Messages in this thread Patch in this message | | | From | Johan Hovold <> | Subject | [PATCH 7/9] USB: serial: fix missing locking on fifo in write callback | Date | Wed, 17 Mar 2010 23:00:43 +0100 |
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On errors the fifo was reset without any locking. This could race with write which do kfifo_put and perhaps also chars_in_buffer and write_room.
Every other access to the fifo is protected using the port lock so better add it to the error path as well.
Signed-off-by: Johan Hovold <jhovold@gmail.com> --- drivers/usb/serial/generic.c | 7 +++++-- 1 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c index 8d6d790..d3ef69f 100644 --- a/drivers/usb/serial/generic.c +++ b/drivers/usb/serial/generic.c @@ -518,10 +518,13 @@ void usb_serial_generic_write_bulk_callback(struct urb *urb) port->write_urb_busy = 0; spin_unlock_irqrestore(&port->lock, flags); - if (status) + if (status) { + spin_lock_irqsave(&port->lock, flags); kfifo_reset_out(&port->write_fifo); - else + spin_unlock_irqrestore(&port->lock, flags); + } else { usb_serial_generic_write_start(port); + } } if (status) -- 1.7.0.2
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