Previous commit 04b5b5cb0136 ("scsi: core: Fix possible memory leak if
device_add() fails") introduced a double free when device_add() failed.
When device_add() failed, the put_device(&rc->dev) is called, which will
call raid_component_release(), and this function will call
put_device(rc->dev.parent) and kfree(rc), but in the error path of
raid_component_release() above two functions are called again, so 'rc' are
freed twice.
We do not just revert the patch, since the memory allocated by
dev_set_name() is not released in the error path, it should be released
through calling put_device(&rc->dev) which will call kobject_cleanup(),
and the device name will be released in it. Though the commit 04b5b5cb0136
("scsi: core: Fix possible memory leak if device_add() fails") fixed the
memory leak, it didn't consider the double free problem. We removed
put_device(rc->dev.parent) and kfree(rc) in the error path, and we moved
put_device(&rc->dev) after rd->component-count--, since after
put_device(&rc->dev) is called, 'rc' is freed, so list_del(&rc->node)
cannot be called again.
Fixes: 04b5b5cb0136 ("scsi: core: Fix possible memory leak if device_add() fails")
Signed-off-by: Zhu Wang <wangzhu9@xxxxxxxxxx>
---
drivers/scsi/raid_class.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/scsi/raid_class.c b/drivers/scsi/raid_class.c
index 711252e52d8e..86ed1f66d749 100644
--- a/drivers/scsi/raid_class.c
+++ b/drivers/scsi/raid_class.c
@@ -248,11 +248,9 @@ int raid_component_add(struct raid_template *r,struct device *raid_dev,
return 0;
err_out:
- put_device(&rc->dev);
list_del(&rc->node);
rd->component_count--;
- put_device(component_dev);
- kfree(rc);
+ put_device(&rc->dev);
return err;
}
EXPORT_SYMBOL(raid_component_add);
--
2.34.1
