Hello All I tried to execute a program which creates 8152 process.( i=0; while( i<14) i++ fork(); ) with ulimit 8200. This program created 8152 processes and then stopped and came back to command prompt. this proves that my machine do have sufficient resources to create 8000 processes.
I found one more interesting thing on the same machine having FC6 distribution and Linux Kernel 2.6.18. i have set "ulimit -u 100". after setting this limit i tried to execute fork bombing program with guest account. after executing it expected result:- guest uesr should not able to fork another single process when it reaches to 100 processes count. actual result :- kernel allow me to create another processes without giving error. due to this i tried to execute same fork bombing program on another terminal with guest account and this fork bombing attack killed the box completely and machine needed reboot. will any please tell me why this is so? Regards Anand On 5/17/07, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
On Thu, 17 May 2007 20:15:32 +0530, Anand Jahagirdar said: > Hello All > I have set per user process limit ( ulimit) for both > root and guest account as 8000 by using option ulimit -u 8000.this is > Hard limit. still fork bombing attack killed the box and machine > needed reboot. will any body please tell me why this is so? i have > tried all this attack on machine with FC6 and Linux kernel 2.6.18. Convince me that your machine in fact has sufficient resources to spawn 8000 processes. Then retry it with "ulimit -u 100", and then do a binary search from 100 to 8000 to find out what value it stops working at.
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