Note: This bug is displayed in read-only format because
the product is no longer active in Red Hat Bugzilla.
RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.
Description of problem:
Back on bz 1066517 it was agreed that systemd would base its random-seed size off of the /proc/sys/kernel/random/poolsize value. The formula was as follows:
read from /proc/poolsize = 4096 bits
calculate bytes = 512 bytes.
multiply by stephan's 2:1 ration = 1024 bytes
multiply by a safety factor of 4 (or 8) = 4096 bytes
Version-Release number of selected component (if applicable):
systemd-219-26.el7
How reproducible:
Always
Steps to Reproduce:
1. ls -l /var/lib/systemd/random-seed
Actual results:
512
Expected results:
4096
Additional info:
RHEL 6 correctly sets the size to 4096.
I cannot see any agreement on 4096 in that bugzilla... Also, nobody answered Lennart's final question at https://bugzilla.redhat.com/show_bug.cgi?id=1066517#c73, when he asked what he was supposed to do after all the discussion... The whole point of the change seems to be a "better safe than sorry, but nobody actually knows if it's safer" approach. Is there an available demonstration where people can actually show how much difference it makes to change that particular random seed?
The problem is that the algorithm used to mix the seed into the pool sometimes touches bits and locations more than once. This means a bigger seed is necessary to touch every bit in every location at least once. RHEL7 GA did this right. Somewhere along the way, a patch in systemd was dropped and now we have a regression.
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.
https://access.redhat.com/errata/RHBA-2017:2297