From: Linus Torvalds <torvalds@linux-foundation.org>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Brian Gerst <brgerst@gmail.com>,
Andy Lutomirski <luto@kernel.org>,
the arch/x86 maintainers <x86@kernel.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
linux-arch <linux-arch@vger.kernel.org>,
Borislav Petkov <bp@alien8.de>, Nadav Amit <nadav.amit@gmail.com>,
Kees Cook <keescook@chromium.org>,
"kernel-hardening@lists.openwall.com"
<kernel-hardening@lists.openwall.com>,
Josh Poimboeuf <jpoimboe@redhat.com>, Jann Horn <jann@thejh.net>,
Heiko Carstens <heiko.carstens@de.ibm.com>
Subject: Re: [PATCH v4 15/29] x86/mm/64: Enable vmapped stacks
Date: Mon, 27 Jun 2016 10:28:12 -0700 [thread overview]
Message-ID: <CA+55aFznPpS8rT_GLdAyHsr80B2FCb2Hm-4b9QTqREMCv6_s-Q@mail.gmail.com> (raw)
In-Reply-To: <CALCETrXVtjPQHx2g_O3HRr-DNLWRpDL3Pftt2peoVrfNGiSucA@mail.gmail.com>
On Mon, Jun 27, 2016 at 8:54 AM, Andy Lutomirski <luto@amacapital.net> wrote:
>
> How about:
>
> tsk_stack = (unsigned long)task_stack_page(tsk);
> if (regs->rsp <= tsk_stack + 7*8 && regs->rsp > tsk_stack - PAGE_SIZE) {
I'm not at all convinced that regs->rsp will be all that reliable
under a double-fault scenario either. I'd be more inclined to trusr
cr2 than the register state.
It's true that double faults can happen for *other* reasons entirely,
and as such it's not clear that %cr2 is reliable either, but since
this is all just about a printout, I'd rather go that way anyway.
Linus
next prev parent reply other threads:[~2016-06-27 17:28 UTC|newest]
Thread overview: 136+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-26 21:55 [PATCH v4 00/29] virtually mapped stacks and thread_info cleanup Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 01/29] bluetooth: Switch SMP to crypto_cipher_encrypt_one() Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
[not found] ` <264af59a3060c2bc2a725cfc66a8fa68219d1c4a.1466974736.git.luto-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
2016-06-27 5:58 ` Marcel Holtmann
2016-06-27 5:58 ` Marcel Holtmann
2016-06-27 8:54 ` Ingo Molnar
2016-06-27 8:54 ` Ingo Molnar
2016-06-27 22:30 ` Marcel Holtmann
2016-06-27 22:30 ` Marcel Holtmann
2016-06-27 22:33 ` Andy Lutomirski
2016-07-04 17:56 ` Marcel Holtmann
2016-07-04 17:56 ` Marcel Holtmann
2016-07-06 13:17 ` Andy Lutomirski
2016-07-06 13:17 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 02/29] rxrpc: Avoid using stack memory in SG lists in rxkad Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 03/29] x86/mm/hotplug: Don't remove PGD entries in remove_pagetable() Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 04/29] x86/cpa: In populate_pgd, don't set the pgd entry until it's populated Andy Lutomirski
2016-06-28 18:48 ` Borislav Petkov
2016-06-28 19:07 ` Andy Lutomirski
2016-06-28 19:07 ` Andy Lutomirski
[not found] ` <cover.1466974736.git.luto-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
2016-06-26 21:55 ` [PATCH v4 05/29] x86/mm: Remove kernel_unmap_pages_in_pgd() and efi_cleanup_page_tables() Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-27 7:19 ` Borislav Petkov
2016-06-27 7:19 ` Borislav Petkov
2016-06-26 21:55 ` [PATCH v4 06/29] mm: Track NR_KERNEL_STACK in KiB instead of number of stacks Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 07/29] mm: Fix memcg stack accounting for sub-page stacks Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 08/29] dma-api: Teach the "DMA-from-stack" check about vmapped stacks Andy Lutomirski
2016-06-30 19:37 ` Borislav Petkov
2016-06-30 19:37 ` Borislav Petkov
2016-07-06 13:20 ` Andy Lutomirski
2016-07-06 13:20 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 09/29] fork: Add generic vmalloced stack support Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-07-01 14:59 ` Borislav Petkov
2016-07-01 14:59 ` Borislav Petkov
2016-07-01 16:30 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 10/29] x86/die: Don't try to recover from an OOPS on a non-default stack Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-07-02 17:24 ` Borislav Petkov
2016-07-02 17:24 ` Borislav Petkov
2016-07-02 18:34 ` Josh Poimboeuf
2016-07-03 9:40 ` Borislav Petkov
2016-07-03 14:25 ` Andy Lutomirski
2016-07-03 14:25 ` Andy Lutomirski
2016-07-03 18:42 ` Borislav Petkov
2016-06-26 21:55 ` [PATCH v4 11/29] x86/dumpstack: When OOPSing, rewind the stack before do_exit Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-07-04 18:45 ` Borislav Petkov
2016-06-26 21:55 ` [PATCH v4 12/29] x86/dumpstack: When dumping stack bytes due to OOPS, start with regs->sp Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 13/29] x86/dumpstack: Try harder to get a call trace on stack overflow Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 14/29] x86/dumpstack/64: Handle faults when printing the "Stack:" part of an OOPS Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 15/29] x86/mm/64: Enable vmapped stacks Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-27 15:01 ` Brian Gerst
2016-06-27 15:01 ` Brian Gerst
2016-06-27 15:12 ` Brian Gerst
2016-06-27 15:22 ` Andy Lutomirski
2016-06-27 15:22 ` Andy Lutomirski
2016-06-27 15:54 ` Andy Lutomirski
2016-06-27 15:54 ` Andy Lutomirski
2016-06-27 16:17 ` Brian Gerst
2016-06-27 16:17 ` Brian Gerst
2016-06-27 16:35 ` Andy Lutomirski
2016-06-27 16:35 ` Andy Lutomirski
2016-06-27 17:09 ` Brian Gerst
2016-06-27 17:23 ` Brian Gerst
2016-06-27 17:28 ` Linus Torvalds [this message]
2016-06-27 17:30 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 16/29] x86/mm: Improve stack-overflow #PF handling Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 17/29] x86: Move uaccess_err and sig_on_uaccess_err to thread_struct Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 18/29] x86: Move addr_limit " Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 19/29] signal: Consolidate {TS,TLF}_RESTORE_SIGMASK code Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 20/29] x86/smp: Remove stack_smp_processor_id() Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 21/29] x86/smp: Remove unnecessary initialization of thread_info::cpu Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 22/29] x86/asm: Move 'status' from struct thread_info to struct thread_struct Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-26 23:55 ` Brian Gerst
2016-06-27 0:23 ` Andy Lutomirski
2016-06-27 0:36 ` Brian Gerst
2016-06-27 0:40 ` Andy Lutomirski
2016-06-27 0:40 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 23/29] kdb: Use task_cpu() instead of task_thread_info()->cpu Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 24/29] x86/entry: Get rid of pt_regs_to_thread_info() Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 25/29] um: Stop conflating task_struct::stack with thread_info Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-26 23:40 ` Brian Gerst
2016-06-26 23:49 ` Andy Lutomirski
2016-06-26 23:49 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 26/29] sched: Allow putting thread_info into task_struct Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-07-11 10:08 ` [kernel-hardening] " Mark Rutland
2016-07-11 14:55 ` Andy Lutomirski
2016-07-11 14:55 ` Andy Lutomirski
2016-07-11 15:08 ` Mark Rutland
2016-07-11 16:06 ` Linus Torvalds
2016-07-11 16:31 ` [kernel-hardening] " Mark Rutland
2016-07-11 16:31 ` Mark Rutland
2016-07-11 16:42 ` Linus Torvalds
2016-06-26 21:55 ` [PATCH v4 27/29] x86: Move " Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 28/29] sched: Free the stack early if CONFIG_THREAD_INFO_IN_TASK Andy Lutomirski
2016-06-26 21:55 ` Andy Lutomirski
2016-06-27 2:35 ` Andy Lutomirski
2016-06-26 21:55 ` [PATCH v4 29/29] fork: Cache two thread stacks per cpu if CONFIG_VMAP_STACK is set Andy Lutomirski
2016-06-28 7:32 ` [PATCH v4 02/29] rxrpc: Avoid using stack memory in SG lists in rxkad David Howells
2016-06-28 7:37 ` Herbert Xu
2016-06-28 9:07 ` David Howells
2016-06-28 9:45 ` Herbert Xu
2016-06-28 9:45 ` Herbert Xu
2016-06-28 7:41 ` David Howells
2016-06-28 7:41 ` David Howells
2016-06-28 7:52 ` David Howells
2016-06-28 7:55 ` Herbert Xu
2016-06-28 8:54 ` David Howells
2016-06-28 9:43 ` Herbert Xu
2016-06-28 9:43 ` Herbert Xu
2016-06-28 10:00 ` David Howells
2016-06-28 10:00 ` David Howells
2016-06-28 13:23 ` David Howells
2016-06-29 7:06 ` [PATCH v4 00/29] virtually mapped stacks and thread_info cleanup Mika Penttilä
2016-06-29 7:06 ` Mika Penttilä
2016-06-29 17:24 ` Mika Penttilä
2016-06-29 17:24 ` Mika Penttilä
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