[PATCH 3.16 091/134] IB/core: For multicast functions, verify that LIDs are multicast LIDs

[Ben Hutchings]

3.16.47-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: "Michael J. Ruhl" <michael.j.ruhl@xxxxxxxxx>

commit 8561eae60ff9417a50fa1fb2b83ae950dc5c1e21 upstream.

The Infiniband spec defines "A multicast address is defined by a
MGID and a MLID" (section 10.5).  Currently the MLID value is not
validated.

Add check to verify that the MLID value is in the correct address
range.

Fixes: 0c33aeedb2cf ("[IB] Add checks to multicast attach and detach")
Reviewed-by: Ira Weiny <ira.weiny@xxxxxxxxx>
Reviewed-by: Dasaratharaman Chandramouli <dasaratharaman.chandramouli@xxxxxxxxx>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@xxxxxxxxx>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxx>
Reviewed-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx>
[bwh: Backported to 3.16: use literal number instead of IB_MULTICAST_LID_BASE]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/infiniband/core/verbs.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -1346,7 +1346,9 @@ int ib_attach_mcast(struct ib_qp *qp, un
 
 	if (!qp->device->attach_mcast)
 		return -ENOSYS;
-	if (gid->raw[0] != 0xff || qp->qp_type != IB_QPT_UD)
+	if (gid->raw[0] != 0xff || qp->qp_type != IB_QPT_UD ||
+	    lid < 0xC000 ||
+	    lid == be16_to_cpu(IB_LID_PERMISSIVE))
 		return -EINVAL;
 
 	ret = qp->device->attach_mcast(qp, gid, lid);
@@ -1362,7 +1364,9 @@ int ib_detach_mcast(struct ib_qp *qp, un
 
 	if (!qp->device->detach_mcast)
 		return -ENOSYS;
-	if (gid->raw[0] != 0xff || qp->qp_type != IB_QPT_UD)
+	if (gid->raw[0] != 0xff || qp->qp_type != IB_QPT_UD ||
+	    lid < 0xC000 ||
+	    lid == be16_to_cpu(IB_LID_PERMISSIVE))
 		return -EINVAL;
 
 	ret = qp->device->detach_mcast(qp, gid, lid);