Linux-2.6.11 can't disable CAD

From: Richard B. Johnson
Date: Thu Apr 07 2005 - 10:18:11 EST



In the not-too distant past, one could disable Ctl-Alt-DEL.
Can't do it anymore.

Script started on Thu 07 Apr 2005 10:58:11 AM EDT
[SNIPPED leading stuff...]

mprotect(0xb7fe4000, 28672, PROT_READ|PROT_EXEC) = 0
brk(0) = 0x804a000
brk(0x8053000) = 0x8053000
reboot(LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, LINUX_REBOOT_CMD_CAD_OFF) = 0
pause( <unfinished ...>
_exit(0) = ?
# exit
Script done on Thu 07 Apr 2005 10:58:21 AM EDT

Observe that reboot() returns 0 and `strace` understands what
parameters were passed. The result is that, if I hit Ctl-Alt-Del,
`init` will still execute the shutdown-order (INIT 0).

A side note, while researching this problem, I think I found
that LINUX_REBOOT_MAGIC2 is Linus' birthday (in hex). Maybe
the problem is that he no longer observes his birthday?

Cheers,
Dick Johnson
Penguin : Linux version 2.6.11 on an i686 machine (5537.79 BogoMips).
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