+++ This bug was initially created as a clone of Bug #458016 +++ Description of problem: Stephen Hemminger wrote a patch to improve random32() seeding. The rationale is: * use u32 consistently * no need to do LCG on values from (better) get_random_bytes * use more data from get_random_bytes for secondary seeding * don't reduce state space on srandom32() * enforce state variable initialization restrictions --- Additional comment from eteo on 2008-08-06 02:18:35 EDT --- Proposed upstream patch: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=697f8d0348a652593d195a13dd1067d9df911a82 --- Additional comment from eteo on 2008-08-06 02:22:51 EDT --- Created an attachment (id=313529) Upstream patch for this issue
It needs the following upstream patch as well: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=61407f80f72970d52d4339f81c6c3cd03f4ca0f0
Updating PM score.
This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release.
What does this "random32: seeding improvement" patch improve? See pngs in attachments: 78.0.1 doesn't have this patch, and 78.10.EL.bz458022 has. I don't see much difference...
Created attachment 317070 [details] port numbers distribution on kernel w/o patch
Created attachment 317071 [details] port numbers distribution on kernel with patch
Created attachment 317072 [details] backported patch
Created attachment 317073 [details] test case (generates script for octave + gnuplot)
Created attachment 317074 [details] port numbers distribution on kernel w/o patch
Created attachment 317075 [details] port numbers distribution on kernel with patch
(In reply to comment #4) > What does this "random32: seeding improvement" patch improve? See pngs in > attachments: 78.0.1 doesn't have this patch, and 78.10.EL.bz458022 has. I don't > see much difference... This was briefly discussed in our internal kernel mailing list. As spoken in IRC, can you follow-up with Dave wrt your findings? Thanks Vitaly.
Committed in 88.EL . RPMS are available at http://people.redhat.com/vgoyal/rhel4/
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHSA-2009-1024.html