| Message ID | 20230922074631.9408-1-dinghao.liu@zju.edu.cn (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2] scsi: zfcp: Fix a double put in zfcp_port_enqueue | expand |
On 9/22/23 00:46, Dinghao Liu wrote: > diff --git a/drivers/s390/scsi/zfcp_aux.c b/drivers/s390/scsi/zfcp_aux.c > index df782646e856..ad0ef9546501 100644 > --- a/drivers/s390/scsi/zfcp_aux.c > +++ b/drivers/s390/scsi/zfcp_aux.c > @@ -552,7 +552,7 @@ struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn, > > if (device_register(&port->dev)) { > put_device(&port->dev); > - goto err_out; > + goto err_register; > } > > write_lock_irq(&adapter->port_list_lock); > @@ -565,5 +565,6 @@ struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn, > > err_out: > zfcp_ccw_adapter_put(adapter); > +err_register: > return ERR_PTR(retval); > } goto labels should be named after the code below the goto label instead of reflecting where the goto statement comes from. Thanks, Bart.
diff --git a/drivers/s390/scsi/zfcp_aux.c b/drivers/s390/scsi/zfcp_aux.c index df782646e856..ad0ef9546501 100644 --- a/drivers/s390/scsi/zfcp_aux.c +++ b/drivers/s390/scsi/zfcp_aux.c @@ -552,7 +552,7 @@ struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn, if (device_register(&port->dev)) { put_device(&port->dev); - goto err_out; + goto err_register; } write_lock_irq(&adapter->port_list_lock); @@ -565,5 +565,6 @@ struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn, err_out: zfcp_ccw_adapter_put(adapter); +err_register: return ERR_PTR(retval); }
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> --- Changelog: v2: -Improve the patch description. -Add a new label 'err_register' to unify code style. --- drivers/s390/scsi/zfcp_aux.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)