* BUG: optimized kprobes illegal instructions in v4.19 stable kernels
@ 2019-02-04 19:15 Mathieu Desnoyers
2019-02-05 15:06 ` Kees Cook
2019-02-06 11:48 ` David Laight
0 siblings, 2 replies; 13+ messages in thread
From: Mathieu Desnoyers @ 2019-02-04 19:15 UTC (permalink / raw)
To: Kees Cook
Cc: William Cohen, stable, Laura Abbott, Masami Hiramatsu,
Russell King, linux-kernel, lttng, lttng-dev
Hi,
I notice this commit as a possible culprit of the illegal instructions my lttng
users are noticing on arm32 when using kprobes on a v4.19.13 Linux kernel
in a Yocto environment [1]. They were able to reproduce the issue with perf
as well.
commit e46daee53bb50bde38805f1823a182979724c229
Author: Kees Cook <keescook@chromium.org>
Date: Tue Oct 30 22:12:56 2018 +0100
ARM: 8806/1: kprobes: Fix false positive with FORTIFY_SOURCE
I *think* the intent there was to do
- memcpy(code, &optprobe_template_entry,
+ memcpy(code, (unsigned long *)&optprobe_template_entry,
But if you look at the commit, the "&" seems to have been stripped away,
which happens to change the behavior significantly.
Has this change ever been runtime-tested ?
It has been backported to:
- 4.19 stable as commit 3fe0c68aea21
- 4.14 stable as commit f9e0bc710347
Thanks,
Mathieu
[1] https://bugs.lttng.org/issues/1174
--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: BUG: optimized kprobes illegal instructions in v4.19 stable kernels
2019-02-04 19:15 BUG: optimized kprobes illegal instructions in v4.19 stable kernels Mathieu Desnoyers
@ 2019-02-05 15:06 ` Kees Cook
2019-02-06 4:41 ` Masami Hiramatsu
2019-02-06 11:48 ` David Laight
1 sibling, 1 reply; 13+ messages in thread
From: Kees Cook @ 2019-02-05 15:06 UTC (permalink / raw)
To: Mathieu Desnoyers
Cc: William Cohen, # 3.4.x, Laura Abbott, Masami Hiramatsu,
Russell King, linux-kernel, lttng, lttng-dev
On Mon, Feb 4, 2019 at 7:15 PM Mathieu Desnoyers
<mathieu.desnoyers@efficios.com> wrote:
>
> Hi,
>
> I notice this commit as a possible culprit of the illegal instructions my lttng
> users are noticing on arm32 when using kprobes on a v4.19.13 Linux kernel
> in a Yocto environment [1]. They were able to reproduce the issue with perf
> as well.
>
> commit e46daee53bb50bde38805f1823a182979724c229
> Author: Kees Cook <keescook@chromium.org>
> Date: Tue Oct 30 22:12:56 2018 +0100
>
> ARM: 8806/1: kprobes: Fix false positive with FORTIFY_SOURCE
>
> I *think* the intent there was to do
>
> - memcpy(code, &optprobe_template_entry,
> + memcpy(code, (unsigned long *)&optprobe_template_entry,
>
> But if you look at the commit, the "&" seems to have been stripped away,
> which happens to change the behavior significantly.
Yeah, this was a typo on my part. :(
> Has this change ever been runtime-tested ?
I thought I had, given the details from the original bug report, but
clearly it didn't exercise it.
Thanks for fixing this!
-Kees
>
> It has been backported to:
> - 4.19 stable as commit 3fe0c68aea21
> - 4.14 stable as commit f9e0bc710347
>
> Thanks,
>
> Mathieu
>
> [1] https://bugs.lttng.org/issues/1174
>
> --
> Mathieu Desnoyers
> EfficiOS Inc.
> http://www.efficios.com
--
Kees Cook
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: BUG: optimized kprobes illegal instructions in v4.19 stable kernels
2019-02-05 15:06 ` Kees Cook
@ 2019-02-06 4:41 ` Masami Hiramatsu
2019-02-18 12:26 ` Greg KH
0 siblings, 1 reply; 13+ messages in thread
From: Masami Hiramatsu @ 2019-02-06 4:41 UTC (permalink / raw)
To: Kees Cook
Cc: Mathieu Desnoyers, William Cohen, # 3.4.x, Laura Abbott,
Masami Hiramatsu, Russell King, linux-kernel, lttng, lttng-dev
On Tue, 5 Feb 2019 15:06:10 +0000
Kees Cook <keescook@chromium.org> wrote:
> On Mon, Feb 4, 2019 at 7:15 PM Mathieu Desnoyers
> <mathieu.desnoyers@efficios.com> wrote:
> >
> > Hi,
> >
> > I notice this commit as a possible culprit of the illegal instructions my lttng
> > users are noticing on arm32 when using kprobes on a v4.19.13 Linux kernel
> > in a Yocto environment [1]. They were able to reproduce the issue with perf
> > as well.
> >
> > commit e46daee53bb50bde38805f1823a182979724c229
> > Author: Kees Cook <keescook@chromium.org>
> > Date: Tue Oct 30 22:12:56 2018 +0100
> >
> > ARM: 8806/1: kprobes: Fix false positive with FORTIFY_SOURCE
> >
> > I *think* the intent there was to do
> >
> > - memcpy(code, &optprobe_template_entry,
> > + memcpy(code, (unsigned long *)&optprobe_template_entry,
> >
> > But if you look at the commit, the "&" seems to have been stripped away,
> > which happens to change the behavior significantly.
>
> Yeah, this was a typo on my part. :(
Ah, I thought it had been fixed as same as x86.
On x86, all optprobe_template_* are defined as kprobe_opcode_t [],
but on arm, it still be kprobe_opcode_t.
Hmm, but I think we should use kprobe_opcode_t [] or char[] as asm/sections.h does.
OK, I'll prepare for the change.
Thank you,
>
> > Has this change ever been runtime-tested ?
>
> I thought I had, given the details from the original bug report, but
> clearly it didn't exercise it.
>
> Thanks for fixing this!
>
> -Kees
>
> >
> > It has been backported to:
> > - 4.19 stable as commit 3fe0c68aea21
> > - 4.14 stable as commit f9e0bc710347
> >
> > Thanks,
> >
> > Mathieu
> >
> > [1] https://bugs.lttng.org/issues/1174
> >
> > --
> > Mathieu Desnoyers
> > EfficiOS Inc.
> > http://www.efficios.com
>
>
>
> --
> Kees Cook
--
Masami Hiramatsu <mhiramat@kernel.org>
^ permalink raw reply [flat|nested] 13+ messages in thread
* RE: optimized kprobes illegal instructions in v4.19 stable kernels
2019-02-04 19:15 BUG: optimized kprobes illegal instructions in v4.19 stable kernels Mathieu Desnoyers
2019-02-05 15:06 ` Kees Cook
@ 2019-02-06 11:48 ` David Laight
1 sibling, 0 replies; 13+ messages in thread
From: David Laight @ 2019-02-06 11:48 UTC (permalink / raw)
To: 'Mathieu Desnoyers', Kees Cook
Cc: William Cohen, stable, Laura Abbott, Masami Hiramatsu,
Russell King, linux-kernel, lttng, lttng-dev
From: Mathieu Desnoyers
> Sent: 04 February 2019 19:15
> I notice this commit as a possible culprit of the illegal instructions my lttng
> users are noticing on arm32 when using kprobes on a v4.19.13 Linux kernel
> in a Yocto environment [1]. They were able to reproduce the issue with perf
> as well.
>
> commit e46daee53bb50bde38805f1823a182979724c229
> Author: Kees Cook <keescook@chromium.org>
> Date: Tue Oct 30 22:12:56 2018 +0100
>
> ARM: 8806/1: kprobes: Fix false positive with FORTIFY_SOURCE
>
> I *think* the intent there was to do
>
> - memcpy(code, &optprobe_template_entry,
> + memcpy(code, (unsigned long *)&optprobe_template_entry,
>
> But if you look at the commit, the "&" seems to have been stripped away,
> which happens to change the behavior significantly.
Which is why you shouldn't add casts to shut up compiler warnings ....
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: BUG: optimized kprobes illegal instructions in v4.19 stable kernels
2019-02-06 4:41 ` Masami Hiramatsu
@ 2019-02-18 12:26 ` Greg KH
2019-02-18 14:11 ` Masami Hiramatsu
2019-02-18 14:55 ` Mathieu Desnoyers
0 siblings, 2 replies; 13+ messages in thread
From: Greg KH @ 2019-02-18 12:26 UTC (permalink / raw)
To: Masami Hiramatsu
Cc: Kees Cook, Mathieu Desnoyers, William Cohen, # 3.4.x,
Laura Abbott, Russell King, linux-kernel, lttng, lttng-dev
On Wed, Feb 06, 2019 at 01:41:15PM +0900, Masami Hiramatsu wrote:
> On Tue, 5 Feb 2019 15:06:10 +0000
> Kees Cook <keescook@chromium.org> wrote:
>
> > On Mon, Feb 4, 2019 at 7:15 PM Mathieu Desnoyers
> > <mathieu.desnoyers@efficios.com> wrote:
> > >
> > > Hi,
> > >
> > > I notice this commit as a possible culprit of the illegal instructions my lttng
> > > users are noticing on arm32 when using kprobes on a v4.19.13 Linux kernel
> > > in a Yocto environment [1]. They were able to reproduce the issue with perf
> > > as well.
> > >
> > > commit e46daee53bb50bde38805f1823a182979724c229
> > > Author: Kees Cook <keescook@chromium.org>
> > > Date: Tue Oct 30 22:12:56 2018 +0100
> > >
> > > ARM: 8806/1: kprobes: Fix false positive with FORTIFY_SOURCE
> > >
> > > I *think* the intent there was to do
> > >
> > > - memcpy(code, &optprobe_template_entry,
> > > + memcpy(code, (unsigned long *)&optprobe_template_entry,
> > >
> > > But if you look at the commit, the "&" seems to have been stripped away,
> > > which happens to change the behavior significantly.
> >
> > Yeah, this was a typo on my part. :(
>
> Ah, I thought it had been fixed as same as x86.
> On x86, all optprobe_template_* are defined as kprobe_opcode_t [],
> but on arm, it still be kprobe_opcode_t.
>
> Hmm, but I think we should use kprobe_opcode_t [] or char[] as asm/sections.h does.
> OK, I'll prepare for the change.
Did this ever get fixed in Linus's tree? If so, what is the git commit
id, I can't seem to find anything...
thanks,
greg k-h
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: BUG: optimized kprobes illegal instructions in v4.19 stable kernels
2019-02-18 12:26 ` Greg KH
@ 2019-02-18 14:11 ` Masami Hiramatsu
2019-02-18 14:55 ` Mathieu Desnoyers
1 sibling, 0 replies; 13+ messages in thread
From: Masami Hiramatsu @ 2019-02-18 14:11 UTC (permalink / raw)
To: Greg KH
Cc: Kees Cook, Mathieu Desnoyers, William Cohen, # 3.4.x,
Laura Abbott, Russell King, linux-kernel, lttng, lttng-dev
On Mon, 18 Feb 2019 13:26:31 +0100
Greg KH <gregkh@linuxfoundation.org> wrote:
> On Wed, Feb 06, 2019 at 01:41:15PM +0900, Masami Hiramatsu wrote:
> > On Tue, 5 Feb 2019 15:06:10 +0000
> > Kees Cook <keescook@chromium.org> wrote:
> >
> > > On Mon, Feb 4, 2019 at 7:15 PM Mathieu Desnoyers
> > > <mathieu.desnoyers@efficios.com> wrote:
> > > >
> > > > Hi,
> > > >
> > > > I notice this commit as a possible culprit of the illegal instructions my lttng
> > > > users are noticing on arm32 when using kprobes on a v4.19.13 Linux kernel
> > > > in a Yocto environment [1]. They were able to reproduce the issue with perf
> > > > as well.
> > > >
> > > > commit e46daee53bb50bde38805f1823a182979724c229
> > > > Author: Kees Cook <keescook@chromium.org>
> > > > Date: Tue Oct 30 22:12:56 2018 +0100
> > > >
> > > > ARM: 8806/1: kprobes: Fix false positive with FORTIFY_SOURCE
> > > >
> > > > I *think* the intent there was to do
> > > >
> > > > - memcpy(code, &optprobe_template_entry,
> > > > + memcpy(code, (unsigned long *)&optprobe_template_entry,
> > > >
> > > > But if you look at the commit, the "&" seems to have been stripped away,
> > > > which happens to change the behavior significantly.
> > >
> > > Yeah, this was a typo on my part. :(
> >
> > Ah, I thought it had been fixed as same as x86.
> > On x86, all optprobe_template_* are defined as kprobe_opcode_t [],
> > but on arm, it still be kprobe_opcode_t.
> >
> > Hmm, but I think we should use kprobe_opcode_t [] or char[] as asm/sections.h does.
> > OK, I'll prepare for the change.
>
> Did this ever get fixed in Linus's tree? If so, what is the git commit
> id, I can't seem to find anything...
I would like to wait for picking up Mathieu's patch which I acked, since
it is simpler and minimum fix.
https://patchwork.kernel.org/patch/10797511/
After this, I will send my update to change the optprobe_template_*
definitions which will involves wider code, and need to be tested.
Thank you,
--
Masami Hiramatsu <mhiramat@kernel.org>
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: BUG: optimized kprobes illegal instructions in v4.19 stable kernels
2019-02-18 12:26 ` Greg KH
2019-02-18 14:11 ` Masami Hiramatsu
@ 2019-02-18 14:55 ` Mathieu Desnoyers
2019-02-21 20:02 ` Mathieu Desnoyers
1 sibling, 1 reply; 13+ messages in thread
From: Mathieu Desnoyers @ 2019-02-18 14:55 UTC (permalink / raw)
To: Greg Kroah-Hartman, Linus Torvalds
Cc: Masami Hiramatsu, Kees Cook, William Cohen, stable, Laura Abbott,
Russell King, linux-kernel, lttng, lttng-dev
----- On Feb 18, 2019, at 7:26 AM, Greg Kroah-Hartman gregkh@linuxfoundation.org wrote:
> On Wed, Feb 06, 2019 at 01:41:15PM +0900, Masami Hiramatsu wrote:
>> On Tue, 5 Feb 2019 15:06:10 +0000
>> Kees Cook <keescook@chromium.org> wrote:
>>
>> > On Mon, Feb 4, 2019 at 7:15 PM Mathieu Desnoyers
>> > <mathieu.desnoyers@efficios.com> wrote:
>> > >
>> > > Hi,
>> > >
>> > > I notice this commit as a possible culprit of the illegal instructions my lttng
>> > > users are noticing on arm32 when using kprobes on a v4.19.13 Linux kernel
>> > > in a Yocto environment [1]. They were able to reproduce the issue with perf
>> > > as well.
>> > >
>> > > commit e46daee53bb50bde38805f1823a182979724c229
>> > > Author: Kees Cook <keescook@chromium.org>
>> > > Date: Tue Oct 30 22:12:56 2018 +0100
>> > >
>> > > ARM: 8806/1: kprobes: Fix false positive with FORTIFY_SOURCE
>> > >
>> > > I *think* the intent there was to do
>> > >
>> > > - memcpy(code, &optprobe_template_entry,
>> > > + memcpy(code, (unsigned long *)&optprobe_template_entry,
>> > >
>> > > But if you look at the commit, the "&" seems to have been stripped away,
>> > > which happens to change the behavior significantly.
>> >
>> > Yeah, this was a typo on my part. :(
>>
>> Ah, I thought it had been fixed as same as x86.
>> On x86, all optprobe_template_* are defined as kprobe_opcode_t [],
>> but on arm, it still be kprobe_opcode_t.
>>
>> Hmm, but I think we should use kprobe_opcode_t [] or char[] as asm/sections.h
>> does.
>> OK, I'll prepare for the change.
>
> Did this ever get fixed in Linus's tree? If so, what is the git commit
> id, I can't seem to find anything...
It seems to still be in the arm patch tracking system:
https://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=8834/1
If I understand its status correctly, it is applied to the arm tree, but
perhaps it has not been pulled by Linus yet ? The code is still broken
in Linus' master.
It would be important to get this arm kprobes fix upstream before 5.0
final.
Thanks,
Mathieu
--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: BUG: optimized kprobes illegal instructions in v4.19 stable kernels
2019-02-18 14:55 ` Mathieu Desnoyers
@ 2019-02-21 20:02 ` Mathieu Desnoyers
2019-02-22 0:10 ` Russell King - ARM Linux admin
0 siblings, 1 reply; 13+ messages in thread
From: Mathieu Desnoyers @ 2019-02-21 20:02 UTC (permalink / raw)
To: Arnd Bergmann, Russell King, Linus Torvalds
Cc: Masami Hiramatsu, Kees Cook, William Cohen, stable, Laura Abbott,
linux-kernel, lttng, Greg Kroah-Hartman, Thomas Gleixner
Hi Arnd, Russell, Linus,
Can we ensure the arm32 kprobes fix I submitted gets upstream before 5.0 final ?
It takes care of an illegal instruction issue with optimized kprobes on arm32.
Here is the current state of default kprobes configuration on arm32:
using them will trigger illegal instruction OOPS on v5.0-rc7, 4.19.24,
v4.14.102.
My fix is in "accepted" state in the arm patch tracking system:
https://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=8834/1
Should I send it directly to Linus as well ?
Thanks,
Mathieu
----- On Feb 18, 2019, at 9:55 AM, Mathieu Desnoyers mathieu.desnoyers@efficios.com wrote:
> ----- On Feb 18, 2019, at 7:26 AM, Greg Kroah-Hartman gregkh@linuxfoundation.org
> wrote:
>
>> On Wed, Feb 06, 2019 at 01:41:15PM +0900, Masami Hiramatsu wrote:
>>> On Tue, 5 Feb 2019 15:06:10 +0000
>>> Kees Cook <keescook@chromium.org> wrote:
>>>
>>> > On Mon, Feb 4, 2019 at 7:15 PM Mathieu Desnoyers
>>> > <mathieu.desnoyers@efficios.com> wrote:
>>> > >
>>> > > Hi,
>>> > >
>>> > > I notice this commit as a possible culprit of the illegal instructions my lttng
>>> > > users are noticing on arm32 when using kprobes on a v4.19.13 Linux kernel
>>> > > in a Yocto environment [1]. They were able to reproduce the issue with perf
>>> > > as well.
>>> > >
>>> > > commit e46daee53bb50bde38805f1823a182979724c229
>>> > > Author: Kees Cook <keescook@chromium.org>
>>> > > Date: Tue Oct 30 22:12:56 2018 +0100
>>> > >
>>> > > ARM: 8806/1: kprobes: Fix false positive with FORTIFY_SOURCE
>>> > >
>>> > > I *think* the intent there was to do
>>> > >
>>> > > - memcpy(code, &optprobe_template_entry,
>>> > > + memcpy(code, (unsigned long *)&optprobe_template_entry,
>>> > >
>>> > > But if you look at the commit, the "&" seems to have been stripped away,
>>> > > which happens to change the behavior significantly.
>>> >
>>> > Yeah, this was a typo on my part. :(
>>>
>>> Ah, I thought it had been fixed as same as x86.
>>> On x86, all optprobe_template_* are defined as kprobe_opcode_t [],
>>> but on arm, it still be kprobe_opcode_t.
>>>
>>> Hmm, but I think we should use kprobe_opcode_t [] or char[] as asm/sections.h
>>> does.
>>> OK, I'll prepare for the change.
>>
>> Did this ever get fixed in Linus's tree? If so, what is the git commit
>> id, I can't seem to find anything...
>
> It seems to still be in the arm patch tracking system:
>
> https://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=8834/1
>
> If I understand its status correctly, it is applied to the arm tree, but
> perhaps it has not been pulled by Linus yet ? The code is still broken
> in Linus' master.
>
> It would be important to get this arm kprobes fix upstream before 5.0
> final.
>
> Thanks,
>
> Mathieu
>
>
> --
> Mathieu Desnoyers
> EfficiOS Inc.
> http://www.efficios.com
--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: BUG: optimized kprobes illegal instructions in v4.19 stable kernels
2019-02-21 20:02 ` Mathieu Desnoyers
@ 2019-02-22 0:10 ` Russell King - ARM Linux admin
2019-02-22 0:17 ` Mathieu Desnoyers
0 siblings, 1 reply; 13+ messages in thread
From: Russell King - ARM Linux admin @ 2019-02-22 0:10 UTC (permalink / raw)
To: Mathieu Desnoyers
Cc: Arnd Bergmann, Linus Torvalds, Masami Hiramatsu, Kees Cook,
William Cohen, stable, Laura Abbott, linux-kernel, lttng,
Greg Kroah-Hartman, Thomas Gleixner
On Thu, Feb 21, 2019 at 03:02:57PM -0500, Mathieu Desnoyers wrote:
> Hi Arnd, Russell, Linus,
>
> Can we ensure the arm32 kprobes fix I submitted gets upstream before 5.0 final ?
> It takes care of an illegal instruction issue with optimized kprobes on arm32.
>
> Here is the current state of default kprobes configuration on arm32:
> using them will trigger illegal instruction OOPS on v5.0-rc7, 4.19.24,
> v4.14.102.
>
> My fix is in "accepted" state in the arm patch tracking system:
>
> https://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=8834/1
>
> Should I send it directly to Linus as well ?
Accepted means it's in my tree pending to be sent to Linus. It should
now be in mainline. Have you checked?
>
> Thanks,
>
> Mathieu
>
> ----- On Feb 18, 2019, at 9:55 AM, Mathieu Desnoyers mathieu.desnoyers@efficios.com wrote:
>
> > ----- On Feb 18, 2019, at 7:26 AM, Greg Kroah-Hartman gregkh@linuxfoundation.org
> > wrote:
> >
> >> On Wed, Feb 06, 2019 at 01:41:15PM +0900, Masami Hiramatsu wrote:
> >>> On Tue, 5 Feb 2019 15:06:10 +0000
> >>> Kees Cook <keescook@chromium.org> wrote:
> >>>
> >>> > On Mon, Feb 4, 2019 at 7:15 PM Mathieu Desnoyers
> >>> > <mathieu.desnoyers@efficios.com> wrote:
> >>> > >
> >>> > > Hi,
> >>> > >
> >>> > > I notice this commit as a possible culprit of the illegal instructions my lttng
> >>> > > users are noticing on arm32 when using kprobes on a v4.19.13 Linux kernel
> >>> > > in a Yocto environment [1]. They were able to reproduce the issue with perf
> >>> > > as well.
> >>> > >
> >>> > > commit e46daee53bb50bde38805f1823a182979724c229
> >>> > > Author: Kees Cook <keescook@chromium.org>
> >>> > > Date: Tue Oct 30 22:12:56 2018 +0100
> >>> > >
> >>> > > ARM: 8806/1: kprobes: Fix false positive with FORTIFY_SOURCE
> >>> > >
> >>> > > I *think* the intent there was to do
> >>> > >
> >>> > > - memcpy(code, &optprobe_template_entry,
> >>> > > + memcpy(code, (unsigned long *)&optprobe_template_entry,
> >>> > >
> >>> > > But if you look at the commit, the "&" seems to have been stripped away,
> >>> > > which happens to change the behavior significantly.
> >>> >
> >>> > Yeah, this was a typo on my part. :(
> >>>
> >>> Ah, I thought it had been fixed as same as x86.
> >>> On x86, all optprobe_template_* are defined as kprobe_opcode_t [],
> >>> but on arm, it still be kprobe_opcode_t.
> >>>
> >>> Hmm, but I think we should use kprobe_opcode_t [] or char[] as asm/sections.h
> >>> does.
> >>> OK, I'll prepare for the change.
> >>
> >> Did this ever get fixed in Linus's tree? If so, what is the git commit
> >> id, I can't seem to find anything...
> >
> > It seems to still be in the arm patch tracking system:
> >
> > https://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=8834/1
> >
> > If I understand its status correctly, it is applied to the arm tree, but
> > perhaps it has not been pulled by Linus yet ? The code is still broken
> > in Linus' master.
> >
> > It would be important to get this arm kprobes fix upstream before 5.0
> > final.
> >
> > Thanks,
> >
> > Mathieu
> >
> >
> > --
> > Mathieu Desnoyers
> > EfficiOS Inc.
> > http://www.efficios.com
>
> --
> Mathieu Desnoyers
> EfficiOS Inc.
> http://www.efficios.com
>
--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up
According to speedtest.net: 11.9Mbps down 500kbps up
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: BUG: optimized kprobes illegal instructions in v4.19 stable kernels
2019-02-22 0:10 ` Russell King - ARM Linux admin
@ 2019-02-22 0:17 ` Mathieu Desnoyers
2019-02-22 6:25 ` Greg Kroah-Hartman
0 siblings, 1 reply; 13+ messages in thread
From: Mathieu Desnoyers @ 2019-02-22 0:17 UTC (permalink / raw)
To: Russell King, ARM Linux
Cc: Arnd Bergmann, Linus Torvalds, Masami Hiramatsu, Kees Cook,
William Cohen, stable, Laura Abbott, linux-kernel, lttng,
Greg Kroah-Hartman, Thomas Gleixner
----- On Feb 21, 2019, at 7:10 PM, Russell King, ARM Linux linux@armlinux.org.uk wrote:
> On Thu, Feb 21, 2019 at 03:02:57PM -0500, Mathieu Desnoyers wrote:
>> Hi Arnd, Russell, Linus,
>>
>> Can we ensure the arm32 kprobes fix I submitted gets upstream before 5.0 final ?
>> It takes care of an illegal instruction issue with optimized kprobes on arm32.
>>
>> Here is the current state of default kprobes configuration on arm32:
>> using them will trigger illegal instruction OOPS on v5.0-rc7, 4.19.24,
>> v4.14.102.
>>
>> My fix is in "accepted" state in the arm patch tracking system:
>>
>> https://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=8834/1
>>
>> Should I send it directly to Linus as well ?
>
> Accepted means it's in my tree pending to be sent to Linus. It should
> now be in mainline. Have you checked?
Hrm, why did I not see it earlier today... it's embarrassing.
It's there indeed, all is good!
Greg, you should be able to pick it into the stable kernels now.
Thanks,
Mathieu
>
>>
>> Thanks,
>>
>> Mathieu
>>
>> ----- On Feb 18, 2019, at 9:55 AM, Mathieu Desnoyers
>> mathieu.desnoyers@efficios.com wrote:
>>
>> > ----- On Feb 18, 2019, at 7:26 AM, Greg Kroah-Hartman gregkh@linuxfoundation.org
>> > wrote:
>> >
>> >> On Wed, Feb 06, 2019 at 01:41:15PM +0900, Masami Hiramatsu wrote:
>> >>> On Tue, 5 Feb 2019 15:06:10 +0000
>> >>> Kees Cook <keescook@chromium.org> wrote:
>> >>>
>> >>> > On Mon, Feb 4, 2019 at 7:15 PM Mathieu Desnoyers
>> >>> > <mathieu.desnoyers@efficios.com> wrote:
>> >>> > >
>> >>> > > Hi,
>> >>> > >
>> >>> > > I notice this commit as a possible culprit of the illegal instructions my lttng
>> >>> > > users are noticing on arm32 when using kprobes on a v4.19.13 Linux kernel
>> >>> > > in a Yocto environment [1]. They were able to reproduce the issue with perf
>> >>> > > as well.
>> >>> > >
>> >>> > > commit e46daee53bb50bde38805f1823a182979724c229
>> >>> > > Author: Kees Cook <keescook@chromium.org>
>> >>> > > Date: Tue Oct 30 22:12:56 2018 +0100
>> >>> > >
>> >>> > > ARM: 8806/1: kprobes: Fix false positive with FORTIFY_SOURCE
>> >>> > >
>> >>> > > I *think* the intent there was to do
>> >>> > >
>> >>> > > - memcpy(code, &optprobe_template_entry,
>> >>> > > + memcpy(code, (unsigned long *)&optprobe_template_entry,
>> >>> > >
>> >>> > > But if you look at the commit, the "&" seems to have been stripped away,
>> >>> > > which happens to change the behavior significantly.
>> >>> >
>> >>> > Yeah, this was a typo on my part. :(
>> >>>
>> >>> Ah, I thought it had been fixed as same as x86.
>> >>> On x86, all optprobe_template_* are defined as kprobe_opcode_t [],
>> >>> but on arm, it still be kprobe_opcode_t.
>> >>>
>> >>> Hmm, but I think we should use kprobe_opcode_t [] or char[] as asm/sections.h
>> >>> does.
>> >>> OK, I'll prepare for the change.
>> >>
>> >> Did this ever get fixed in Linus's tree? If so, what is the git commit
>> >> id, I can't seem to find anything...
>> >
>> > It seems to still be in the arm patch tracking system:
>> >
>> > https://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=8834/1
>> >
>> > If I understand its status correctly, it is applied to the arm tree, but
>> > perhaps it has not been pulled by Linus yet ? The code is still broken
>> > in Linus' master.
>> >
>> > It would be important to get this arm kprobes fix upstream before 5.0
>> > final.
>> >
>> > Thanks,
>> >
>> > Mathieu
>> >
>> >
>> > --
>> > Mathieu Desnoyers
>> > EfficiOS Inc.
>> > http://www.efficios.com
>>
>> --
>> Mathieu Desnoyers
>> EfficiOS Inc.
>> http://www.efficios.com
>>
>
> --
> RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
> FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up
> According to speedtest.net: 11.9Mbps down 500kbps up
--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: BUG: optimized kprobes illegal instructions in v4.19 stable kernels
2019-02-22 0:17 ` Mathieu Desnoyers
@ 2019-02-22 6:25 ` Greg Kroah-Hartman
2019-02-22 8:29 ` Greg Kroah-Hartman
0 siblings, 1 reply; 13+ messages in thread
From: Greg Kroah-Hartman @ 2019-02-22 6:25 UTC (permalink / raw)
To: Mathieu Desnoyers
Cc: Russell King, ARM Linux, Arnd Bergmann, Linus Torvalds,
Masami Hiramatsu, Kees Cook, William Cohen, stable, Laura Abbott,
linux-kernel, lttng, Thomas Gleixner
On Thu, Feb 21, 2019 at 07:17:11PM -0500, Mathieu Desnoyers wrote:
> ----- On Feb 21, 2019, at 7:10 PM, Russell King, ARM Linux linux@armlinux.org.uk wrote:
>
> > On Thu, Feb 21, 2019 at 03:02:57PM -0500, Mathieu Desnoyers wrote:
> >> Hi Arnd, Russell, Linus,
> >>
> >> Can we ensure the arm32 kprobes fix I submitted gets upstream before 5.0 final ?
> >> It takes care of an illegal instruction issue with optimized kprobes on arm32.
> >>
> >> Here is the current state of default kprobes configuration on arm32:
> >> using them will trigger illegal instruction OOPS on v5.0-rc7, 4.19.24,
> >> v4.14.102.
> >>
> >> My fix is in "accepted" state in the arm patch tracking system:
> >>
> >> https://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=8834/1
> >>
> >> Should I send it directly to Linus as well ?
> >
> > Accepted means it's in my tree pending to be sent to Linus. It should
> > now be in mainline. Have you checked?
>
> Hrm, why did I not see it earlier today... it's embarrassing.
>
> It's there indeed, all is good!
>
> Greg, you should be able to pick it into the stable kernels now.
What is the git commit id of it?
thanks,
greg k-h
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: BUG: optimized kprobes illegal instructions in v4.19 stable kernels
2019-02-22 6:25 ` Greg Kroah-Hartman
@ 2019-02-22 8:29 ` Greg Kroah-Hartman
2019-02-22 20:18 ` Mathieu Desnoyers
0 siblings, 1 reply; 13+ messages in thread
From: Greg Kroah-Hartman @ 2019-02-22 8:29 UTC (permalink / raw)
To: Mathieu Desnoyers
Cc: Russell King, ARM Linux, Arnd Bergmann, Linus Torvalds,
Masami Hiramatsu, Kees Cook, William Cohen, stable, Laura Abbott,
linux-kernel, lttng, Thomas Gleixner
On Fri, Feb 22, 2019 at 07:25:50AM +0100, Greg Kroah-Hartman wrote:
> On Thu, Feb 21, 2019 at 07:17:11PM -0500, Mathieu Desnoyers wrote:
> > ----- On Feb 21, 2019, at 7:10 PM, Russell King, ARM Linux linux@armlinux.org.uk wrote:
> >
> > > On Thu, Feb 21, 2019 at 03:02:57PM -0500, Mathieu Desnoyers wrote:
> > >> Hi Arnd, Russell, Linus,
> > >>
> > >> Can we ensure the arm32 kprobes fix I submitted gets upstream before 5.0 final ?
> > >> It takes care of an illegal instruction issue with optimized kprobes on arm32.
> > >>
> > >> Here is the current state of default kprobes configuration on arm32:
> > >> using them will trigger illegal instruction OOPS on v5.0-rc7, 4.19.24,
> > >> v4.14.102.
> > >>
> > >> My fix is in "accepted" state in the arm patch tracking system:
> > >>
> > >> https://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=8834/1
> > >>
> > >> Should I send it directly to Linus as well ?
> > >
> > > Accepted means it's in my tree pending to be sent to Linus. It should
> > > now be in mainline. Have you checked?
> >
> > Hrm, why did I not see it earlier today... it's embarrassing.
> >
> > It's there indeed, all is good!
> >
> > Greg, you should be able to pick it into the stable kernels now.
>
> What is the git commit id of it?
Oh nevermind, I see it. I'll queue it up for the next round of kernel
releases after this one.
thanks,
greg k-h
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: BUG: optimized kprobes illegal instructions in v4.19 stable kernels
2019-02-22 8:29 ` Greg Kroah-Hartman
@ 2019-02-22 20:18 ` Mathieu Desnoyers
0 siblings, 0 replies; 13+ messages in thread
From: Mathieu Desnoyers @ 2019-02-22 20:18 UTC (permalink / raw)
To: Greg Kroah-Hartman
Cc: Russell King, ARM Linux, Arnd Bergmann, Linus Torvalds,
Masami Hiramatsu, Kees Cook, William Cohen, stable, Laura Abbott,
linux-kernel, lttng, Thomas Gleixner
----- On Feb 22, 2019, at 3:29 AM, Greg Kroah-Hartman gregkh@linuxfoundation.org wrote:
> On Fri, Feb 22, 2019 at 07:25:50AM +0100, Greg Kroah-Hartman wrote:
>> On Thu, Feb 21, 2019 at 07:17:11PM -0500, Mathieu Desnoyers wrote:
>> > ----- On Feb 21, 2019, at 7:10 PM, Russell King, ARM Linux linux@armlinux.org.uk
>> > wrote:
>> >
>> > > On Thu, Feb 21, 2019 at 03:02:57PM -0500, Mathieu Desnoyers wrote:
>> > >> Hi Arnd, Russell, Linus,
>> > >>
>> > >> Can we ensure the arm32 kprobes fix I submitted gets upstream before 5.0 final ?
>> > >> It takes care of an illegal instruction issue with optimized kprobes on arm32.
>> > >>
>> > >> Here is the current state of default kprobes configuration on arm32:
>> > >> using them will trigger illegal instruction OOPS on v5.0-rc7, 4.19.24,
>> > >> v4.14.102.
>> > >>
>> > >> My fix is in "accepted" state in the arm patch tracking system:
>> > >>
>> > >> https://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=8834/1
>> > >>
>> > >> Should I send it directly to Linus as well ?
>> > >
>> > > Accepted means it's in my tree pending to be sent to Linus. It should
>> > > now be in mainline. Have you checked?
>> >
>> > Hrm, why did I not see it earlier today... it's embarrassing.
>> >
>> > It's there indeed, all is good!
>> >
>> > Greg, you should be able to pick it into the stable kernels now.
>>
>> What is the git commit id of it?
>
> Oh nevermind, I see it. I'll queue it up for the next round of kernel
> releases after this one.
Sorry about late reply, it's indeed
commit 0ac569bf6a79 ("ARM: 8834/1: Fix: kprobes: optimized kprobes illegal instruction")
upstream.
Thanks!
Mathieu
--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com
^ permalink raw reply [flat|nested] 13+ messages in thread
end of thread, other threads:[~2019-02-22 20:18 UTC | newest]
Thread overview: 13+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-02-04 19:15 BUG: optimized kprobes illegal instructions in v4.19 stable kernels Mathieu Desnoyers
2019-02-05 15:06 ` Kees Cook
2019-02-06 4:41 ` Masami Hiramatsu
2019-02-18 12:26 ` Greg KH
2019-02-18 14:11 ` Masami Hiramatsu
2019-02-18 14:55 ` Mathieu Desnoyers
2019-02-21 20:02 ` Mathieu Desnoyers
2019-02-22 0:10 ` Russell King - ARM Linux admin
2019-02-22 0:17 ` Mathieu Desnoyers
2019-02-22 6:25 ` Greg Kroah-Hartman
2019-02-22 8:29 ` Greg Kroah-Hartman
2019-02-22 20:18 ` Mathieu Desnoyers
2019-02-06 11:48 ` David Laight
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