Re^2: EUID cannot be set

Mmm, I did in fact check that:

linux: demotion to sys(4294967294) failed: Bad file descriptor (euid: 
+-2)
aix: demotion to nobody(4294967294) failed:  (euid: -2)
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Niel

Comment on Re^2: EUID cannot be set Download Code

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Re^3: EUID cannot be set by mr_mischief (Monsignor) on May 10, 2007 at 20:19 UTC
Note on AIX's nobody user for Exim Services for Unix blog It seems this is not overflow. It's just a representation in one place using an unsigned value and in another using a signed value. Considering there are 4,294,967,296 values in a 32-bit integer and that the signed number would be in two's complement if negative, -2 is exactly the same as 4294967294. As a matter of fact, I believe your EUID is being set. It's just not being set to the right interpretation of the number. I suggest you ponder this code: `#!/usr/bin/perl -- use strict; use warnings; my $nobody = 4294967294; print $nobody . "\n"; $nobody = pack 'I', -2; $nobody = unpack 'I', $nobody; print $nobody . "\n";` [download] Christopher E. Stith	[reply] [d/l]

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Re^3: EUID cannot be set
by mr_mischief (Monsignor) on May 10, 2007 at 20:19 UTC

Note on AIX's nobody user for Exim

Services for Unix blog

#!/usr/bin/perl --
use strict;
use warnings;

my $nobody = 4294967294;
print $nobody . "\n";

$nobody = pack 'I', -2;
$nobody = unpack 'I', $nobody;
print $nobody . "\n";
[download]

Christopher E. Stith

[reply]
[d/l]