From c804743181ad14578d8ea5b2e7b8bd7a2efe64ae Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Wed, 27 Aug 2014 11:55:19 +0200 Subject: [PATCH] USB: serial: fix potential heap buffer overflow commit 5654699fb38512bdbfc0f892ce54fce75bdc2bab upstream. Make sure to verify the number of ports requested by subdriver to avoid writing beyond the end of fixed-size array in interface data. The current usb-serial implementation is limited to eight ports per interface but failed to verify that the number of ports requested by a subdriver (which could have been determined from device descriptors) did not exceed this limit. Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman [lizf: Backported to 3.4: s/ddev/\&interface->dev/] Signed-off-by: Zefan Li --- drivers/usb/serial/usb-serial.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c index 815d86d..a08230e 100644 --- a/drivers/usb/serial/usb-serial.c +++ b/drivers/usb/serial/usb-serial.c @@ -889,6 +889,11 @@ int usb_serial_probe(struct usb_interface *interface, num_ports = type->num_ports; } + if (num_ports > MAX_NUM_PORTS) { + dev_warn(&interface->dev, "too many ports requested: %d\n", num_ports); + num_ports = MAX_NUM_PORTS; + } + serial->num_ports = num_ports; serial->num_bulk_in = num_bulk_in; serial->num_bulk_out = num_bulk_out; -- 2.7.4