usb: gadget: u_serial: add missing port entry locking

gserial_alloc_line() misses locking (for a release barrier) while resetting port entry on TTY allocation failure. Fix this. Cc: [email protected] Signed-off-by: Michał Mirosław <[email protected]> Reviewed-by: Greg Kroah-Hartman <[email protected]> Tested-by: Ladislav Michl <[email protected]> Signed-off-by: Felipe Balbi <[email protected]>
kmaincent · Oct 22, 2019 · daf82bd · daf82bd
1 parent 9ba3aca
commit daf82bd
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c
@@ -1239,8 +1239,10 @@ int gserial_alloc_line(unsigned char *line_num)
 				__func__, port_num, PTR_ERR(tty_dev));
 
 		ret = PTR_ERR(tty_dev);
+		mutex_lock(&ports[port_num].lock);
 		port = ports[port_num].port;
 		ports[port_num].port = NULL;
+		mutex_unlock(&ports[port_num].lock);
 		gserial_free_port(port);
 		goto err;
 	}