From: Pengpeng Hou Date: Wed, 22 Jul 2026 04:22:21 +0000 (+0800) Subject: can: kvaser_usb_leaf: kvaser_usb_leaf_wait_cmd(): validate received command extents X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0293dd153f9dbc1ddf5dacdccc76b363bce4a8ee;p=thirdparty%2Fkernel%2Fstable.git can: kvaser_usb_leaf: kvaser_usb_leaf_wait_cmd(): validate received command extents 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 Link: https://patch.msgid.link/20260722042221.44066-1-pengpeng@iscas.ac.cn Cc: stable@kernel.org Signed-off-by: Marc Kleine-Budde --- 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; }