[PATCH] scsi: zfcp: fix use-after-free in zfcp_sysfs_port_remove_store

From: Qinglang Miao
Date: Fri Nov 20 2020 - 02:44:52 EST


kfree(port) is called in put_device(&port->dev) so that following
use would cause use-after-free bug.

the former put_device is redundant for device_unregister contains
put_device already. So just remove it to fix this.

Fixes: 83d4e1c33d93 ("[SCSI] zfcp: cleanup port sysfs attribute usage")
Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Qinglang Miao <miaoqinglang@xxxxxxxxxx>
---
drivers/s390/scsi/zfcp_sysfs.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/drivers/s390/scsi/zfcp_sysfs.c b/drivers/s390/scsi/zfcp_sysfs.c
index 8d9662e8b..06285e452 100644
--- a/drivers/s390/scsi/zfcp_sysfs.c
+++ b/drivers/s390/scsi/zfcp_sysfs.c
@@ -327,8 +327,6 @@ static ssize_t zfcp_sysfs_port_remove_store(struct device *dev,
list_del(&port->list);
write_unlock_irq(&adapter->port_list_lock);

- put_device(&port->dev);
-
zfcp_erp_port_shutdown(port, 0, "syprs_1");
device_unregister(&port->dev);
out:
--
2.23.0