[PATCH net 14/20] can: kvaser_usb_leaf: kvaser_usb_leaf_wait_cmd(): validate received command extents
From: Marc Kleine-Budde <mkl@pengutronix.de>
Date: 2026-07-29 10:29:32
Also in:
linux-can
Subsystem:
can network drivers, the rest · Maintainers:
Marc Kleine-Budde, Vincent Mailhol, Linus Torvalds
From: Pengpeng Hou <redacted>
The wait and bulk receive paths walk variable-length commands from a
USB buffer. A nonzero command shorter than CMD_HEADER_LEN can still be
dispatched, and the wait path copies a matching command into a fixed
caller-owned struct kvaser_cmd using the device-provided length.
Reject nonzero commands that do not contain the fixed header or that
extend beyond the current USB buffer item. In the wait path, also reject
a matching command that exceeds the destination before copying it.
Fixes: 080f40a6fa28 ("can: kvaser_usb: Add support for Kvaser CAN/USB devices")
Signed-off-by: Pengpeng Hou <redacted>
Link: https://patch.msgid.link/20260722042221.44066-1-pengpeng@iscas.ac.cn
Cc: stable@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c b/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c
index df737cfc5ea0..a876c7819b81 100644
--- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c
+++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c@@ -691,13 +691,22 @@ static int kvaser_usb_leaf_wait_cmd(const struct kvaser_usb *dev, u8 id, continue; } - if (pos + tmp->len > actual_len) { + if (tmp->len < CMD_HEADER_LEN || + tmp->len > actual_len - pos) { dev_err_ratelimited(&dev->intf->dev, "Format error\n"); break; } if (tmp->id == id) { + if (tmp->len > sizeof(*cmd)) { + dev_err_ratelimited(&dev->intf->dev, + "Received command %u too large (%u)\n", + tmp->id, tmp->len); + err = -EIO; + goto end; + } + memcpy(cmd, tmp, tmp->len); goto end; }
@@ -1737,7 +1746,7 @@ static void kvaser_usb_leaf_read_bulk_callback(struct kvaser_usb *dev, continue; } - if (pos + cmd->len > len) { + if (cmd->len < CMD_HEADER_LEN || cmd->len > len - pos) { dev_err_ratelimited(&dev->intf->dev, "Format error\n"); break; }
--
2.53.0