diff options
author | Dan Carpenter <dan.carpenter@oracle.com> | 2020-08-13 17:06:04 +0300 |
---|---|---|
committer | Marc Kleine-Budde <mkl@pengutronix.de> | 2020-11-03 22:30:32 +0100 |
commit | a6921dd524fe31d1f460c161d3526a407533b6db (patch) | |
tree | 26020c437850d8682866b576e4aadb0cbd35d242 /drivers | |
parent | 79c43333bdd5a7026a5aab606b53053b643585e7 (diff) |
can: peak_usb: add range checking in decode operations
These values come from skb->data so Smatch considers them untrusted. I
believe Smatch is correct but I don't have a way to test this.
The usb_if->dev[] array has 2 elements but the index is in the 0-15
range without checks. The cfd->len can be up to 255 but the maximum
valid size is CANFD_MAX_DLEN (64) so that could lead to memory
corruption.
Fixes: 0a25e1f4f185 ("can: peak_usb: add support for PEAK new CANFD USB adapters")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20200813140604.GA456946@mwanda
Acked-by: Stephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/net/can/usb/peak_usb/pcan_usb_fd.c | 48 |
1 files changed, 37 insertions, 11 deletions
diff --git a/drivers/net/can/usb/peak_usb/pcan_usb_fd.c b/drivers/net/can/usb/peak_usb/pcan_usb_fd.c index ab63fd9eb982..d29d20525588 100644 --- a/drivers/net/can/usb/peak_usb/pcan_usb_fd.c +++ b/drivers/net/can/usb/peak_usb/pcan_usb_fd.c @@ -468,12 +468,18 @@ static int pcan_usb_fd_decode_canmsg(struct pcan_usb_fd_if *usb_if, struct pucan_msg *rx_msg) { struct pucan_rx_msg *rm = (struct pucan_rx_msg *)rx_msg; - struct peak_usb_device *dev = usb_if->dev[pucan_msg_get_channel(rm)]; - struct net_device *netdev = dev->netdev; + struct peak_usb_device *dev; + struct net_device *netdev; struct canfd_frame *cfd; struct sk_buff *skb; const u16 rx_msg_flags = le16_to_cpu(rm->flags); + if (pucan_msg_get_channel(rm) >= ARRAY_SIZE(usb_if->dev)) + return -ENOMEM; + + dev = usb_if->dev[pucan_msg_get_channel(rm)]; + netdev = dev->netdev; + if (rx_msg_flags & PUCAN_MSG_EXT_DATA_LEN) { /* CANFD frame case */ skb = alloc_canfd_skb(netdev, &cfd); @@ -519,15 +525,21 @@ static int pcan_usb_fd_decode_status(struct pcan_usb_fd_if *usb_if, struct pucan_msg *rx_msg) { struct pucan_status_msg *sm = (struct pucan_status_msg *)rx_msg; - struct peak_usb_device *dev = usb_if->dev[pucan_stmsg_get_channel(sm)]; - struct pcan_usb_fd_device *pdev = - container_of(dev, struct pcan_usb_fd_device, dev); + struct pcan_usb_fd_device *pdev; enum can_state new_state = CAN_STATE_ERROR_ACTIVE; enum can_state rx_state, tx_state; - struct net_device *netdev = dev->netdev; + struct peak_usb_device *dev; + struct net_device *netdev; struct can_frame *cf; struct sk_buff *skb; + if (pucan_stmsg_get_channel(sm) >= ARRAY_SIZE(usb_if->dev)) + return -ENOMEM; + + dev = usb_if->dev[pucan_stmsg_get_channel(sm)]; + pdev = container_of(dev, struct pcan_usb_fd_device, dev); + netdev = dev->netdev; + /* nothing should be sent while in BUS_OFF state */ if (dev->can.state == CAN_STATE_BUS_OFF) return 0; @@ -579,9 +591,14 @@ static int pcan_usb_fd_decode_error(struct pcan_usb_fd_if *usb_if, struct pucan_msg *rx_msg) { struct pucan_error_msg *er = (struct pucan_error_msg *)rx_msg; - struct peak_usb_device *dev = usb_if->dev[pucan_ermsg_get_channel(er)]; - struct pcan_usb_fd_device *pdev = - container_of(dev, struct pcan_usb_fd_device, dev); + struct pcan_usb_fd_device *pdev; + struct peak_usb_device *dev; + + if (pucan_ermsg_get_channel(er) >= ARRAY_SIZE(usb_if->dev)) + return -EINVAL; + + dev = usb_if->dev[pucan_ermsg_get_channel(er)]; + pdev = container_of(dev, struct pcan_usb_fd_device, dev); /* keep a trace of tx and rx error counters for later use */ pdev->bec.txerr = er->tx_err_cnt; @@ -595,11 +612,17 @@ static int pcan_usb_fd_decode_overrun(struct pcan_usb_fd_if *usb_if, struct pucan_msg *rx_msg) { struct pcan_ufd_ovr_msg *ov = (struct pcan_ufd_ovr_msg *)rx_msg; - struct peak_usb_device *dev = usb_if->dev[pufd_omsg_get_channel(ov)]; - struct net_device *netdev = dev->netdev; + struct peak_usb_device *dev; + struct net_device *netdev; struct can_frame *cf; struct sk_buff *skb; + if (pufd_omsg_get_channel(ov) >= ARRAY_SIZE(usb_if->dev)) + return -EINVAL; + + dev = usb_if->dev[pufd_omsg_get_channel(ov)]; + netdev = dev->netdev; + /* allocate an skb to store the error frame */ skb = alloc_can_err_skb(netdev, &cf); if (!skb) @@ -716,6 +739,9 @@ static int pcan_usb_fd_encode_msg(struct peak_usb_device *dev, u16 tx_msg_size, tx_msg_flags; u8 can_dlc; + if (cfd->len > CANFD_MAX_DLEN) + return -EINVAL; + tx_msg_size = ALIGN(sizeof(struct pucan_tx_msg) + cfd->len, 4); tx_msg->size = cpu_to_le16(tx_msg_size); tx_msg->type = cpu_to_le16(PUCAN_MSG_CAN_TX); |