lkml.org 
[lkml]   [2009]   [Dec]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [Regression, 2.6.33-rc1->current git] NULL pointer in usb_serial_probe() introduced by the recent kfifo changes
Date
On Wednesday 23 December 2009, Stefani Seibold wrote:
> Am Dienstag, den 22.12.2009, 21:37 -0800 schrieb Greg KH:
> > On Wed, Dec 23, 2009 at 02:51:31AM +0100, Rafael J. Wysocki wrote:
> > > Hi,
> > >
> > > Something like the patch below is necessary to fix a new NULL pointer deref
> > > in usb_serial_probe() that appeared after the recent kfifo changes (in short,
> > > the kfifo changes modified the semantics of kfifo_alloc() that
> > > usb_serial_probe() reiled on).
> >
> > What semantic changed? I thought that the kfifo patches came with
> > patches that also fixed up any changed that were needed. What went
> > wrong here?
> >
>
> This one is a new user of the kfifo API, so it forget to port it to the
> new kfifo API.
>
> Please make the write_fifo in place. Here is my patch to fix the
> regression and full ported version.
>
> Stefani
>
> Signed-off-by: Stefani Seibold <stefani@seibold.net>

Tested-by: Rafael J. Wysocki <rjw@sisk.pl>

> ---
> drivers/usb/serial/generic.c | 12 ++++++------
> drivers/usb/serial/usb-serial.c | 5 ++---
> include/linux/usb/serial.h | 3 ++-
> 3 files changed, 10 insertions(+), 10 deletions(-)
>
> diff -u -N -r -p old/drivers/usb/serial/generic.c new/drivers/usb/serial/generic.c
> --- old/drivers/usb/serial/generic.c 2009-12-23 08:54:06.966476248 +0100
> +++ new/drivers/usb/serial/generic.c 2009-12-23 09:06:25.778474708 +0100
> @@ -276,7 +276,7 @@ static int usb_serial_generic_write_star
> if (port->write_urb_busy)
> start_io = false;
> else {
> - start_io = (kfifo_len(port->write_fifo) != 0);
> + start_io = (kfifo_len(&port->write_fifo) != 0);
> port->write_urb_busy = start_io;
> }
> spin_unlock_irqrestore(&port->lock, flags);
> @@ -285,7 +285,7 @@ static int usb_serial_generic_write_star
> return 0;
>
> data = port->write_urb->transfer_buffer;
> - count = kfifo_out_locked(port->write_fifo, data, port->bulk_out_size, &port->lock);
> + count = kfifo_out_locked(&port->write_fifo, data, port->bulk_out_size, &port->lock);
> usb_serial_debug_data(debug, &port->dev, __func__, count, data);
>
> /* set up our urb */
> @@ -345,7 +345,7 @@ int usb_serial_generic_write(struct tty_
> return usb_serial_multi_urb_write(tty, port,
> buf, count);
>
> - count = kfifo_in_locked(port->write_fifo, buf, count, &port->lock);
> + count = kfifo_in_locked(&port->write_fifo, buf, count, &port->lock);
> result = usb_serial_generic_write_start(port);
>
> if (result >= 0)
> @@ -370,7 +370,7 @@ int usb_serial_generic_write_room(struct
> (serial->type->max_in_flight_urbs -
> port->urbs_in_flight);
> } else if (serial->num_bulk_out)
> - room = port->write_fifo->size - kfifo_len(port->write_fifo);
> + room = kfifo_avail(&port->write_fifo);
> spin_unlock_irqrestore(&port->lock, flags);
>
> dbg("%s - returns %d", __func__, room);
> @@ -391,7 +391,7 @@ int usb_serial_generic_chars_in_buffer(s
> chars = port->tx_bytes_flight;
> spin_unlock_irqrestore(&port->lock, flags);
> } else if (serial->num_bulk_out)
> - chars = kfifo_len(port->write_fifo);
> + chars = kfifo_len(&port->write_fifo);
>
> dbg("%s - returns %d", __func__, chars);
> return chars;
> @@ -507,7 +507,7 @@ void usb_serial_generic_write_bulk_callb
> if (status) {
> dbg("%s - nonzero multi-urb write bulk status "
> "received: %d", __func__, status);
> - kfifo_reset(port->write_fifo);
> + kfifo_reset_out(&port->write_fifo);
> } else
> usb_serial_generic_write_start(port);
> }
> diff -u -N -r -p old/drivers/usb/serial/usb-serial.c new/drivers/usb/serial/usb-serial.c
> --- old/drivers/usb/serial/usb-serial.c 2009-12-23 08:54:23.204476351 +0100
> +++ new/drivers/usb/serial/usb-serial.c 2009-12-23 09:06:39.664475312 +0100
> @@ -595,8 +595,7 @@ static void port_release(struct device *
> usb_free_urb(port->write_urb);
> usb_free_urb(port->interrupt_in_urb);
> usb_free_urb(port->interrupt_out_urb);
> - if (!IS_ERR(port->write_fifo) && port->write_fifo)
> - kfifo_free(port->write_fifo);
> + kfifo_free(&port->write_fifo);
> kfree(port->bulk_in_buffer);
> kfree(port->bulk_out_buffer);
> kfree(port->interrupt_in_buffer);
> @@ -939,7 +938,7 @@ int usb_serial_probe(struct usb_interfac
> dev_err(&interface->dev, "No free urbs available\n");
> goto probe_error;
> }
> - if (kfifo_alloc(port->write_fifo, PAGE_SIZE, GFP_KERNEL))
> + if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
> goto probe_error;
> buffer_size = le16_to_cpu(endpoint->wMaxPacketSize);
> port->bulk_out_size = buffer_size;
> diff -u -N -r -p old/include/linux/usb/serial.h new/include/linux/usb/serial.h
> --- old/include/linux/usb/serial.h 2009-12-23 08:54:34.368476110 +0100
> +++ new/include/linux/usb/serial.h 2009-12-23 09:06:32.870725683 +0100
> @@ -16,6 +16,7 @@
> #include <linux/kref.h>
> #include <linux/mutex.h>
> #include <linux/sysrq.h>
> +#include <linux/kfifo.h>
>
> #define SERIAL_TTY_MAJOR 188 /* Nice legal number now */
> #define SERIAL_TTY_MINORS 254 /* loads of devices :) */
> @@ -94,7 +95,7 @@ struct usb_serial_port {
> unsigned char *bulk_out_buffer;
> int bulk_out_size;
> struct urb *write_urb;
> - struct kfifo *write_fifo;
> + struct kfifo write_fifo;
> int write_urb_busy;
> __u8 bulk_out_endpointAddress;
>
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
>
>



\
 
 \ /
  Last update: 2009-12-23 17:49    [W:1.279 / U:0.140 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site