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Re: [PATCH 00/12] x86/CET: The last 12 patches to enable Intel CET
On Fri, Jul 27, 2018 at 10:52 AM, Florian Weimer <fweimer@redhat.com> wrote:
> On 07/27/2018 07:50 PM, H.J. Lu wrote:
>>
>> On Fri, Jul 27, 2018 at 10:13 AM, H.J. Lu <hjl.tools@gmail.com> wrote:
>>>
>>> On Fri, Jul 27, 2018 at 9:49 AM, Florian Weimer <fweimer@redhat.com>
>>> wrote:
>>>>
>>>> On 07/27/2018 06:47 PM, H.J. Lu wrote:
>>>>>
>>>>>
>>>>> On Fri, Jul 27, 2018 at 9:44 AM, Florian Weimer <fweimer@redhat.com>
>>>>> wrote:
>>>>>>
>>>>>>
>>>>>> On 07/27/2018 06:37 PM, H.J. Lu wrote:
>>>>>>
>>>>>>>> We load datasz and then check for having encountered the last note.
>>>>>>>> I'm
>>>>>>>> checking a fix.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> How can I reproduce it?
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> Perhaps it is only visible with an explicit invocation of the dynamic
>>>>>> linker?
>>>>>>
>>>>>> I saw it while building GCC on Fedora rawhide. I've pushed my latest
>>>>>> changes (commit a4a5659439698554d18b9f1ef56cbd86591e217b) to the
>>>>>> distribution Git, even though they do not build. The valgrind check
>>>>>> at
>>>>>> the
>>>>>> end of the build fails.
>>>>>
>>>>>
>>>>>
>>>>> What is the command line to reproduce it with glibc build configured
>>>>> with --enable-cet?
>>>>
>>>>
>>>>
>>>> This command is run inside the build directory:
>>>>
>>>> elf/ld.so --library-path .:elf:nptl:dlfcn /usr/bin/valgrind
>>>> --vgdb-error=1
>>>> --track-origins=yes --error-exitcode=1 elf/ld.so --library-path
>>>> .:elf:nptl:dlfcn /usr/bin/true
>>>>
>>>
>>> [hjl@gnu-cet-2 build-x86_64-linux]$ elf/ld.so --library-path
>>> .:elf:nptl:dlfcn /usr/bin/valgrind --vgdb-error=1 --track-origins=yes
>>> --error-exitcode=1 elf/ld.so --library-path .:elf:nptl:dlfcn
>>> /usr/bin/true
>>>
>>
>> Your note may be different. Mine has
>>
>> [hjl@gnu-cet-1 build-x86_64-linux]$ readelf -n elf/ld.so
>>
>> Displaying notes found in: .note.gnu.build-id
>> Owner Data size Description
>> GNU 0x00000014 NT_GNU_BUILD_ID (unique build ID
>> bitstring)
>> Build ID: 47063ae06339e7226b68aa983cd3225f2dfa1ee2
>>
>> Displaying notes found in: .note.gnu.property
>> Owner Data size Description
>> GNU 0x00000010 NT_GNU_PROPERTY_TYPE_0
>> Properties: x86 feature: IBT, SHSTK
>> [hjl@gnu-cet-1 build-x86_64-linux]$
>>
>> Can you send me your elf/ld.so?
>
>
> The note for /bin/true causes the problem. I'm attaching it.
>
Yes, I can reproduce it. Let me take a look.
--
H.J.