Commit a5a2b130 authored Sep 13, 2016 by Andy Shevchenko Committed by Greg Kroah-Hartman Sep 15, 2016

serial: core: fix potential NULL pointer dereference



The commit 761ed4a9 ("tty: serial_core: convert uart_close to use
tty_port_close") refactored uart_close() to use tty_port_close().  At the same
time it introduced a potential NULL pointer dereference. Rearrange the code to
avoid kernel crash.

Fixes: 761ed4a9 ("tty: serial_core: convert uart_close to use tty_port_close")
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 0ae9fdef

drivers/tty/serial/serial_core.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -1484,15 +1484,15 @@ static void uart_tty_port_shutdown(struct tty_port *port)
		struct uart_state *state = container_of(port, struct uart_state, port);
		struct uart_port *uport = uart_port_check(state);

		spin_lock_irq(&uport->lock);
		/*
		* At this point, we stop accepting input. To do this, we
		* disable the receive line status interrupts.
		*/
		WARN(!uport, "detached port still initialized!\n");
		if (WARN(!uport, "detached port still initialized!\n"))
		return;

		spin_lock_irq(&uport->lock);
		uport->ops->stop_rx(uport);

		spin_unlock_irq(&uport->lock);

		uart_port_shutdown(port);