r0 = openat$procfs(0xffffffffffffff9c, &(0x7f0000000200)='/proc/key-users\x00', 0x0, 0x0)
preadv(r0, &(0x7f0000000240)=[{&(0x7f0000000280)=""/58, 0x3a}], 0x1, 0xc04, 0x0)