forked from rpms/glibc
55 lines
1.7 KiB
Plaintext
55 lines
1.7 KiB
Plaintext
|
PURPOSE of /tools/glibc/Regression/bz689471-SSE4-strncmp-failure
|
||
|
|
Description: Test for bz689471 (SSE4 strncmp failure)
|
||
|
|
Author: Miroslav Franc <mfranc@redhat.com>
|
||
|
|
Bug summary: SSE4 strncmp failure
|
||
|
|
Bugzilla link: https://bugzilla.redhat.com/show_bug.cgi?id=689471
|
||
|
|
|
||
|
|
Description:
|
||
|
|
|
||
|
|
H.J. Lu 2011-03-21 05:42:34 CET
|
||
|
|
On Intel Core i7, I got
|
||
|
|
|
||
|
|
[hjl@gnu-6 997]$ cat saved.c
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <string.h>
|
||
|
|
#include <sys/mman.h>
|
||
|
|
|
||
|
|
int main()
|
||
|
|
{
|
||
|
|
char *buf, *buf2;
|
||
|
|
|
||
|
|
buf = (char*)mmap((void*)0x100000000, 0x2000 * 2,
|
||
|
|
PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
|
||
|
|
buf = mmap((char *)buf, 0x2000, PROT_READ | PROT_WRITE,
|
||
|
|
MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
|
||
|
|
memset(buf, 'a', 0x2000);
|
||
|
|
buf[0x1fff] = 0;
|
||
|
|
buf2 = strdup(buf);
|
||
|
|
if (strncmp (buf + 3994, buf2 + 2635, 6241) >= 0)
|
||
|
|
abort ();
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
[hjl@gnu-6 997]$ gcc saved.c
|
||
|
|
[hjl@gnu-6 997]$ ./a.out
|
||
|
|
Segmentation fault
|
||
|
|
[hjl@gnu-6 997]$ gdb a.out
|
||
|
|
GNU gdb (GDB) 7.2.50.20110312-cvs
|
||
|
|
Copyright (C) 2011 Free Software Foundation, Inc.
|
||
|
|
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
|
||
|
|
This is free software: you are free to change and redistribute it.
|
||
|
|
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
|
||
|
|
and "show warranty" for details.
|
||
|
|
This GDB was configured as "x86_64-unknown-linux-gnu".
|
||
|
|
For bug reporting instructions, please see:
|
||
|
|
<http://www.gnu.org/software/gdb/bugs/>...
|
||
|
|
Reading symbols from /export/home/hjl/bugs/libc/997/a.out...(no debugging
|
||
|
|
symbols found)...done.
|
||
|
|
(gdb) r
|
||
|
|
Starting program: /export/home/hjl/bugs/libc/997/a.out
|
||
|
|
|
||
|
|
Program received signal SIGSEGV, Segmentation fault.
|
||
|
|
0x0000003f7d3214a0 in __strncmp_sse42 () from /lib64/libc.so.6
|
||
|
|
(gdb)
|