From: Steven Rostedt <email@example.com> To: Linus Torvalds <firstname.lastname@example.org> Cc: Kees Cook <email@example.com>, Anna-Maria Gleixner <firstname.lastname@example.org>, Linux Kernel Mailing List <email@example.com>, tcharding <firstname.lastname@example.org> Subject: Re: Hashed pointer issues Date: Mon, 30 Apr 2018 12:41:35 -0400 [thread overview] Message-ID: <email@example.com> (raw) In-Reply-To: <CA+55aFwieC1-nAs+NFq9RTwaR8ef9hWa4MjNBWL41F-8wM49eA@mail.gmail.com> On Mon, 30 Apr 2018 16:31:52 +0000 Linus Torvalds <firstname.lastname@example.org> wrote: > On Mon, Apr 30, 2018 at 9:11 AM Kees Cook <email@example.com> wrote: > > > I (or other folks?) had proposed this before, but, AIUI, Linus remains > > opposed. > > Yeah, I hate this, because it will make people paper over their problems by > just booting with that option. > > I think it should just be fixed. > > Is there really any reason why trace buffers have to be dumped so early > that the entropy hasn't even taken yet? In this case, an RCU stall was triggering and a "dump on oops" would dump the trace buffers, (before entropy was established). > > And if we really want a command line option, can we make that still hash > the pointer, just force the entropy early. That way kernel developers that > test that command line option are still testing the *hashing*, they just > are missing the good entropy. > That may work too. Even with bad entropy, pointers at start up are hard to come by, and I can't see a hacker being able to use them as it only happens once during boot. -- Steve
next prev parent reply other threads:[~2018-04-30 16:41 UTC|newest] Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top 2018-04-30 15:50 Anna-Maria Gleixner 2018-04-30 16:11 ` Kees Cook 2018-04-30 16:31 ` Linus Torvalds 2018-04-30 16:41 ` Steven Rostedt [this message] 2018-04-30 16:57 ` Linus Torvalds 2018-04-30 17:01 ` Linus Torvalds 2018-04-30 17:06 ` Randy Dunlap 2018-04-30 17:12 ` Linus Torvalds 2018-05-01 7:05 ` tcharding 2018-05-03 8:41 ` Geert Uytterhoeven 2018-04-30 18:38 ` Kees Cook 2018-04-30 19:00 ` Linus Torvalds 2018-04-30 19:16 ` Kees Cook 2018-04-30 20:01 ` Linus Torvalds 2018-04-30 20:07 ` Linus Torvalds 2018-04-30 21:23 ` Tobin C. Harding
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