3.16.83-rc1 review patch. If anyone has any objections, please let me know.
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From: Suwan Kim suwan.kim027@gmail.com
commit aabb5b833872524eaf28f52187e5987984982264 upstream.
If a transaction error happens in vhci_recv_ret_submit(), event handler closes connection and changes port status to kick hub_event. Then hub tries to flush the endpoint URBs, but that causes infinite loop between usb_hub_flush_endpoint() and vhci_urb_dequeue() because "vhci_priv" in vhci_urb_dequeue() was already released by vhci_recv_ret_submit() before a transmission error occurred. Thus, vhci_urb_dequeue() terminates early and usb_hub_flush_endpoint() continuously calls vhci_urb_dequeue().
The root cause of this issue is that vhci_recv_ret_submit() terminates early without giving back URB when transaction error occurs in vhci_recv_ret_submit(). That causes the error URB to still be linked at endpoint list without “vhci_priv".
So, in the case of transaction error in vhci_recv_ret_submit(), unlink URB from the endpoint, insert proper error code in urb->status and give back URB.
Reported-by: Marek Marczykowski-Górecki marmarek@invisiblethingslab.com Tested-by: Marek Marczykowski-Górecki marmarek@invisiblethingslab.com Signed-off-by: Suwan Kim suwan.kim027@gmail.com Acked-by: Shuah Khan skhan@linuxfoundation.org Link: https://lore.kernel.org/r/20191213023055.19933-3-suwan.kim027@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org [bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings ben@decadent.org.uk --- drivers/staging/usbip/vhci_rx.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)
--- a/drivers/staging/usbip/vhci_rx.c +++ b/drivers/staging/usbip/vhci_rx.c @@ -88,16 +88,21 @@ static void vhci_recv_ret_submit(struct usbip_pack_pdu(pdu, urb, USBIP_RET_SUBMIT, 0);
/* recv transfer buffer */ - if (usbip_recv_xbuff(ud, urb) < 0) - return; + if (usbip_recv_xbuff(ud, urb) < 0) { + urb->status = -EPROTO; + goto error; + }
/* recv iso_packet_descriptor */ - if (usbip_recv_iso(ud, urb) < 0) - return; + if (usbip_recv_iso(ud, urb) < 0) { + urb->status = -EPROTO; + goto error; + }
/* restore the padding in iso packets */ usbip_pad_iso(ud, urb);
+error: if (usbip_dbg_flag_vhci_rx) usbip_dump_urb(urb);