[SCSI] erase invalid data returned by device
Alan Stern authored

This patch (as1108) fixes a problem that can occur with certain USB
mass-storage devices: They return invalid data together with a residue
indicating that the data should be ignored.  Rather than leave the
invalid data in a transfer buffer, where it can get misinterpreted,
the patch clears the invalid portion of the buffer.

This solves a problem (wrong write-protect setting detected) reported
by Maciej Rutecki and Peter Teoh.
Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Tested-by: default avatarPeter Teoh <htmldeveloper@gmail.com>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@HansenPartnership.com>
bdb2b8ca