[ Upstream commit 14d24e2cc77411301e906a8cf41884739de192de ] TCM buffer length doesn't necessarily equal 8 + ADDITIONAL LENGTH which might be considered an underflow in case of Data-In size being greater than 8 + ADDITIONAL LENGTH. So truncate buffer length to prevent underflow. Link: https://lore.kernel.org/r/20210209072202.41154-3-a.miloserdov@yadro.com Reviewed-by: Roman Bolshakov <r.bolshakov@yadro.com> Reviewed-by: Bodo Stroesser <bostroesser@gmail.com> Signed-off-by: Aleksandr Miloserdov <a.miloserdov@yadro.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>