All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Yu, Yu-cheng" <yu-cheng.yu@intel.com>
To: Thomas Gleixner <tglx@linutronix.de>,
	LKML <linux-kernel@vger.kernel.org>
Cc: x86@kernel.org, Andy Lutomirski <luto@kernel.org>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	Fenghua Yu <fenghua.yu@intel.com>,
	Tony Luck <tony.luck@intel.com>
Subject: Re: [patch 0/8] x86/fpu: Mop up XSAVES and related damage
Date: Wed, 2 Jun 2021 14:28:00 -0700	[thread overview]
Message-ID: <9c5c90bf-fbf6-7e45-4668-2f40f11e8b36@intel.com> (raw)
In-Reply-To: <20210602095543.149814064@linutronix.de>

On 6/2/2021 2:55 AM, Thomas Gleixner wrote:
> syszbot reported a warnon for XRSTOR raising #GP:
> 
>   https://lore.kernel.org/r/0000000000004c453905c30f8334@google.com
> 
> with a syzcaller reproducer and a conclusive bisect result.
> 
> It took a while to destill a simple C reproducer out of it which allowed to
> pin point the root cause: The recent addition of supervisor XSTATEs broke
> the signal restore path for the case where the signal handler wreckaged the
> XSTATE on stack because it does not sanitize the XSTATE header which causes
> a subsequent XRSTOR to fail and #GP.
> 
> The following series addresses the problem and fixes related issues which
> were found while inspecting the related changes.
> 
> Thanks to Andy and Dave for working on this with me!
> 
> Thanks,
> 
> 	tglx
> ---
>   arch/x86/include/asm/fpu/xstate.h                     |    4
>   arch/x86/kernel/fpu/core.c                            |   62 ++++++---
>   arch/x86/kernel/fpu/regset.c                          |   43 ++----
>   arch/x86/kernel/fpu/signal.c                          |   30 +++-
>   arch/x86/kernel/fpu/xstate.c                          |   95 +++++----------
>   b/tools/testing/selftests/x86/corrupt_xstate_header.c |  114 ++++++++++++++++++
>   tools/testing/selftests/x86/Makefile                  |    3
>   7 files changed, 234 insertions(+), 117 deletions(-)
> 

With the series applied, glibc pkey test fails sometimes.  I will try to 
find out the cause.

The test:

https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/tst-pkey.c

The output:

error: ../sysdeps/unix/sysv/linux/tst-pkey.c:161: not true: 
!check_page_access (i, false)
error: ../sysdeps/unix/sysv/linux/tst-pkey.c:162: not true: 
!check_page_access (i, true)
error: ../sysdeps/unix/sysv/linux/tst-pkey.c:161: not true: 
!check_page_access (i, false)
error: ../sysdeps/unix/sysv/linux/tst-pkey.c:162: not true: 
!check_page_access (i, true)
error: ../sysdeps/unix/sysv/linux/tst-pkey.c:161: not true: 
!check_page_access (i, false)
error: ../sysdeps/unix/sysv/linux/tst-pkey.c:162: not true: 
!check_page_access (i, true)
../sysdeps/unix/sysv/linux/tst-pkey.c:238: numeric comparison failure
    left: 0 (0x0); from: result->access_rights[i]
   right: 1 (0x1); from: PKEY_DISABLE_ACCESS
../sysdeps/unix/sysv/linux/tst-pkey.c:238: numeric comparison failure
    left: 0 (0x0); from: result->access_rights[i]
   right: 1 (0x1); from: PKEY_DISABLE_ACCESS
../sysdeps/unix/sysv/linux/tst-pkey.c:238: numeric comparison failure
    left: 0 (0x0); from: result->access_rights[i]
   right: 1 (0x1); from: PKEY_DISABLE_ACCESS
../sysdeps/unix/sysv/linux/tst-pkey.c:242: numeric comparison failure
    left: 0 (0x0); from: result->access_rights[i]
   right: 1 (0x1); from: PKEY_DISABLE_ACCESS
../sysdeps/unix/sysv/linux/tst-pkey.c:242: numeric comparison failure
    left: 0 (0x0); from: result->access_rights[i]
   right: 1 (0x1); from: PKEY_DISABLE_ACCESS
../sysdeps/unix/sysv/linux/tst-pkey.c:242: numeric comparison failure
    left: 0 (0x0); from: result->access_rights[i]
   right: 1 (0x1); from: PKEY_DISABLE_ACCESS
error: 12 test failures

  parent reply	other threads:[~2021-06-02 21:28 UTC|newest]

Thread overview: 33+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-02  9:55 [patch 0/8] x86/fpu: Mop up XSAVES and related damage Thomas Gleixner
2021-06-02  9:55 ` [patch 1/8] selftests/x86: Test signal frame XSTATE header corruption handling Thomas Gleixner
2021-06-02 12:38   ` Borislav Petkov
2021-06-02 14:15     ` Thomas Gleixner
2021-06-03 13:16       ` Shuah Khan
2021-06-02 15:59   ` [patch V2 " Thomas Gleixner
2021-06-02 16:02     ` [patch V2a " Thomas Gleixner
2021-06-02  9:55 ` [patch 2/8] x86/fpu: Prevent state corruption in __fpu__restore_sig() Thomas Gleixner
2021-06-02 13:12   ` Borislav Petkov
2021-06-02 14:46     ` Thomas Gleixner
2021-06-02 15:58   ` [patch V2 " Thomas Gleixner
2021-06-02  9:55 ` [patch 3/8] x86/fpu: Invalidate FPU state after a failed XRSTOR from a user buffer Thomas Gleixner
2021-06-02 15:06   ` Borislav Petkov
2021-06-03 17:30     ` Andy Lutomirski
2021-06-03 19:28       ` Borislav Petkov
2021-06-02  9:55 ` [patch 4/8] x86/fpu: Limit xstate copy size in xstateregs_set() Thomas Gleixner
2021-06-02 17:44   ` Borislav Petkov
2021-06-02  9:55 ` [patch 5/8] x86/fpu: Sanitize xstateregs_set() Thomas Gleixner
2021-06-02 16:01   ` [patch V2 " Thomas Gleixner
2021-06-03 11:32     ` Borislav Petkov
2021-06-03 17:24   ` [patch " Andy Lutomirski
2021-06-02  9:55 ` [patch 6/8] x86/fpu: Add address range checks to copy_user_to_xstate() Thomas Gleixner
2021-06-02  9:55 ` [patch 7/8] x86/fpu: Clean up the fpu__clear() variants Thomas Gleixner
2021-06-02  9:55 ` [patch 8/8] x86/fpu: Deduplicate copy_xxx_to_xstate() Thomas Gleixner
2021-06-03 16:56   ` Andy Lutomirski
2021-06-02 21:28 ` Yu, Yu-cheng [this message]
2021-06-04 14:05   ` [patch 0/8] x86/fpu: Mop up XSAVES and related damage Thomas Gleixner
2021-06-04 16:27     ` Yu, Yu-cheng
2021-06-04 17:46     ` Dave Hansen
2021-06-04 18:14       ` Thomas Gleixner
2021-06-04 22:04 ` Dave Hansen
2021-06-05 10:18   ` Thomas Gleixner
2021-06-05 11:56     ` Thomas Gleixner

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=9c5c90bf-fbf6-7e45-4668-2f40f11e8b36@intel.com \
    --to=yu-cheng.yu@intel.com \
    --cc=dave.hansen@linux.intel.com \
    --cc=fenghua.yu@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luto@kernel.org \
    --cc=tglx@linutronix.de \
    --cc=tony.luck@intel.com \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.