From: Florian Weimer <fweimer@redhat.com>
To: "H.J. Lu" <hjl.tools@gmail.com>
Cc: Carlos O'Donell <carlos@redhat.com>,
GNU C Library <libc-alpha@sourceware.org>
Subject: Re: [PATCH 0/2] nptl: Update struct pthread_unwind_buf
Date: Fri, 9 Feb 2018 15:33:52 +0100 [thread overview]
Message-ID: <a62f1819-12e9-9e11-51bf-96ed0c7fc2d5@redhat.com> (raw)
In-Reply-To: <CAMe9rOoW+h_Zkr5qy5T_Z2mt_gvipFYV_UYtCxzCtKvtb-4N2A@mail.gmail.com>
On 02/09/2018 03:13 PM, H.J. Lu wrote:
> I built glibc master with gcc-8.0.1 -mcet -fcf-protection. Some object
> files do get CET marker as expected. But static executable isn't:
I said static libraries. If I compile this code (based on the example
from the manual page) on Fedora rawhide:
#include <pthread.h>
#include <stdio.h>
static int done = 0;
static int cleanup_pop_arg = 0;
static int cnt = 0;
static void
cleanup_handler(void *arg)
{
printf("Called clean-up handler\n");
cnt = 0;
}
void *
thread_start(void *arg)
{
time_t start, curr;
printf("New thread started\n");
pthread_cleanup_push(cleanup_handler, NULL);
curr = start = time(NULL);
while (!done) {
pthread_testcancel(); /* A cancellation point */
if (curr < time(NULL)) {
curr = time(NULL);
printf("cnt = %d\n", cnt); /* A cancellation point */
cnt++;
}
}
pthread_cleanup_pop(cleanup_pop_arg);
return NULL;
}
the small jump buffer is used:
0000000000000030 <thread_start>:
30: f3 0f 1e fa endbr64
34: 53 push %rbx
35: bf 00 00 00 00 mov $0x0,%edi
36: R_X86_64_32 .rodata.str1.1+0x18
3a: 48 83 ec 70 sub $0x70,%rsp
3e: e8 00 00 00 00 callq 43 <thread_start+0x13>
3f: R_X86_64_PC32 puts-0x4
43: 31 f6 xor %esi,%esi
45: 48 89 e7 mov %rsp,%rdi
48: e8 00 00 00 00 callq 4d <thread_start+0x1d>
49: R_X86_64_PC32 __sigsetjmp-0x4
4d: f3 0f 1e fa endbr64
51: 85 c0 test %eax,%eax
53: 75 51 jne a6 <thread_start+0x76>
55: 48 89 e7 mov %rsp,%rdi
58: e8 00 00 00 00 callq 5d <thread_start+0x2d>
59: R_X86_64_PC32 __pthread_register_cancel-0x4
And it looks to me that readelf says the object file is compatible with CET:
Displaying notes found in: .note.gnu.property
Owner Data size Description
GNU 0x00000010 NT_GNU_PROPERTY_TYPE_0
Properties: x86 feature: IBT, SHSTK
Thanks,
Florian
next prev parent reply other threads:[~2018-02-09 14:31 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-01 20:57 [PATCH 0/2] nptl: Update struct pthread_unwind_buf H.J. Lu
2018-02-01 20:57 ` [PATCH 1/2] Revert "Revert Intel CET changes to __jmp_buf_tag (Bug 22743)" H.J. Lu
2018-02-01 20:57 ` [PATCH 2/2] nptl: Update struct pthread_unwind_buf [BZ #22743] H.J. Lu
2018-02-08 9:25 ` [PATCH 0/2] nptl: Update struct pthread_unwind_buf Carlos O'Donell
2018-02-08 11:55 ` Florian Weimer
2018-02-09 6:29 ` Carlos O'Donell
2018-02-09 10:48 ` Florian Weimer
2018-02-09 11:13 ` H.J. Lu
2018-02-09 12:11 ` Florian Weimer
2018-02-09 12:34 ` H.J. Lu
2018-02-09 14:13 ` H.J. Lu
2018-02-09 14:33 ` Florian Weimer [this message]
2018-02-09 15:24 ` H.J. Lu
2018-02-24 5:46 ` Carlos O'Donell
2018-02-24 15:19 ` H.J. Lu
2018-02-24 15:46 ` Florian Weimer
2018-02-25 2:04 ` H.J. Lu
2018-02-25 9:26 ` Florian Weimer
2018-02-25 11:37 ` H.J. Lu
2018-02-25 11:59 ` Florian Weimer
2018-02-25 12:53 ` H.J. Lu
2018-02-25 12:55 ` H.J. Lu
2018-02-25 12:58 ` Florian Weimer
2018-02-25 13:23 ` H.J. Lu
2018-02-25 13:31 ` Florian Weimer
2018-02-25 13:36 ` H.J. Lu
2018-02-25 13:49 ` H.J. Lu
2018-02-25 13:49 ` Florian Weimer
2018-02-25 14:00 ` H.J. Lu
2018-02-25 14:13 ` Florian Weimer
2018-02-26 3:55 ` H.J. Lu
2018-02-28 23:23 ` Carlos O'Donell
2018-03-07 11:56 ` H.J. Lu
2018-03-07 17:34 ` Carlos O'Donell
2018-03-07 19:47 ` H.J. Lu
2018-03-07 20:14 ` H.J. Lu
2018-03-07 22:06 ` H.J. Lu
2018-03-08 12:24 ` Tsimbalist, Igor V
2018-03-08 12:48 ` H.J. Lu
2018-03-09 0:47 ` Carlos O'Donell
2018-03-09 5:23 ` H.J. Lu
2018-03-15 4:20 ` Carlos O'Donell
2018-02-24 6:41 ` Carlos O'Donell
2018-02-08 13:27 ` H.J. Lu
2018-02-09 6:40 ` Carlos O'Donell
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