Theodore Ts'o
775f4b297b
random: make 'add_interrupt_randomness()' do something sane ...
We've been moving away from add_interrupt_randomness() for various
reasons: it's too expensive to do on every interrupt, and flooding the
CPU with interrupts could theoretically cause bogus floods of entropy
from a somewhat externally controllable source.
This solves both problems by limiting the actual randomness addition
to just once a second or after 64 interrupts, whicever comes first.
During that time, the interrupt cycle data is buffered up in a per-cpu
pool. Also, we make sure the the nonblocking pool used by urandom is
initialized before we start feeding the normal input pool. This
assures that /dev/urandom is returning unpredictable data as soon as
possible.
(Based on an original patch by Linus, but significantly modified by
tytso.)
Tested-by: Eric Wustrow <ewust@umich.edu>
Reported-by: Eric Wustrow <ewust@umich.edu>
Reported-by: Nadia Heninger <nadiah@cs.ucsd.edu>
Reported-by: Zakir Durumeric <zakir@umich.edu>
Reported-by: J. Alex Halderman <jhalderm@umich.edu>.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
2012-07-14 20:17:28 -04:00
2012-03-06 18:46:57 +01:00
2012-03-06 18:46:49 +01:00
2012-04-05 15:25:50 -07:00
2012-07-14 20:17:28 -04:00
2010-08-12 11:27:17 +02:00
2011-10-24 14:09:16 +02:00
2012-05-20 17:27:10 +02:00
2012-05-20 17:27:10 +02:00
2012-05-20 17:27:11 +02:00
2012-05-20 17:27:13 +02:00
2011-10-31 19:32:04 -04:00
2011-12-20 18:50:55 +01:00
2012-05-20 17:27:07 +02:00
2012-05-01 12:00:23 +02:00
2012-05-01 12:00:21 +02:00
2011-12-20 18:50:56 +01:00
2012-05-29 11:53:11 -07:00
2012-05-20 17:27:03 +02:00
2012-05-20 17:27:03 +02:00
2011-05-26 19:45:13 +02:00
2012-06-01 02:04:46 +02:00
2012-03-06 18:46:56 +01:00
2012-01-09 00:37:38 +01:00
2011-03-31 11:26:23 -03:00
2011-03-27 00:09:52 +01:00
2011-03-27 00:09:52 +01:00
2011-07-08 21:14:44 -07:00
2012-05-01 12:00:23 +02:00
2012-05-01 12:00:21 +02:00
2012-01-09 00:37:36 +01:00
2012-05-29 11:53:11 -07:00
2012-05-20 17:27:14 +02:00
2012-05-20 17:27:02 +02:00
2012-05-09 17:20:09 +02:00
2012-05-20 17:27:03 +02:00
2012-05-29 11:53:11 -07:00
2011-11-25 23:24:45 +04:00
2012-01-09 01:03:34 +01:00
2012-04-17 14:51:47 +01:00
2012-04-17 14:51:47 +01:00
2011-03-27 00:09:51 +01:00
2012-01-09 00:37:36 +01:00
2012-05-20 17:27:06 +02:00
2012-05-20 17:27:06 +02:00
2012-05-29 11:53:11 -07:00
2012-05-01 12:35:41 +02:00
2012-05-01 12:35:40 +02:00
2012-05-01 12:35:40 +02:00
2012-03-28 15:58:21 -07:00
2012-03-28 15:58:21 -07:00
2011-11-03 09:40:51 -07:00
2012-03-06 18:46:47 +01:00
2012-05-01 12:00:24 +02:00
2012-05-18 16:54:47 +01:00
2012-01-09 00:37:31 +01:00
2012-05-20 17:27:04 +02:00
2012-03-06 18:46:51 +01:00
2012-03-06 18:46:51 +01:00
2011-05-26 19:45:28 +02:00
2011-05-26 19:45:28 +02:00
2012-03-16 20:05:45 +01:00
2012-05-09 17:50:29 +02:00
2012-05-01 12:00:21 +02:00
2012-05-09 17:50:53 +02:00
2012-03-06 18:46:35 +01:00
2012-03-16 20:37:47 +01:00
2012-05-09 15:34:28 +02:00
2012-06-20 14:39:36 -07:00
2012-06-20 14:39:36 -07:00
2012-03-06 18:46:38 +01:00
2012-01-09 00:37:44 +01:00
2012-01-09 00:37:31 +01:00
2011-10-24 14:09:09 +02:00
2012-01-09 00:37:31 +01:00
2011-05-26 19:45:04 +02:00
2012-01-09 00:37:31 +01:00
2012-01-09 00:37:37 +01:00
2010-12-29 08:16:46 -02:00
2011-10-31 19:32:05 -04:00
2011-05-26 19:45:11 +02:00
2010-10-29 00:30:29 +02:00
2012-05-04 13:25:16 +01:00
2011-01-14 12:37:36 +01:00
2012-05-29 11:53:11 -07:00
2012-05-20 17:27:00 +02:00
2012-05-20 17:27:08 +02:00
2012-05-22 23:49:52 +02:00
2012-04-05 16:58:23 -07:00
2012-03-06 18:46:47 +01:00
2011-07-31 23:28:25 +02:00
2011-07-31 23:28:22 +02:00
2012-01-09 00:37:31 +01:00
2012-01-09 00:37:31 +01:00
2012-05-09 18:02:51 +02:00
2012-01-09 00:37:31 +01:00
2012-02-13 10:00:35 +00:00
2012-03-22 13:05:34 +01:00
2011-07-31 23:28:27 +02:00
2012-05-23 16:24:14 +02:00
2012-05-20 17:27:12 +02:00
2012-05-20 17:26:58 +02:00
2012-03-22 13:04:33 +01:00
2012-02-18 23:15:44 +00:00
2012-02-18 23:15:43 +00:00
2012-02-18 23:15:43 +00:00
2011-03-31 11:26:23 -03:00
2012-05-01 12:00:21 +02:00
2011-10-31 19:32:04 -04:00
2012-05-20 17:27:07 +02:00
2012-05-20 17:27:07 +02:00
2012-02-22 13:57:05 +00:00
2012-05-20 17:27:14 +02:00
2009-09-17 09:46:59 +02:00
2012-03-28 13:56:35 -07:00
2012-05-07 11:32:08 +02:00
2011-09-06 16:37:58 +02:00
2012-05-20 17:27:09 +02:00
2012-03-06 18:46:34 +01:00
2009-12-13 19:21:53 +01:00
2012-05-20 17:27:05 +02:00
2012-05-07 11:32:09 +02:00
2012-05-15 18:57:25 +01:00
2012-05-01 12:00:21 +02:00
2011-12-13 00:11:13 +08:00
775f4b297b