r0 = openat$procfs(0xffffffffffffff9c, &(0x7f00000000c0)='/proc/key-users\x00', 0x0, 0x0)
preadv(r0, &(0x7f0000000440)=[{&(0x7f0000000200)=""/177, 0xb1}], 0x1, 0x40, 0x0)