This is a note to let you know that I've just added the patch titled USB: ch341: fix use-after-free in TIOCMIWAIT to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >From fa1e11d5231c001c80a479160b5832933c5d35fb Mon Sep 17 00:00:00 2001 From: Johan Hovold <jhovold@xxxxxxxxx> Date: Tue, 19 Mar 2013 09:21:12 +0100 Subject: USB: ch341: fix use-after-free in TIOCMIWAIT Use the port wait queue and make sure to check the serial disconnected flag before accessing private port data after waking up. This is is needed as the private port data (including the wait queue itself) can be gone when waking up after a disconnect. Cc: stable <stable@xxxxxxxxxxxxxxx> Signed-off-by: Johan Hovold <jhovold@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/serial/ch341.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c index d255f66..07d4650 100644 --- a/drivers/usb/serial/ch341.c +++ b/drivers/usb/serial/ch341.c @@ -80,7 +80,6 @@ MODULE_DEVICE_TABLE(usb, id_table); struct ch341_private { spinlock_t lock; /* access lock */ - wait_queue_head_t delta_msr_wait; /* wait queue for modem status */ unsigned baud_rate; /* set baud rate */ u8 line_control; /* set line control value RTS/DTR */ u8 line_status; /* active status of modem control inputs */ @@ -252,7 +251,6 @@ static int ch341_port_probe(struct usb_serial_port *port) return -ENOMEM; spin_lock_init(&priv->lock); - init_waitqueue_head(&priv->delta_msr_wait); priv->baud_rate = DEFAULT_BAUD_RATE; priv->line_control = CH341_BIT_RTS | CH341_BIT_DTR; @@ -298,7 +296,7 @@ static void ch341_dtr_rts(struct usb_serial_port *port, int on) priv->line_control &= ~(CH341_BIT_RTS | CH341_BIT_DTR); spin_unlock_irqrestore(&priv->lock, flags); ch341_set_handshake(port->serial->dev, priv->line_control); - wake_up_interruptible(&priv->delta_msr_wait); + wake_up_interruptible(&port->delta_msr_wait); } static void ch341_close(struct usb_serial_port *port) @@ -491,7 +489,7 @@ static void ch341_read_int_callback(struct urb *urb) tty_kref_put(tty); } - wake_up_interruptible(&priv->delta_msr_wait); + wake_up_interruptible(&port->delta_msr_wait); } exit: @@ -517,11 +515,14 @@ static int wait_modem_info(struct usb_serial_port *port, unsigned int arg) spin_unlock_irqrestore(&priv->lock, flags); while (!multi_change) { - interruptible_sleep_on(&priv->delta_msr_wait); + interruptible_sleep_on(&port->delta_msr_wait); /* see if a signal did it */ if (signal_pending(current)) return -ERESTARTSYS; + if (port->serial->disconnected) + return -EIO; + spin_lock_irqsave(&priv->lock, flags); status = priv->line_status; multi_change = priv->multi_status_change; -- 1.8.0.rc0.18.gf84667d -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html