[v2,1/2] ibacm: Incorrect usage of BE byte order of MLID attach/detach_mcast()

Commit Message

Michael J. Ruhl Oct. 16, 2017, 2:24 p.m. UTC

From: Michael J. Ruhl <[e-mail]>

The MLID value passed to ibv_attach/detach_mcast() must be in host
byte order.

acmp.c incorrectly uses the big endian format when doing a multicast
attach/detach (join). Multicast packets are used to do name resolution
by the libibacmp library.

There are two possible results because of this issue.

If a kernel has commit 8561eae60ff9, the attach will fail with an
EINVAL.  ibacm will log this as a failure during the multicast join.

If a kernel does not have commit 8561eae60ff9, the attach will
complete successfully.  Packets sent to this address will be dropped
because the packet dlid value and the multicast address information
given by the attach will not match.

Update MLID usage to use the correct byte order.

Reviewed-by: Mike Marciniszyn <[e-mail]>
Signed-off-by: Michael J. Ruhl <[e-mail]>
---
v1 -> v2
   * Update kernel commit reference to correct commit id.
---
 ibacm/prov/acmp/src/acmp.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)


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Patch

diff --git a/ibacm/prov/acmp/src/acmp.c b/ibacm/prov/acmp/src/acmp.c
index aa78416..78d9a29 100644
--- a/ibacm/prov/acmp/src/acmp.c
+++ b/ibacm/prov/acmp/src/acmp.c
@@ -732,7 +732,7 @@  static void acmp_process_join_resp(struct acm_sa_mad *sa_mad)
 			acm_log(0, "ERROR - unable to create ah\n");
 			goto out;
 		}
-		ret = ibv_attach_mcast(ep->qp, &mc_rec->mgid, mc_rec->mlid);
+		ret = ibv_attach_mcast(ep->qp, &dest->mgid, dest->av.dlid);
 		if (ret) {
 			acm_log(0, "ERROR - unable to attach QP to multicast group\n");
 			ibv_destroy_ah(dest->ah);
@@ -1429,7 +1429,7 @@  static void acmp_ep_join(struct acmp_ep *ep)
 
 	if (ep->mc_dest[0].state == ACMP_READY && ep->mc_dest[0].ah) {
 		ibv_detach_mcast(ep->qp, &ep->mc_dest[0].mgid,
-				 be16toh(ep->mc_dest[0].av.dlid));
+				 ep->mc_dest[0].av.dlid);
 		ibv_destroy_ah(ep->mc_dest[0].ah);
 		ep->mc_dest[0].ah = NULL;
 	}