[PATCH 00/12] x86/CET: The last 12 patches to enable Intel CET

[Florian Weimer]

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.

Thanks,
Florian
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