -361,7 +361,6 @@ static void free_port(struct device *dev)
 		kfree(port->probe_info[d].description);
 	}
 
-	kfree(port->name);
 	kfree(port);
 }
 
@@ -479,16 +478,13 @@ struct parport *parport_register_port(unsigned long base, int irq, int dma,
 	/*
 	 * Now that the portnum is known finish doing the Init.
 	 */
-	tmp->name = kasprintf(GFP_KERNEL, "parport%d", tmp->portnum);
-	if (!tmp->name) {
-		kfree(tmp);
-		return NULL;
-	}
-	dev_set_name(&tmp->bus_dev, tmp->name);
+	dev_set_name(&tmp->bus_dev, "parport%d", tmp->portnum);
 	tmp->bus_dev.bus = &parport_bus_type;
 	tmp->bus_dev.release = free_port;
 	tmp->bus_dev.type = &parport_device_type;
 
+	tmp->name = dev_name(&tmp->bus_dev);
+
 	for (device = 0; device < 5; device++)
 		/* assume the worst */
 		tmp->probe_info[device].class = PARPORT_CLASS_LEGACY;