r0 = openat$procfs(0xffffffffffffff9c, &(0x7f0000000300)='/proc/key-users\x00', 0x0, 0x0)
r1 = openat$tcp_mem(0xffffffffffffff9c, &(0x7f0000000080)='/proc/sys/net/ipv4/tcp_wmem\x00', 0x1, 0x0)
sendfile(r1, r0, &(0x7f0000000040)=0xb, 0x80000001)