datapath: Always return EFAULT to userspace when copy_to/from_user() fails.

copy_from_user() and copy_to_user() return the number of bytes that could
not be copied, not a conventional error code, so we need to translate it
into -EFAULT ourselves.

diff --git a/datapath/datapath.c b/datapath/datapath.c
index 851af969ecd70ed879380242e76a88496ea36ab1..e636c8ad0d79ba50f2c86776a76fd36cb979ee87 100644 (file)
--- a/datapath/datapath.c
+++ b/datapath/datapath.c
@@ -779,6 +779,7 @@ static int set_flow_actions(struct datapath *dp, struct odp_flow __user *ufp)
        error = -ENOMEM;
        if (!new_acts)
                goto error;
+       error = -EFAULT;
        if (copy_from_user(new_acts->actions, uf.actions,
                           uf.n_actions * sizeof *uf.actions))
                goto error_free_actions;
@@ -1133,7 +1134,7 @@ get_dp_stats(struct datapath *dp, struct odp_stats __user *statsp)
        }
        stats.max_miss_queue = DP_MAX_QUEUE_LEN;
        stats.max_action_queue = DP_MAX_QUEUE_LEN;
-       return copy_to_user(statsp, &stats, sizeof stats);
+       return copy_to_user(statsp, &stats, sizeof stats) ? -EFAULT : 0;
 }
 
 static int
@@ -1143,7 +1144,7 @@ put_port(const struct net_bridge_port *p, struct odp_port __user *uop)
        memset(&op, 0, sizeof op);
        strncpy(op.devname, p->dev->name, sizeof op.devname);
        op.port = p->port_no;
-       return copy_to_user(uop, &op, sizeof op);
+       return copy_to_user(uop, &op, sizeof op) ? -EFAULT : 0;
 }
 
 static int