uas: improve error handling

(1) Handle data pipe errors: When the data urb failed we
    didn't transfer anything, update scsi_cmnd accordingly.
(2) Cancel data transfers when we got back an error on the
    status pipe.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 13 insertions, 1 deletions

diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c
index b589b2e0e928..d8b7bc6ea141 100644
--- a/drivers/usb/storage/uas.c
+++ b/drivers/usb/storage/uas.c
@@ -242,6 +242,13 @@ static void uas_stat_cmplt(struct urb *urb)
                         uas_sense_old(urb, cmnd);
                 else
                         uas_sense(urb, cmnd);
+                if (cmnd->result != 0) {
+                        /* cancel data transfers on error */
+                        if (cmdinfo->state & DATA_IN_URB_INFLIGHT)
+                                usb_unlink_urb(cmdinfo->data_in_urb);
+                        if (cmdinfo->state & DATA_OUT_URB_INFLIGHT)
+                                usb_unlink_urb(cmdinfo->data_out_urb);
+                }
                 cmdinfo->state &= ~COMMAND_INFLIGHT;
                 uas_try_complete(cmnd, __func__);
                 break;
@@ -272,7 +279,12 @@ static void uas_data_cmplt(struct urb *urb)
                 cmdinfo->state &= ~DATA_OUT_URB_INFLIGHT;
         }
         BUG_ON(sdb == NULL);
-        sdb->resid = sdb->length - urb->actual_length;
+        if (urb->status) {
+                /* error: no data transfered */
+                sdb->resid = sdb->length;
+        } else {
+                sdb->resid = sdb->length - urb->actual_length;
+        }
         uas_try_complete(cmnd, __func__);
 }