From 4a8737ff068724f509d583fef404d349adba80d6 Mon Sep 17 00:00:00 2001 From: Marc Kleine-Budde Date: Fri, 10 Dec 2021 10:03:09 +0100 Subject: [PATCH 1/2] can: gs_usb: fix use of uninitialized variable, detach device on reception of invalid USB data 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 --- 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 1b400de00f517..d7ce2c5956f4c 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); From 5f33a09e769a9da0482f20a6770a342842443776 Mon Sep 17 00:00:00 2001 From: Marc Kleine-Budde Date: Wed, 5 Jan 2022 14:01:12 +0100 Subject: [PATCH 2/2] can: isotp: convert struct tpcon::{idx,len} to unsigned int In isotp_rcv_ff() 32 bit of data received over the network is assigned to struct tpcon::len. Later in that function the length is checked for the maximal supported length against MAX_MSG_LENGTH. As struct tpcon::len is an "int" this check does not work, if the provided length overflows the "int". Later on struct tpcon::idx is compared against struct tpcon::len. To fix this problem this patch converts both struct tpcon::{idx,len} to unsigned int. Fixes: e057dd3fc20f ("can: add ISO 15765-2:2016 transport protocol") Link: https://lore.kernel.org/all/20220105132429.1170627-1-mkl@pengutronix.de Cc: stable@vger.kernel.org Acked-by: Oliver Hartkopp Reported-by: syzbot+4c63f36709a642f801c5@syzkaller.appspotmail.com Signed-off-by: Marc Kleine-Budde --- net/can/isotp.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/can/isotp.c b/net/can/isotp.c index df6968b28bf41..02cbcb2ecf0db 100644 --- a/net/can/isotp.c +++ b/net/can/isotp.c @@ -119,8 +119,8 @@ enum { }; struct tpcon { - int idx; - int len; + unsigned int idx; + unsigned int len; u32 state; u8 bs; u8 sn;