Re: [dev] skvm bug and question

On 02/09/2010 09:59 PM, stateless wrote:
> Could you run it through valgrind and attach the output? You can also
> run it under gdb and see where it fails.
Sure. Full-length valgrin and gdb outputs follow.

---- Begin Valgrind/gdb output ----

[jonas_AT_jarchy ~]$ valgrind skvm --help
==8951== Command: skvm --help
==8951==
==8951== Invalid read of size 1
==8951== at 0x4024B32: strncmp (in
/usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==8951== by 0x422C587: _getopt_internal_r (in /lib/libc-2.11.1.so)
==8951== by 0x422D42D: _getopt_internal (in /lib/libc-2.11.1.so)
==8951== by 0x422D678: getopt_long (in /lib/libc-2.11.1.so)
==8951== by 0x804A5BB: ??? (in /usr/bin/skvm)
==8951== by 0x418FB85: (below main) (in /lib/libc-2.11.1.so)
==8951== Address 0xffffffff is not stack'd, malloc'd or (recently) free'd
==8951==
==8951==
==8951== Process terminating with default action of signal 11 (SIGSEGV)
==8951== Access not within mapped region at address 0xFFFFFFFF
==8951== at 0x4024B32: strncmp (in
/usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==8951== by 0x422C587: _getopt_internal_r (in /lib/libc-2.11.1.so)
==8951== by 0x422D42D: _getopt_internal (in /lib/libc-2.11.1.so)
==8951== by 0x422D678: getopt_long (in /lib/libc-2.11.1.so)
==8951== by 0x804A5BB: ??? (in /usr/bin/skvm)
==8951== by 0x418FB85: (below main) (in /lib/libc-2.11.1.so)
==8951== If you believe this happened as a result of a stack
==8951== overflow in your program's main thread (unlikely but
==8951== possible), you can try to increase the size of the
==8951== main thread stack using the --main-stacksize= flag.
==8951== The main thread stack size used in this run was 8388608.
==8951==
==8951== HEAP SUMMARY:
==8951== in use at exit: 0 bytes in 0 blocks
==8951== total heap usage: 0 allocs, 0 frees, 0 bytes allocated
==8951==
==8951== All heap blocks were freed -- no leaks are possible
==8951==
==8951== For counts of detected and suppressed errors, rerun with: -v
==8951== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 31 from 8)
Segmentation fault

[jonas_AT_jarchy ~]$ gdb skvm
Reading symbols from /usr/bin/skvm...(no debugging symbols found)...done.
(gdb) run --help
Starting program: /usr/bin/skvm --help
[Thread debugging using libthread_db enabled]

Program received signal SIGSEGV, Segmentation fault.
0xb7dbcf6e in strncmp () from /lib/libc.so.6
(gdb) quit

---- End Valgrind/gdb output ----
Received on Tue Feb 09 2010 - 21:50:49 UTC