From: Joseph Myers <joseph@codesourcery.com>
To: Paul Eggert <eggert@cs.ucla.edu>
Cc: Florian Weimer <fweimer@redhat.com>, <libc-alpha@sourceware.org>
Subject: Re: [PATCH] Add getrandom implementation [BZ #17252]
Date: Fri, 10 Jun 2016 22:06:00 -0000 [thread overview]
Message-ID: <alpine.DEB.2.20.1606102202290.20503@digraph.polyomino.org.uk> (raw)
In-Reply-To: <be07cb5e-313f-4f52-61e1-6522fe4e4732@cs.ucla.edu>
On Fri, 10 Jun 2016, Paul Eggert wrote:
> How about if we use a simpler implementation instead, one that opens, reads,
> and closes /dev/whatever each time getrandom is called? That would be a bit
> slower slower but would avoid this problem and probably other problems.
That would certainly be my preference. (You still need O_CLOEXEC on the
open, as for all cases where file descriptors are used internally in
glibc, to avoid leaking file descriptors to concurrent fork and exec from
other threads.)
It's in the nature of this code - returning cryptographically-secure
random numbers - to be used in security-critical places. And for such
code, there are advantages to being simple enough to be obviously safe and
not to need lots of complicated defensive code.
--
Joseph S. Myers
joseph@codesourcery.com
next prev parent reply other threads:[~2016-06-10 22:06 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-10 21:03 Florian Weimer
2016-06-10 21:31 ` Joseph Myers
2016-06-10 21:36 ` Joseph Myers
2016-06-10 22:00 ` Paul Eggert
2016-06-10 22:06 ` Joseph Myers [this message]
2016-06-11 11:13 ` Florian Weimer
2016-06-11 20:10 ` Paul Eggert
2016-06-10 22:15 ` Roland McGrath
2016-06-10 22:40 ` Joseph Myers
2016-06-10 22:45 ` Roland McGrath
2016-06-23 17:21 ` Florian Weimer
2016-06-25 21:58 ` Paul Eggert
2016-09-02 22:23 ` Roland McGrath
2016-06-27 15:07 ` [PATCH v2] " Florian Weimer
2016-06-30 9:33 ` Rical Jasan
2016-09-08 9:53 ` Florian Weimer
2016-09-08 10:13 ` Andreas Schwab
2016-09-08 10:28 ` Florian Weimer
2016-09-08 11:58 ` Rical Jasan
2016-09-08 12:36 ` Florian Weimer
2016-06-30 12:03 ` Zack Weinberg
2016-07-13 13:10 ` Nikos Mavrogiannopoulos
2016-11-14 17:45 ` [PATCH v7] getrandom system call wrapper " Florian Weimer
2016-11-14 18:29 ` Zack Weinberg
2016-11-15 20:57 ` Richard Henderson
2016-11-16 15:11 ` Florian Weimer
2016-11-16 15:20 ` Zack Weinberg
2016-11-16 15:52 ` Florian Weimer
2016-11-16 16:41 ` Zack Weinberg
2016-11-17 13:02 ` Florian Weimer
2016-11-17 13:46 ` Zack Weinberg
2016-11-17 13:50 ` Florian Weimer
2016-11-17 13:56 ` Zack Weinberg
2016-11-17 15:24 ` Florian Weimer
2016-11-17 17:16 ` Zack Weinberg
2016-11-18 10:27 ` Szabolcs Nagy
2016-11-18 15:46 ` Torvald Riegel
2016-11-18 18:50 ` Zack Weinberg
2016-11-21 16:57 ` Torvald Riegel
2016-11-21 17:12 ` Zack Weinberg
2016-11-21 17:30 ` Torvald Riegel
2016-11-21 17:34 ` Florian Weimer
2016-11-29 8:24 ` Florian Weimer
2016-11-16 18:02 ` Torvald Riegel
2016-11-16 19:53 ` Adhemerval Zanella
2016-11-17 12:52 ` Torvald Riegel
2016-11-18 8:28 ` Szabolcs Nagy
2016-11-18 14:21 ` Torvald Riegel
2016-11-18 15:13 ` Florian Weimer
2016-11-18 16:04 ` Torvald Riegel
2016-11-29 8:16 ` Florian Weimer
2016-11-29 13:56 ` Torvald Riegel
2016-11-29 14:40 ` Florian Weimer
2016-11-29 15:23 ` Torvald Riegel
2016-11-29 15:32 ` Florian Weimer
2016-11-29 15:54 ` Zack Weinberg
2016-11-29 17:53 ` Paul Eggert
2016-11-29 18:11 ` Florian Weimer
2016-11-29 19:37 ` Paul Eggert
2016-11-30 6:09 ` Florian Weimer
2016-11-17 6:21 ` Mike Frysinger
2016-11-18 13:21 ` Florian Weimer
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