On Wed, Aug 19, 2015 at 06:37:32PM +0200, Christoph Hellwig wrote:

We have many WR opcodes that are only supported in kernel space
and/or require optional information to be copied into the WR
structure.  Reject all those not explicitly handled so that we
can't pass invalid information to drivers.

Cc: stable@vger.kernel.org
Signed-off-by: Christoph Hellwig <hch@lst.de>
 drivers/infiniband/core/uverbs_cmd.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

Oh yes, this is absolutely needed for -stable.

Reviewed-by: Jason Gunthorpe <redacted>

AFAIK, this path is rarely (never?) actually used. I think all the
drivers we have can post directly from userspace.

Jason