diff options
| author | Stephane Grosjean <s.grosjean@peak-system.com> | 2018-01-15 16:31:19 +0100 |
|---|---|---|
| committer | Marc Kleine-Budde <mkl@pengutronix.de> | 2018-01-16 15:33:15 +0100 |
| commit | d8a243af1a68395e07ac85384a2740d4134c67f4 (patch) | |
| tree | d454f1388e00653301eb510d1dbef485a48f6df0 | |
| parent | 6311b7ce42e0c1d6d944bc099dc47e936c20cf11 (diff) | |
can: peak: fix potential bug in packet fragmentation
In some rare conditions when running one PEAK USB-FD interface over
a non high-speed USB controller, one useless USB fragment might be sent.
This patch fixes the way a USB command is fragmented when its length is
greater than 64 bytes and when the underlying USB controller is not a
high-speed one.
Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
| -rw-r--r-- | drivers/net/can/usb/peak_usb/pcan_usb_fd.c | 21 |
1 files changed, 11 insertions, 10 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 7ccdc3e30c98..53d6bb045e9e 100644 --- a/drivers/net/can/usb/peak_usb/pcan_usb_fd.c +++ b/drivers/net/can/usb/peak_usb/pcan_usb_fd.c @@ -184,7 +184,7 @@ static int pcan_usb_fd_send_cmd(struct peak_usb_device *dev, void *cmd_tail) void *cmd_head = pcan_usb_fd_cmd_buffer(dev); int err = 0; u8 *packet_ptr; - int i, n = 1, packet_len; + int packet_len; ptrdiff_t cmd_len; /* usb device unregistered? */ @@ -201,17 +201,13 @@ static int pcan_usb_fd_send_cmd(struct peak_usb_device *dev, void *cmd_tail) } packet_ptr = cmd_head; + packet_len = cmd_len; /* firmware is not able to re-assemble 512 bytes buffer in full-speed */ - if ((dev->udev->speed != USB_SPEED_HIGH) && - (cmd_len > PCAN_UFD_LOSPD_PKT_SIZE)) { - packet_len = PCAN_UFD_LOSPD_PKT_SIZE; - n += cmd_len / packet_len; - } else { - packet_len = cmd_len; - } + if (unlikely(dev->udev->speed != USB_SPEED_HIGH)) + packet_len = min(packet_len, PCAN_UFD_LOSPD_PKT_SIZE); - for (i = 0; i < n; i++) { + do { err = usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, PCAN_USBPRO_EP_CMDOUT), @@ -224,7 +220,12 @@ static int pcan_usb_fd_send_cmd(struct peak_usb_device *dev, void *cmd_tail) } packet_ptr += packet_len; - } + cmd_len -= packet_len; + + if (cmd_len < PCAN_UFD_LOSPD_PKT_SIZE) + packet_len = cmd_len; + + } while (packet_len > 0); return err; } |