commit 1c636f801615bdfc9b1d46904e8258c7a025670b
author Eli Cohen <eli@dev.mellanox.co.il> Thu Oct 31 15:26:32 2013 +0200
committer Roland Dreier <roland@purestorage.com> Fri Nov 15 10:25:32 2013 -0800
tree 600ff4b245e9287489c6c4b8a3a132f5adae5eb9
parent 180771a3707a4c0577cbf4f830c754dbabfdfccb

IB/core: Encorce MR access rights rules on kernel consumers

Enforce the rule that when requesting remote write or atomic permissions, local
write must be indicated as well. See IB spec 11.2.8.2.

Spotted by: Hagay Abramovsky <hagaya@mellanox.com>
Signed-off-by: Eli Cohen <eli@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

drivers/infiniband/core/uverbs_cmd.c

diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index 5bb2a82d..7f671b7 100644
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -939,13 +939,9 @@
 	if ((cmd.start & ~PAGE_MASK) != (cmd.hca_va & ~PAGE_MASK))
 		return -EINVAL;
 
-	/*
-	 * Local write permission is required if remote write or
-	 * remote atomic permission is also requested.
-	 */
-	if (cmd.access_flags & (IB_ACCESS_REMOTE_ATOMIC | IB_ACCESS_REMOTE_WRITE) &&
-	    !(cmd.access_flags & IB_ACCESS_LOCAL_WRITE))
-		return -EINVAL;
+	ret = ib_check_mr_access(cmd.access_flags);
+	if (ret)
+		return ret;
 
 	uobj = kmalloc(sizeof *uobj, GFP_KERNEL);
 	if (!uobj)

drivers/infiniband/core/verbs.c

diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
index 84f5027..d4f6ddf 100644
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -961,6 +961,11 @@
 struct ib_mr *ib_get_dma_mr(struct ib_pd *pd, int mr_access_flags)
 {
 	struct ib_mr *mr;
+	int err;
+
+	err = ib_check_mr_access(mr_access_flags);
+	if (err)
+		return ERR_PTR(err);
 
 	mr = pd->device->get_dma_mr(pd, mr_access_flags);
 
@@ -983,6 +988,11 @@
 			     u64 *iova_start)
 {
 	struct ib_mr *mr;
+	int err;
+
+	err = ib_check_mr_access(mr_access_flags);
+	if (err)
+		return ERR_PTR(err);
 
 	if (!pd->device->reg_phys_mr)
 		return ERR_PTR(-ENOSYS);
@@ -1013,6 +1023,10 @@
 	struct ib_pd *old_pd;
 	int ret;
 
+	ret = ib_check_mr_access(mr_access_flags);
+	if (ret)
+		return ret;
+
 	if (!mr->device->rereg_phys_mr)
 		return -ENOSYS;
 

include/rdma/ib_verbs.h

diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 60354d5..68c053d 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -2386,4 +2386,17 @@
 			       struct ib_flow_attr *flow_attr, int domain);
 int ib_destroy_flow(struct ib_flow *flow_id);
 
+static inline int ib_check_mr_access(int flags)
+{
+	/*
+	 * Local write permission is required if remote write or
+	 * remote atomic permission is also requested.
+	 */
+	if (flags & (IB_ACCESS_REMOTE_ATOMIC | IB_ACCESS_REMOTE_WRITE) &&
+	    !(flags & IB_ACCESS_LOCAL_WRITE))
+		return -EINVAL;
+
+	return 0;
+}
+
 #endif /* IB_VERBS_H */