uart_shutdown() invokes uart_port_lock(), which returns a reference of the uart_port object if increases the refcount of the uart_state object successfully or returns NULL if fails. However, uart_shutdown() don't take the return value of uart_port_lock() as the new uart_port object to "uport" and use the old "uport" instead to balance refcount in uart_port_unlock(), which may cause a redundant decrement of refcount occurred when the new "uport" equals to NULL and then cause a potential memory leak. Fix this issue by update the "uport" object to the return value of uart_port_lock() when invoking uart_port_lock(). Signed-off-by: Xiyu Yang <xiyuyang19@xxxxxxxxxxxx> Signed-off-by: Xin Tan <tanxin.ctf@xxxxxxxxx> --- drivers/tty/serial/serial_core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 57840cf90388..ab8756ef2b60 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -313,7 +313,7 @@ static void uart_shutdown(struct tty_struct *tty, struct uart_state *state) * console driver may need to allocate/free a debug object, which * can endup in printk() recursion. */ - uart_port_lock(state, flags); + uport = uart_port_lock(state, flags); xmit_buf = state->xmit.buf; state->xmit.buf = NULL; uart_port_unlock(uport, flags); -- 2.7.4
