how to block everything from an entire /24

["Sibuyas" <sibuyas@i-mailbox.net>]

hi!

ive been getting funny looking entries from my log file, and everytime this
happens, load average on our server would go as high up as 20++, then mysql,
among other processes, would die.  here're a few lines from the serverlog:

Apr  8 22:38:53 ickis kernel: Packet log: input DENY eth0 PROTO=6 203.167.117.88:1053
209.61.158.13:80 L=59 S=0x00 I=38406 F=0x4000 T=106 (#1) 
Apr  8 22:38:54 ickis kernel: Packet log: input DENY eth0 PROTO=6 203.167.117.88:1076
209.61.158.13:31 L=48 S=0x00 I=38662 F=0x4000 T=106 SYN (#1) 
Apr  8 22:38:54 ickis kernel: Packet log: input DENY eth0 PROTO=6 203.167.117.88:1077
209.61.158.13:33 L=48 S=0x00 I=38918 F=0x4000 T=106 SYN (#1) 


can anyone pls tell me what those lines in the log mean?  and how do i stop
it?
and also, how do i block out everything coming from 203.167.117.0/24?

thanks,
sib

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