The kobject_create_and_add() call in genhd_device_init() may return NULL
if memory allocation fails, but the return value was not being checked.
This could lead to NULL pointer dereferences in subsequent calls to
sysfs_create_link() and sysfs_remove_link() which use block_depr.

Add proper error checking and cleanup path to handle the case when
kobject_create_and_add() fails.

Fixes: 721da5cee9d4 ("driver core: remove CONFIG_SYSFS_DEPRECATED
	and CONFIG_SYSFS_DEPRECATED_V2")
Signed-off-by: Li Jun <lijun01@kylinos.cn>
---
 block/genhd.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/block/genhd.c b/block/genhd.c
index 7d4ee5972338..60569d59cd53 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -1005,7 +1005,15 @@ static int __init genhd_device_init(void)
 
 	/* create top-level block dir */
 	block_depr = kobject_create_and_add("block", NULL);
+	if (!block_depr) {
+		error = -ENOMEM;
+		goto out_class_unregister;
+	}
 	return 0;
+
+out_class_unregister:
+	class_unregister(&block_class);
+	return error;
 }
 
 subsys_initcall(genhd_device_init);
-- 
2.25.1