From: Dinghao Liu <dinghao.liu@zju.edu.cn>
Date: Sat, 23 Sep 2023 18:37:23 +0800
Subject: scsi: zfcp: Fix a double put in zfcp_port_enqueue()
Git-commit: b481f644d9174670b385c3a699617052cd2a79d3
Patch-mainline: v6.6-rc5
References: git-fixes bsc#1216514
When device_register() fails, zfcp_port_release() will be called after
put_device(). As a result, zfcp_ccw_adapter_put() will be called twice: one
in zfcp_port_release() and one in the error path after device_register().
So the reference on the adapter object is doubly put, which may lead to a
premature free. Fix this by adjusting the error tag after
device_register().
Fixes: f3450c7b9172 ("[SCSI] zfcp: Replace local reference counting with common kref")
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Link: https://lore.kernel.org/r/20230923103723.10320-1-dinghao.liu@zju.edu.cn
Acked-by: Benjamin Block <bblock@linux.ibm.com>
Cc: stable@vger.kernel.org # v2.6.33+
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Miroslav Franc <mfranc@suse.cz>
---
drivers/s390/scsi/zfcp_aux.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/s390/scsi/zfcp_aux.c b/drivers/s390/scsi/zfcp_aux.c
index b044d3d51375..bbc9e134edbe 100644
--- a/drivers/s390/scsi/zfcp_aux.c
+++ b/drivers/s390/scsi/zfcp_aux.c
@@ -496,12 +496,12 @@ struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
if (port) {
put_device(&port->dev);
retval = -EEXIST;
- goto err_out;
+ goto err_put;
}
port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
if (!port)
- goto err_out;
+ goto err_put;
rwlock_init(&port->unit_list_lock);
INIT_LIST_HEAD(&port->unit_list);
@@ -524,7 +524,7 @@ struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
if (dev_set_name(&port->dev, "0x%016llx", (unsigned long long)wwpn)) {
kfree(port);
- goto err_out;
+ goto err_put;
}
retval = -EINVAL;
@@ -541,8 +541,9 @@ struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
return port;
-err_out:
+err_put:
zfcp_ccw_adapter_put(adapter);
+err_out:
return ERR_PTR(retval);
}