[openib-general] [PATCH repost] libmthca: stricter checks in mthca_create_srq

[Michael S. Tsirkin]

Roland, could you comment please?

---

If SRQ max_wr is too high, srq buf size calculation
srq->buf_size = srq->max << srq->wqe_shift
might overflow, resulting in crash on buffer access.

The simplest solution is to limit max_wr since practically hardware
does not support values bigger than 1 << 16.

Signed-off-by: Michael S. Tsirkin <mst at mellanox.co.il>

Index: openib/src/userspace/libmthca/src/verbs.c
===================================================================
--- openib/src/userspace/libmthca/src/verbs.c	(revision 8484)
+++ openib/src/userspace/libmthca/src/verbs.c	(working copy)
@@ -372,7 +372,7 @@ struct ibv_srq *mthca_create_srq(struct 
 	int                          ret;
 
 	/* Sanity check SRQ size before proceeding */
-	if (attr->attr.max_wr > 16 << 20 || attr->attr.max_sge > 64)
+	if (attr->attr.max_wr >= 1 << 16 || attr->attr.max_sge > 64)
 		return NULL;
 
 	srq = malloc(sizeof *srq);

-- 
MST