kosaki

 44.43%  ebizzy  ebizzy             [.] memcpy                                                               
 30.67%  ebizzy  [kernel.kallsyms]  [k] default_send_IPI_mask_allbutself_phys                              a
 12.52%  ebizzy  [kernel.kallsyms]  [k] _raw_spin_unlock_irqrestore                                        a
  6.11%  ebizzy  [kernel.kallsyms]  [k] smp_call_function_many                                             a
  0.87%  ebizzy  [kernel.kallsyms]  [k] __do_softirq                                                       a
  0.57%  ebizzy  [kernel.kallsyms]  [k] lazyfree_range                                                     a
  0.52%  ebizzy  [kernel.kallsyms]  [k] deactivate_page                                                    a
  0.45%  ebizzy  ebizzy             [.] write_pattern                                                      a
  0.36%  ebizzy  [kernel.kallsyms]  [k] release_pages                                                      a
  0.28%  ebizzy  [kernel.kallsyms]  [k] de

kosaki

$ memstomp -d  ./employee
memstomp: 0.1.4 successfully initialized for process employee (pid 30842).
 
 
strcat(dest=0x7fff82e79285, src=0x7fff82e79289, bytes=21) overlap for employee(30842)
        ??:0    strcpy()
        ??:0    strcpy()
        ??:0    strcat()
        employee.c:26   main()
        ??:0    __libc_start_main()

kosaki

MEMSTOMP(1)                            General Commands Manual                           MEMSTOMP(1)

NAME
       memstomp - detect function calls with overlapping memory regions

SYNOPSIS
       memstomp [-dk] application [argument...]

       memstomp -h

kosaki

#include <stdio.h>
#include <string.h>

#define BUFSIZE 80

int main(int argc, char *argv[]) {
  char employee[BUFSIZE] = "John,Doe,john@example.com";
  char name[BUFSIZE] = {0};
  char surname[BUFSIZE] = {0};
  char *email;

kosaki

Binary compatibility report for the libruby library  between unspecified and
unspecified versions on x86_64

Test Info

-------------------------------------------------------------------------------

Library Name  libruby
 Version #1   unspecified
 Version #2   unspecified

kosaki

commit d84ba638e4ba3c40023ff997aa5e8d3ed002af36
Author: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Date:   Tue Aug 24 16:05:48 2010 +0000

    tcp: select(writefds) don't hang up when a peer close connection
    
    This issue come from ruby language community. Below test program
    hang up when only run on Linux.
    
        % uname -mrsv

kosaki

% make         
cc -D_FORTIFY_SOURCE=2 -Wall -g -O2    memcpy_test.c memcpy_chk.c   -o memcpy_test
In function ‘my_memcpy’,
    inlined from ‘main’ at memcpy_test.c:29:
memcpy_test.c:17: 警告: call to ‘my_memcpy_warn’ declared with attribute warning: my warning

% ./memcpy_test 
my buffer overflow detection
[1]    27873 abort (core dumped)  ./memcpy_test

kosaki

__fortify_function wchar_t *
__NTH (wcpcpy (wchar_t *__restrict __dest, const wchar_t *__restrict __src))
{
  if (__bos (__dest) != (size_t) -1)
    return __wcpcpy_chk (__dest, __src, __bos (__dest) / sizeof (wchar_t));
  return __wcpcpy_alias (__dest, __src);
}

kosaki

#include <string.h>
#include <stdio.h>

void* xmalloc(size_t s) __attribute__ ((alloc_size(1)));

int main(void)
{
  char *str = "12345";
	char *buf = xmalloc(5);

kosaki

#include <string.h>
#include <stdio.h>

void* xmalloc(size_t s);

int main(void)
{
  char *str = "12345";
	char *buf = xmalloc(5);