From 1026f710bd558147d50131cc9bbdd4844d3245e1 Mon Sep 17 00:00:00 2001 From: Marc Kleine-Budde Date: Fri, 10 Dec 2021 10:03:09 +0100 Subject: [PATCH] can: gs_usb: fix use of uninitialized variable, detach device on reception of invalid USB data commit 4a8737ff068724f509d583fef404d349adba80d6 upstream. The received data contains the channel the received data is associated with. If the channel number is bigger than the actual number of channels assume broken or malicious USB device and shut it down. This fixes the error found by clang: | drivers/net/can/usb/gs_usb.c:386:6: error: variable 'dev' is used | uninitialized whenever 'if' condition is true | if (hf->channel >= GS_MAX_INTF) | ^~~~~~~~~~~~~~~~~~~~~~~~~~ | drivers/net/can/usb/gs_usb.c:474:10: note: uninitialized use occurs here | hf, dev->gs_hf_size, gs_usb_receive_bulk_callback, | ^~~ Link: https://lore.kernel.org/all/20211210091158.408326-1-mkl@pengutronix.de Fixes: d08e973a77d1 ("can: gs_usb: Added support for the GS_USB CAN devices") Cc: stable@vger.kernel.org Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman --- drivers/net/can/usb/gs_usb.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/can/usb/gs_usb.c b/drivers/net/can/usb/gs_usb.c index 5e892be..9a30e5f 100644 --- a/drivers/net/can/usb/gs_usb.c +++ b/drivers/net/can/usb/gs_usb.c @@ -321,7 +321,7 @@ static void gs_usb_receive_bulk_callback(struct urb *urb) /* device reports out of range channel id */ if (hf->channel >= GS_MAX_INTF) - goto resubmit_urb; + goto device_detach; dev = usbcan->canch[hf->channel]; @@ -406,6 +406,7 @@ static void gs_usb_receive_bulk_callback(struct urb *urb) /* USB failure take down all interfaces */ if (rc == -ENODEV) { + device_detach: for (rc = 0; rc < GS_MAX_INTF; rc++) { if (usbcan->canch[rc]) netif_device_detach(usbcan->canch[rc]->netdev); -- 2.7.4