[Bug gdb/13333] In some case，when remote target is disconnectted，but GDB try to delete breakpoints by send z0 packet, it will cause GDB crash

["ggs334 at 163 dot com" <sourceware-bugzilla@sourceware.org>]

http://sourceware.org/bugzilla/show_bug.cgi?id=13333

gaohusheng <ggs334 at 163 dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|                            |X86-linux
               Host|                            |X86-linux
   Target Milestone|---                         |7.1
            Summary|In some case，when remote    |In some case，when remote
                   |target is disconnectted，but |target is disconnectted，but
                   |GDB                         |GDB try to delete
                   |                            |breakpoints by send z0
                   |                            |packet, it will cause GDB
                   |                            |crash

--- Comment #1 from gaohusheng <ggs334 at 163 dot com> 2011-10-23 08:55:47 UTC ---
In some case，when remote target is disconnectted，but GDB try to delete
breakpoints by send z0 packet, it will cause GDB crash

===========my test case================

<stdio.h>

int main()

{

 int j=0;

 j++;

 j++;

 j++;

 j++;

 j++;

 j++;

 j++;

 j++;

 return 0;

}


I test this case on:
host: x86-linux GDB;
target x86-linux GDBserver;

[guosheng_gao@rslpc1 nat-7.3]$ bin/gdb

GNU gdb (GDB) 7.3.1

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 "i686-pc-linux-gnu".

For bug reporting instructions, please see:

<http://www.gnu.org/software/gdb/bugs/>.

(gdb) file ~/test/gao2

Reading symbols from /home/guosheng_gao/test/gao2...done.

(gdb) b main

Breakpoint 1 at 0x8048340: file gao2.c, line 4.

(gdb) target remote :1234

Remote debugging using :1234

Reading symbols from /lib/ld-linux.so.2...(no debugging symbols found)...done.

Loaded symbols for /lib/ld-linux.so.2

0x005197c0 in _start () from /lib/ld-linux.so.2

(gdb) c

Continuing.



Breakpoint 1, main () at gao2.c:4

4        int j=0;

(gdb) n

5        j++;

(gdb)

6        j++;

(gdb)

7        j++;

(gdb)

8        j++;

(gdb)

9        j++;

(gdb)

10       j++;

(gdb)

11       j++;

(gdb)

12       j++;

(gdb)

13       return 0;

(gdb) set debug remote 1

(gdb) n

(gdb) n
14      }
(gdb) n

(gdb) n

Single stepping until exit from function __libc_start_main,

which has no line number information.
...........................
==============I have omit some packet information=========
...........................

Sending packet: $vCont;c#a8...Packet received: W00


=================why this happen? ==================
[Inferior 1 (Remote target) exited normally]

Sending packet: $z0,529bd0,1#c9...Segmentation fault (core dumped)
=================why this happen? ==================


[guosheng_gao@rslpc1 nat-7.3]$

[guosheng_gao@rslpc1 nat-7.3]$ [Inferior 1 (Remote target) exited normally]

Badly placed ()'s.

[guosheng_gao@rslpc1 nat-7.3]$ Sending packet: $z0,529bd0,1#c9...Segmentation
fa                                              ult (core dumped)

Badly placed ()'s.

==============GDB server===============

GDBserver:
[guosheng_gao@rslpc1 nat-7.3]$ bin/gdbserver :1234 ~/test/gao2

Process /home/guosheng_gao/test/gao2 created; pid = 3182

Listening on port 1234

Remote debugging from host 127.0.0.1



Child exited with status 0

GDBserver exiting

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