On 11/28/2017 09:02 PM, Josef Bacik wrote:
> On Tue, Nov 28, 2017 at 11:58:41AM -0700, Jonathan Corbet wrote:
>> On Wed, 22 Nov 2017 16:23:30 -0500
>> Josef Bacik <[email protected]> wrote:
>>> From: Josef Bacik <[email protected]>
>>>
>>> Using BPF we can override kprob'ed functions and return arbitrary
>>> values. Obviously this can be a bit unsafe, so make this feature opt-in
>>> for functions. Simply tag a function with KPROBE_ERROR_INJECT_SYMBOL in
>>> order to give BPF access to that function for error injection purposes.
>>>
>>> Signed-off-by: Josef Bacik <[email protected]>
>>> Acked-by: Ingo Molnar <[email protected]>
>>> ---
>>> arch/x86/include/asm/asm.h | 6 ++
>>> include/asm-generic/vmlinux.lds.h | 10 +++
>>> include/linux/bpf.h | 11 +++
>>> include/linux/kprobes.h | 1 +
>>> include/linux/module.h | 5 ++
>>> kernel/kprobes.c | 163 ++++++++++++++++++++++++++++++++++++++
>>> kernel/module.c | 6 +-
>>> 7 files changed, 201 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h
>>> index b0dc91f4bedc..340f4cc43255 100644
>>> --- a/arch/x86/include/asm/asm.h
>>> +++ b/arch/x86/include/asm/asm.h
>>> @@ -85,6 +85,12 @@
>>> _ASM_PTR (entry); \
>>> .popsection
>>>
>>> +# define _ASM_KPROBE_ERROR_INJECT(entry) \
>>> + .pushsection "_kprobe_error_inject_list","aw" ; \
>>> + _ASM_ALIGN ; \
>>> + _ASM_PTR (entry); \
>>> + .popseciton
>>
>> So this stuff is not my area of greatest expertise, but I do have to wonder
>> how ".popseciton" can work ... ?
>
> Well fuck, do you want me to send a increment Daniel/Alexei or resend this patch
> fixed? Thanks,
Sorry for late reply, please rebase + respin the whole series with
this fixed. There were also few typos in the cover letter / commit
messages that would be good to get fixed along the way.
Also, could you debug why this wasn't caught at compile/runtime during
testing?
Thanks a lot,
Daniel
From 1585341458720838391@xxx Tue Nov 28 20:03:51 +0000 2017
X-GM-THRID: 1584803075397522780
X-Gmail-Labels: Inbox,Category Forums,HistoricalUnread