[PATCH AUTOSEL for 4.4 047/167] USB: ene_usb6250: fix SCSI residue overwriting

From: Sasha Levin
Date: Mon Mar 19 2018 - 12:08:47 EST


From: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>

[ Upstream commit aa18c4b6e0e39bfb00af48734ec24bc189ac9909 ]

In the ene_usb6250 sub-driver for usb-storage, the SCSI residue is not
reported correctly. The residue is initialized to 0, but this value
is overwritten whenever the driver sends firmware to the card reader
before performing the current command. As a result, a valid READ or
WRITE operation appears to have failed, causing the SCSI core to retry
the command multiple times and eventually fail.

This patch fixes the problem by resetting the SCSI residue to 0 after
sending firmware to the device.

Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Reported-and-tested-by: Andreas Hartmann <andihartmann@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
drivers/usb/storage/ene_ub6250.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/usb/storage/ene_ub6250.c b/drivers/usb/storage/ene_ub6250.c
index eebfa09bccc1..962bb6376b0c 100644
--- a/drivers/usb/storage/ene_ub6250.c
+++ b/drivers/usb/storage/ene_ub6250.c
@@ -1953,6 +1953,8 @@ static int ene_load_bincode(struct us_data *us, unsigned char flag)
bcb->CDB[0] = 0xEF;

result = ene_send_scsi_cmd(us, FDIR_WRITE, buf, 0);
+ if (us->srb != NULL)
+ scsi_set_resid(us->srb, 0);
info->BIN_FLAG = flag;
kfree(buf);

--
2.14.1