RDMA/uverbs: Verify MR access flags

commit ca95c141 upstream.

Verify that MR access flags that are passed from user are all supported
ones, otherwise an error is returned.

Fixes: 4fca0377 ("IB/uverbs: Move ib_access_flags and ib_read_counters_flags to uapi")
Link: https://lore.kernel.org/r/1578506740-22188-6-git-send-email-yishaih@mellanox.comSigned-off-by: Michael Guralnik <michaelgur@mellanox.com>
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

include/rdma/ib_verbs.h

@@ -3864,6 +3864,9 @@ static inline int ib_check_mr_access(int flags)
 	    !(flags & IB_ACCESS_LOCAL_WRITE))
 		return -EINVAL;
 
+	if (flags & ~IB_ACCESS_SUPPORTED)
+		return -EINVAL;
+
 	return 0;
 }