On Tue, Jul 17, 2018 at 10:58 AM, Geert Uytterhoeven <[email protected]> wrote: > sci_request_irq() checks port->irqstr[j] for a NULL pointer, to decide > if a fallback interrupt name string should be allocated or not. > > While this string is freed during port shutdown, the pointer is not > zeroed. Hence on a subsequent startup of the port, it will still be > pointing to the freed memory, leading to e.g. > > WARNING: CPU: 0 PID: 404 at fs/proc/generic.c:388 __proc_create+0xbc/0x260 > name len 0 > > or to a crash (the latter is more likely with CONFIG_DEBUG_SLAB=y, due > to the poisoning of freed memory). > > Instead of zeroeing the pointer at multiple places, preinitialize > port->irqstr[j] to zero to fix this. > > Fixes: 8b0bbd956228ae87 ("serial: sh-sci: Add support for R7S9210") > Signed-off-by: Geert Uytterhoeven <[email protected]> > --- > drivers/tty/serial/sh-sci.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c > index 5808edfe3f7be404..f8e53ac5c17dfb94 100644 > --- a/drivers/tty/serial/sh-sci.c > +++ b/drivers/tty/serial/sh-sci.c > @@ -1872,6 +1872,7 @@ static int sci_request_irq(struct sci_port *port) > } > > desc = sci_irq_desc + i; > + port->irqstr[j] = NULL; > if (SCIx_TEIDRI_IRQ_EXISTS(port)) { > /* > * ERI and BRI are muxed, just register ERI and > -- > 2.17.1 >
Reviewed-by: Ulrich Hecht <[email protected]> CU Uli
