[SCSI] zfcp: Handle failures during device allocation correctly

dev_set_name tries to allocate memory, so check the return value for
allocation failures. After dev_set_name succeeds, call device_register
as next step to be able to use put_device during error handling.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

1 files changed, 29 insertions, 36 deletions

diff --git a/drivers/s390/scsi/zfcp_aux.c b/drivers/s390/scsi/zfcp_aux.c
index a7954443ec19..1be6bf7e8ce6 100644
--- a/drivers/s390/scsi/zfcp_aux.c
+++ b/drivers/s390/scsi/zfcp_aux.c
@@ -274,6 +274,13 @@ struct zfcp_unit *zfcp_unit_enqueue(struct zfcp_port *port, u64 fcp_lun)
 {
         struct zfcp_unit *unit;
 
+        read_lock_irq(&zfcp_data.config_lock);
+        if (zfcp_get_unit_by_lun(port, fcp_lun)) {
+                read_unlock_irq(&zfcp_data.config_lock);
+                return ERR_PTR(-EINVAL);
+        }
+        read_unlock_irq(&zfcp_data.config_lock);
+
         unit = kzalloc(sizeof(struct zfcp_unit), GFP_KERNEL);
         if (!unit)
                 return ERR_PTR(-ENOMEM);
@@ -285,8 +292,11 @@ struct zfcp_unit *zfcp_unit_enqueue(struct zfcp_port *port, u64 fcp_lun)
         unit->port = port;
         unit->fcp_lun = fcp_lun;
 
-        dev_set_name(&unit->sysfs_device, "0x%016llx",
-                     (unsigned long long) fcp_lun);
+        if (dev_set_name(&unit->sysfs_device, "0x%016llx",
+                         (unsigned long long) fcp_lun)) {
+                kfree(unit);
+                return ERR_PTR(-ENOMEM);
+        }
         unit->sysfs_device.parent = &port->sysfs_device;
         unit->sysfs_device.release = zfcp_sysfs_unit_release;
         dev_set_drvdata(&unit->sysfs_device, unit);
@@ -302,13 +312,6 @@ struct zfcp_unit *zfcp_unit_enqueue(struct zfcp_port *port, u64 fcp_lun)
         unit->latencies.cmd.channel.min = 0xFFFFFFFF;
         unit->latencies.cmd.fabric.min = 0xFFFFFFFF;
 
-        read_lock_irq(&zfcp_data.config_lock);
-        if (zfcp_get_unit_by_lun(port, fcp_lun)) {
-                read_unlock_irq(&zfcp_data.config_lock);
-                goto err_out_free;
-        }
-        read_unlock_irq(&zfcp_data.config_lock);
-
         if (device_register(&unit->sysfs_device)) {
                 put_device(&unit->sysfs_device);
                 return ERR_PTR(-EINVAL);
@@ -317,7 +320,7 @@ struct zfcp_unit *zfcp_unit_enqueue(struct zfcp_port *port, u64 fcp_lun)
         if (sysfs_create_group(&unit->sysfs_device.kobj,
                                &zfcp_sysfs_unit_attrs)) {
                 device_unregister(&unit->sysfs_device);
-                return ERR_PTR(-EIO);
+                return ERR_PTR(-EINVAL);
         }
 
         zfcp_unit_get(unit);
@@ -332,10 +335,6 @@ struct zfcp_unit *zfcp_unit_enqueue(struct zfcp_port *port, u64 fcp_lun)
         zfcp_port_get(port);
 
         return unit;
-
-err_out_free:
-        kfree(unit);
-        return ERR_PTR(-EINVAL);
 }
 
 /**
@@ -642,7 +641,13 @@ struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
                                      u32 status, u32 d_id)
 {
         struct zfcp_port *port;
-        int retval;
+
+        read_lock_irq(&zfcp_data.config_lock);
+        if (zfcp_get_port_by_wwpn(adapter, wwpn)) {
+                read_unlock_irq(&zfcp_data.config_lock);
+                return ERR_PTR(-EINVAL);
+        }
+        read_unlock_irq(&zfcp_data.config_lock);
 
         port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
         if (!port)
@@ -663,31 +668,24 @@ struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
         atomic_set_mask(status | ZFCP_STATUS_COMMON_REMOVE, &port->status);
         atomic_set(&port->refcount, 0);
 
-        dev_set_name(&port->sysfs_device, "0x%016llx",
-                     (unsigned long long)wwpn);
+        if (dev_set_name(&port->sysfs_device, "0x%016llx",
+                         (unsigned long long)wwpn)) {
+                kfree(port);
+                return ERR_PTR(-ENOMEM);
+        }
         port->sysfs_device.parent = &adapter->ccw_device->dev;
-
         port->sysfs_device.release = zfcp_sysfs_port_release;
         dev_set_drvdata(&port->sysfs_device, port);
 
-        read_lock_irq(&zfcp_data.config_lock);
-        if (zfcp_get_port_by_wwpn(adapter, wwpn)) {
-                read_unlock_irq(&zfcp_data.config_lock);
-                goto err_out_free;
-        }
-        read_unlock_irq(&zfcp_data.config_lock);
-
         if (device_register(&port->sysfs_device)) {
                 put_device(&port->sysfs_device);
-                goto err_out;
+                return ERR_PTR(-EINVAL);
         }
 
-        retval = sysfs_create_group(&port->sysfs_device.kobj,
-                                    &zfcp_sysfs_port_attrs);
-
-        if (retval) {
+        if (sysfs_create_group(&port->sysfs_device.kobj,
+                               &zfcp_sysfs_port_attrs)) {
                 device_unregister(&port->sysfs_device);
-                goto err_out;
+                return ERR_PTR(-EINVAL);
         }
 
         zfcp_port_get(port);
@@ -701,11 +699,6 @@ struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
 
         zfcp_adapter_get(adapter);
         return port;
-
-err_out_free:
-        kfree(port);
-err_out:
-        return ERR_PTR(-EINVAL);
 }
 
 /**