socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000040)={0xffffffffffffffff, 0xffffffffffffffff}) getsockopt$sock_buf(r0, 0x1, 0x1f, &(0x7f0000000080)=""/120, &(0x7f0000000000)=0x78)