This is the mail archive of the
glibc-bugs@sourceware.org
mailing list for the glibc project.
[Bug libc/12597] New: SSE4 strncmp failure
- From: "hjl.tools at gmail dot com" <sourceware-bugzilla at sourceware dot org>
- To: glibc-bugs at sources dot redhat dot com
- Date: Mon, 21 Mar 2011 04:42:39 +0000
- Subject: [Bug libc/12597] New: SSE4 strncmp failure
- Auto-submitted: auto-generated
http://sourceware.org/bugzilla/show_bug.cgi?id=12597
Summary: SSE4 strncmp failure
Product: glibc
Version: 2.13
Status: NEW
Severity: normal
Priority: P2
Component: libc
AssignedTo: drepper.fsp@gmail.com
ReportedBy: hjl.tools@gmail.com
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)
--
Configure bugmail: http://sourceware.org/bugzilla/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are on the CC list for the bug.