r0 = socket$inet(0x2, 0xa, 0x0)
r1 = openat$procfs(0xffffffffffffff9c, &(0x7f0000000040)='/proc/cgroups\x00', 0x0, 0x0)
sendfile(r0, r1, &(0x7f0000000080)=0x4, 0x7)