diff options
| author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2018-05-07 20:11:30 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-05-14 14:48:28 +0300 |
| commit | 9594b5be7ec110ed11acec58fa94f3f293668c85 (patch) | |
| tree | e6217d90327bbfde019b0182f46f30df93ea2abd /drivers/tty | |
| parent | 7722c24091c0fcd5041b12d4493064bdf8477098 (diff) | |
| download | linux-9594b5be7ec110ed11acec58fa94f3f293668c85.tar.xz | |
tty/serial: atmel: use port->name as name in request_irq()
I was puzzled while looking at /proc/interrupts and random things showed
up between reboots. This occurred more often but I realised it later. The
"correct" output should be:
|38: 11861 atmel-aic5 2 Level ttyS0
but I saw sometimes
|38: 6426 atmel-aic5 2 Level tty1
and accounted it wrongly as correct. This is use after free and the
former example randomly got the "old" pointer which pointed to the same
content. With SLAB_FREELIST_RANDOM and HARDENED I even got
|38: 7067 atmel-aic5 2 Level E=Started User Manager for UID 0
or other nonsense.
As it turns out the tty, pointer that is accessed in atmel_startup(), is
freed() before atmel_shutdown(). It seems to happen quite often that the
tty for ttyS0 is allocated and freed while ->shutdown is not invoked. I
don't do anything special - just a systemd boot :)
Use dev_name(&pdev->dev) as the IRQ name for request_irq(). This exists
as long as the driver is loaded so no use-after-free here.
Cc: stable@vger.kernel.org
Fixes: 761ed4a94582 ("tty: serial_core: convert uart_close to use tty_port_close")
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/atmel_serial.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index e287fe8f10fc..55b3eff148b1 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -1757,7 +1757,6 @@ static int atmel_startup(struct uart_port *port) { struct platform_device *pdev = to_platform_device(port->dev); struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); - struct tty_struct *tty = port->state->port.tty; int retval; /* @@ -1772,8 +1771,8 @@ static int atmel_startup(struct uart_port *port) * Allocate the IRQ */ retval = request_irq(port->irq, atmel_interrupt, - IRQF_SHARED | IRQF_COND_SUSPEND, - tty ? tty->name : "atmel_serial", port); + IRQF_SHARED | IRQF_COND_SUSPEND, + dev_name(&pdev->dev), port); if (retval) { dev_err(port->dev, "atmel_startup - Can't get irq\n"); return retval; |