查看是否允许的core dump文件大小。如果只是临时需要用到可以使用命令ulimit -c unlimited临时打开则发生段错误时会在当前目录下产生core文件。若是需要配置一直生效并指定core文件生成路径和一些其他的信息可以用如下命令在etc/sysctl。
  conf目录中添加kernel。core_pattern=/var/coredump/%t-%e-%p-%c。corekernel。core_uses_pid=0#sysctl -p1、栈溢出在ubuntu上默认的栈空间大小为8192kb应用程序的栈超过这个值就会发生段错误可以通过命令ulimit -s来查看设置的栈的大小。
  ubuntu14。04 32位 执行如下程序#include<stdio。h>#include<unistd。h>#include<string。h>voidcall_fault(void){chararray[9*1024*1024];memset(array,0,sizeof(array));}voidcall_test(void){inta;a=1;call_fault();}intmain(){call_test();return0;}root@zhuzhu:test_work#gcc -g -Wall stack_out。
  croot@zhuzhu:test_work# 。/a。outSegmentation fault (core dumped)执行过后会在当前目录下生成core文件root@zhuzhu:test_work# gdb 。/a。out core ----->调试开始GNU gdb (Ubuntu 7。
  7。1-0ubuntu5~14。04。2) 7。7。1Copyright (C) 2014 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 "i686-linux-gnu"。Type "show configuration" for configuration details。
  For bug reporting instructions, please see:<http://www。gnu。org/software/gdb/bugs/>Find the GDB manual and other documentation resources online at:<http://www。
  gnu。org/software/gdb/documentation/>For help, type "help"。Type "apropos word" to search for commands related to "word"。
  Reading symbols from 。/a。out。done。warning: exec file is newer than core file。[New LWP 12155]Core was generated by `。/a。out‘。
  Program terminated with signal SIGSEGV, Segmentation fault。#0 0x080484bc in __libc_csu_init ()---->从上面的信息来看并没有给出什么有效信息(gdb)bt fullPython Exception <class ‘gdb。
  MemoryError‘> Cannot access memory at address 0xbf359d20:#0 0x080484bc in __libc_csu_init ()No symbol table info available。
  Cannot access memory at address 0xbf359d20 ---->从这里看栈帧好像被破坏了给出的有效信息是没有权限访问地址0xbf359d20首先来查看一下程序内存地址映射(gdb)(gdb) info proc mappings ---->栈已经被破坏无法得到stack信息Mapped address spaces:Start Addr End Addr Size Offset objfile0x8048000 0x8049000 0x1000 0x0 /root/work/test_work/a。
  out0x8049000 0x804a000 0x1000 0x0 /root/work/test_work/a。out0x804a000 0x804b000 0x1000 0x1000 /root/work/test_work/a。out0xb757d000 0xb7725000 0x1a8000 0x0 /lib/i386-linux-gnu/libc-2。
  19。so0xb7725000 0xb7727000 0x2000 0x1a8000 /lib/i386-linux-gnu/libc-2。19。so0xb7727000 0xb7728000 0x1000 0x1aa000 /lib/i386-linux-gnu/libc-2。
  19。so0xb7747000 0xb7767000 0x20000 0x0 /lib/i386-linux-gnu/ld-2。19。so0xb7767000 0xb7768000 0x1000 0x1f000 /lib/i386-linux-gnu/ld-2。
  19。so(gdb)(gdb) i regeax 0x8048610134514192ecx 0x8048615134514197edx 0x1420ebx 0xb7727000-1217236992esp 0xbf359d100xbf359d10 ----->查看栈指针指向的位置ebp 0xbfc59d380xbfc59d38esi 0x00edi 0x00eip 0x80484bc0x80484bc <__libc_csu_init+12>eflags 0x10246[ PF ZF IF RF ]cs 0x73115ss 0x7b123ds 0x7b123es 0x7b123fs 0x00gs 0x3351退出gdb后执行gdb 。
  /a。out(gdb) quit ---->退出gdbroot@zhuzhu:test_work# gdb 。/a。outGNU gdb (Ubuntu 7。7。1-0ubuntu5~14。04。2) 7。7。1Copyright (C) 2014 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 "i686-linux-gnu"。
  Type "show configuration" for configuration details。For bug reporting instructions, please see:<http://www。gnu。org/software/gdb/bugs/>Find the GDB manual and other documentation resources online at:<http://www。
  gnu。org/software/gdb/documentation/>For help, type "help"。Type "apropos word" to search for commands related to "word"。
  Reading symbols from 。/a。out。done。(gdb) esp 0xbf359d100xbf359d10Undefined command: "esp"。 Try "help"。(gdb) startTemporary breakpoint 1 at 0x80484a2: file stack_out。
  c, line 22。Starting program: /root/work/test_work/a。out‘Temporary breakpoint 1, main () at stack_out。c:2222 call_test();(gdb) info proc mappingsprocess 12403Mapped address spaces:Start Addr End Addr Size Offset objfile0x8048000 0x8049000 0x1000 0x0 /root/work/test_work/a。
  out0x8049000 0x804a000 0x1000 0x0 /root/work/test_work/a。out0x804a000 0x804b000 0x1000 0x1000 /root/work/test_work/a。out0xb7e13000 0xb7e14000 0x1000 0x00xb7e14000 0xb7fbc000 0x1a8000 0x0 /lib/i386-linux-gnu/libc-2。
  19。so0xb7fbc000 0xb7fbe000 0x2000 0x1a8000 /lib/i386-linux-gnu/libc-2。19。so0xb7fbe000 0xb7fbf000 0x1000 0x1aa000 /lib/i386-linux-gnu/libc-2。
  19。so0xb7fbf000 0xb7fc2000 0x3000 0x00xb7fd8000 0xb7fda000 0x2000 0x00xb7fda000 0xb7fdc000 0x2000 0x0 [vvar]0xb7fdc000 0xb7fde000 0x2000 0x0 [vdso]0xb7fde000 0xb7ffe000 0x20000 0x0 /lib/i386-linux-gnu/ld-2。
  19。so0xb7ffe000 0xb7fff000 0x1000 0x1f000 /lib/i386-linux-gnu/ld-2。19。so0xb7fff000 0xb8000000 0x1000 0x20000 /lib/i386-linux-gnu/ld-2。
  19。so0xbffdf000 0xc0000000 0x21000 0x0 [stack] ----->可以看到栈的范围(gdb)有上面的调试信息可以知道但发生段错误是sp指针是指向0xbf359d10已经超出了栈的下限范围。本文出自 “12128867” 博客，请务必保留此出处http://12138867。
  blog。51cto。com/12128867/1914119GDB调试之二栈溢出。