From 9e818917657b4fd3b05c9654de90f007496b598e Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Tue, 3 Jan 2017 16:39:55 +0100 Subject: [PATCH] USB: serial: mos7840: fix NULL-deref at open commit 5c75633ef751dd4cd8f443dc35152c1ae563162e upstream. Fix NULL-pointer dereference in open() should the device lack the expected endpoints: Unable to handle kernel NULL pointer dereference at virtual address 00000030 ... PC is at mos7840_open+0x88/0x8dc [mos7840] Note that we continue to treat the interrupt-in endpoint as optional for now. Fixes: 3f5429746d91 ("USB: Moschip 7840 USB-Serial Driver") Signed-off-by: Johan Hovold [bwh: Backported to 3.2: add this check to the existing usb_serial_driver::attach implementation] Signed-off-by: Ben Hutchings --- drivers/usb/serial/mos7840.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c index 59fdb84d016f..6469d30739de 100644 --- a/drivers/usb/serial/mos7840.c +++ b/drivers/usb/serial/mos7840.c @@ -2386,6 +2386,12 @@ static int mos7840_startup(struct usb_serial *serial) return -1; } + if (serial->num_bulk_in < serial->num_ports || + serial->num_bulk_out < serial->num_ports) { + dev_err(&serial->interface->dev, "missing endpoints\n"); + return -ENODEV; + } + dev = serial->dev; dbg("%s", "Entering..."); -- 2.39.2