IB/qib: Prevent context loss

If a context has already been assigned to an FD, prevent
another assignment.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

diff --git a/drivers/infiniband/hw/qib/qib_file_ops.c b/drivers/infiniband/hw/qib/qib_file_ops.c
index ff946d5f59e4071606ebc00fff43df5a56dde2f6..382466a90da7331e4492fab59d60bf904db36df1 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_file_ops.c
+++ b/drivers/infiniband/hw/qib/qib_file_ops.c
@@ -2178,6 +2178,11 @@ static ssize_t qib_write(struct file *fp, const char __user *data,
 
        switch (cmd.type) {
        case QIB_CMD_ASSIGN_CTXT:
+               if (rcd) {
+                       ret = -EINVAL;
+                       goto bail;
+               }
+
                ret = qib_assign_ctxt(fp, &cmd.cmd.user_info);
                if (ret)
                        goto bail;