In sas_port_add(), the return value of transport_add_device() is not checked. As a result, it causes null-ptr-deref while removing device, because transport_remove_device() is called to remove the device that was not added. Unable to handle kernel NULL pointer dereference at virtual address 0000000000000108 pc : device_del+0x54/0x3d0 lr : device_del+0x37c/0x3d0 Call trace: device_del+0x54/0x3d0 attribute_container_class_device_del+0x28/0x38 transport_remove_classdev+0x6c/0x80 attribute_container_device_trigger+0x108/0x110 transport_remove_device+0x28/0x38 sas_port_delete+0x110/0x148 [scsi_transport_sas] do_sas_phy_delete+0x78/0x80 [scsi_transport_sas] device_for_each_child+0x68/0xb0 sas_remove_children+0x30/0x50 [scsi_transport_sas] sas_rphy_remove+0x38/0x78 [scsi_transport_sas] sas_port_delete+0x30/0x148 [scsi_transport_sas] do_sas_phy_delete+0x78/0x80 [scsi_transport_sas] device_for_each_child+0x68/0xb0 sas_remove_children+0x30/0x50 [scsi_transport_sas] sas_remove_host+0x20/0x38 [scsi_transport_sas] scsih_remove+0xd8/0x420 [mpt3sas] Fix this by checking and handling return value of transport_add_device() in sas_port_add(). Fixes: 65c92b09acf0 ("[SCSI] scsi_transport_sas: introduce a sas_port entity") Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx> --- drivers/scsi/scsi_transport_sas.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/scsi_transport_sas.c b/drivers/scsi/scsi_transport_sas.c index accc0afa8f77..e090486258a5 100644 --- a/drivers/scsi/scsi_transport_sas.c +++ b/drivers/scsi/scsi_transport_sas.c @@ -959,7 +959,11 @@ int sas_port_add(struct sas_port *port) if (error) return error; - transport_add_device(&port->dev); + error = transport_add_device(&port->dev); + if (error) { + device_del(&port->dev); + return error; + } transport_configure_device(&port->dev); return 0; -- 2.25.1