Program received signal SIGSEGV, Segmentation fault.

 

Program received signal SIGSEGV, Segmentation fault.

wo們知道SIGSEGV預設handler的動作是列印”段錯誤"的出錯資訊，併產生Core檔案，

lihacker@lihacker-laptop:~$ ulimit -c
0
lihacker@lihacker-laptop:~$ ulimit -c 1000
lihacker@lihacker-laptop:~$ ulimit -c
1000
lihacker@lihacker-laptop:~$
 

解除禁止產生core檔案 即可看到產生的core .  此時並沒有產生core檔案，接下來使用ulimit -c設定core檔案大小為無限制

lihacker@lihacker-laptop:~$ ulimit -c
0
lihacker@lihacker-laptop:~$ ulimit -c unlimited
lihacker@lihacker-laptop:~$ ./clone
Segmentation fault (core dumped)

下一步：lihacker@lihacker-laptop:~$ gdb ./clone core

lihacker@lihacker-laptop:~$ valgrind --tool=memcheck --leak-check=yes --show-reachable=yes -v --num-callers=20 --track-fds=yes ./clone_thread

 

==22731== Invalid write of size 4
==22731==    at 0x412145B: clone (in /lib/tls/i686/cmov/libc-2.9.so)
==22731==    by 0x4053774: (below main) (in /lib/tls/i686/cmov/libc-2.9.so)
==22731==  Address 0x41a1010 is not stack'd, malloc'd or (recently) free'd
==22731==
==22731== Invalid write of size 4
==22731==    at 0x4121462: clone (in /lib/tls/i686/cmov/libc-2.9.so)
==22731==    by 0x4053774: (below main) (in /lib/tls/i686/cmov/libc-2.9.so)
==22731==  Address 0x41a100c is not stack'd, malloc'd or (recently) free'd
==22731==
==22731== Invalid write of size 4
==22731==    at 0x4121465: clone (in /lib/tls/i686/cmov/libc-2.9.so)
==22731==    by 0x4053774: (below main) (in /lib/tls/i686/cmov/libc-2.9.so)
==22731==  Address 0x41a1008 is not stack'd, malloc'd or (recently) free'd
==22731==
==22731== Invalid write of size 4
==22731==    at 0x4121484: clone (in /lib/tls/i686/cmov/libc-2.9.so)
==22731==    by 0x4053774: (below main) (in /lib/tls/i686/cmov/libc-2.9.so)
==22731==  Address 0x41a1004 is not stack'd, malloc'd or (recently) free'd