From: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> 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@xxxxxxxxxxxxxx Fixes: d08e973a77d1 ("can: gs_usb: Added support for the GS_USB CAN devices") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/can/usb/gs_usb.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/net/can/usb/gs_usb.c +++ b/drivers/net/can/usb/gs_usb.c @@ -328,7 +328,7 @@ static void gs_usb_receive_bulk_callback /* device reports out of range channel id */ if (hf->channel >= GS_MAX_INTF) - goto resubmit_urb; + goto device_detach; dev = usbcan->canch[hf->channel]; @@ -413,6 +413,7 @@ static void gs_usb_receive_bulk_callback /* 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);
