From a4720c650b68a5fe7faed2edeb0ad12645f7ae63 Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Fri, 9 Oct 2009 12:43:12 -0400 Subject: [PATCH] USB: serial: don't call release without attach This patch (as1295) fixes a recently-added bug in the USB serial core. If certain kinds of errors occur during probing, the core may call a serial driver's release method without previously calling the attach method. This causes some drivers (io_ti in particular) to perform an invalid memory access. The patch adds a new flag to keep track of whether or not attach has been called. Signed-off-by: Alan Stern Tested-by: Jean-Denis Girard CC: stable Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/usb-serial.c | 6 +++++- include/linux/usb/serial.h | 1 + 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c index aa6b2ae951ae..2d0f75d63ff0 100644 --- a/drivers/usb/serial/usb-serial.c +++ b/drivers/usb/serial/usb-serial.c @@ -156,7 +156,8 @@ static void destroy_serial(struct kref *kref) if (serial->minor != SERIAL_TTY_NO_MINOR) return_serial(serial); - serial->type->release(serial); + if (serial->attached) + serial->type->release(serial); /* Now that nothing is using the ports, they can be freed */ for (i = 0; i < serial->num_port_pointers; ++i) { @@ -1059,12 +1060,15 @@ int usb_serial_probe(struct usb_interface *interface, module_put(type->driver.owner); if (retval < 0) goto probe_error; + serial->attached = 1; if (retval > 0) { /* quietly accept this device, but don't bind to a serial port as it's about to disappear */ serial->num_ports = 0; goto exit; } + } else { + serial->attached = 1; } if (get_free_serial(serial, num_ports, &minor) == NULL) { diff --git a/include/linux/usb/serial.h b/include/linux/usb/serial.h index c17eb64d7213..ce911ebf91e8 100644 --- a/include/linux/usb/serial.h +++ b/include/linux/usb/serial.h @@ -150,6 +150,7 @@ struct usb_serial { struct usb_interface *interface; unsigned char disconnected:1; unsigned char suspending:1; + unsigned char attached:1; unsigned char minor; unsigned char num_ports; unsigned char num_port_pointers;