The patch titled usb-serial: ftdi_sio: fix reference counting of ftdi_private has been removed from the -mm tree. Its filename was usb-serial-ftdi_sio-fix-reference-counting-of-ftdi_private.patch This patch was dropped because it was merged into mainline or a subsystem tree The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: usb-serial: ftdi_sio: fix reference counting of ftdi_private From: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> This patch (as1238) adds proper reference counting for ftdi_sio's private data structure. Without it, the driver will free the structure while it is still in use if the user unplugs the serial device before closing the device file. The patch also replaces a slightly dangerous cancel_delayed_work/flush_scheduled_work pair with cancel_delayed_work_sync, which is always safer. Reported-by: Daniel Mack <daniel@xxxxxxxx> Tested-by: Daniel Mack <daniel@xxxxxxxx> Cc: Greg KH <greg@xxxxxxxxx> Cc: <stable@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/usb/serial/ftdi_sio.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff -puN drivers/usb/serial/ftdi_sio.c~usb-serial-ftdi_sio-fix-reference-counting-of-ftdi_private drivers/usb/serial/ftdi_sio.c --- a/drivers/usb/serial/ftdi_sio.c~usb-serial-ftdi_sio-fix-reference-counting-of-ftdi_private +++ a/drivers/usb/serial/ftdi_sio.c @@ -56,6 +56,7 @@ static __u16 vendor = FTDI_VID; static __u16 product; struct ftdi_private { + struct kref kref; ftdi_chip_type_t chip_type; /* type of device, either SIO or FT8U232AM */ int baud_base; /* baud base clock for divisor setting */ @@ -1423,6 +1424,7 @@ static int ftdi_sio_port_probe(struct us return -ENOMEM; } + kref_init(&priv->kref); spin_lock_init(&priv->rx_lock); spin_lock_init(&priv->tx_lock); init_waitqueue_head(&priv->delta_msr_wait); @@ -1539,6 +1541,13 @@ static void ftdi_shutdown(struct usb_ser dbg("%s", __func__); } +static void ftdi_sio_priv_release(struct kref *k) +{ + struct ftdi_private *priv = container_of(k, struct ftdi_private, kref); + + kfree(priv); +} + static int ftdi_sio_port_remove(struct usb_serial_port *port) { struct ftdi_private *priv = usb_get_serial_port_data(port); @@ -1553,7 +1562,7 @@ static int ftdi_sio_port_remove(struct u if (priv) { usb_set_serial_port_data(port, NULL); - kfree(priv); + kref_put(&priv->kref, ftdi_sio_priv_release); } return 0; @@ -1618,7 +1627,8 @@ static int ftdi_open(struct tty_struct * dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __func__, result); - + else + kref_get(&priv->kref); return result; } /* ftdi_open */ @@ -1665,11 +1675,11 @@ static void ftdi_close(struct usb_serial /* cancel any scheduled reading */ - cancel_delayed_work(&priv->rx_work); - flush_scheduled_work(); + cancel_delayed_work_sync(&priv->rx_work); /* shutdown our bulk read */ usb_kill_urb(port->read_urb); + kref_put(&priv->kref, ftdi_sio_priv_release); } /* ftdi_close */ _ Patches currently in -mm which might be from stern@xxxxxxxxxxxxxxxxxxx are linux-next.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html