I found a patch in the lkml thread at http://www.mail-archive.com/linux-
[EMAIL PROTECTED]/msg213559.html.  This is essentially a one line
patch to the kernel that has been well tested since it is Hardy also.  I
think it'd be worthwhile to get this fixed in Gutsy.  The patch follows:

Problem spotted by Denys Fedoryshchenko

Signed-off-by: Eric Dumazet <[EMAIL PROTECTED]>

--- linux-2.6.22/drivers/char/random.c  2007-10-01 10:18:42.000000000 +0200
+++ linux-2.6.22-ed/drivers/char/random.c       2007-10-01 21:47:58.000000000 
+0200
@@ -1550,11 +1550,13 @@ __u32 secure_tcp_sequence_number(__be32 
         *      As close as possible to RFC 793, which
         *      suggests using a 250 kHz clock.
         *      Further reading shows this assumes 2 Mb/s networks.
-        *      For 10 Gb/s Ethernet, a 1 GHz clock is appropriate.
-        *      That's funny, Linux has one built in!  Use it!
-        *      (Networks are faster now - should this be increased?)
+        *      For 10 Mb/s Ethernet, a 1 MHz clock is appropriate.
+        *      For 10 Gb/s Ethernet, a 1 GHz clock should be ok, but
+        *      we also need to limit the resolution so that the u32 seq
+        *      overlaps less than one time per MSL (2 minutes).
+        *      Choosing a clock of 64 ns period is OK. (period of 274 s)
         */
-       seq += ktime_get_real().tv64;
+       seq += ktime_get_real().tv64 >> 6;
 #if 0
        printk("init_seq(%lx, %lx, %d, %d) = %d\n",
               saddr, daddr, sport, dport, seq);

** Changed in: linux-source-2.6.22 (Ubuntu)
   Importance: Undecided => High
     Assignee: (unassigned) => Ubuntu Kernel Team (ubuntu-kernel-team)
       Status: New => Triaged

-- 
network performance and cpu usage in gutsy vs feisty
https://bugs.launchpad.net/bugs/152741
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