Problem with rtems_task_variable_delete

[Fernando RUIZ CASAS]

On Mon, 08 Dec 2003 22:58:15 +0100, Dieter Schaefer wrote:
Hi,

  The same problem ago.

  A patch has be submitted longtime ago to resolve this concern.

  The problem is that a new implementation of core has been done.

  The problem is in 
  /rtems/cpukit/rtems/src/taskvariabledelete.c

  at line 59
   _Workspace_free(tvp) needs be changed by
   
   _Workspace_free(*tvp) perhaphs. (I can't test it,sorry)

  It's a problem resolved but with the new implementation the problem arrives again.

  A lot of mails have been interchanged with Joel to obtain a patch in the core.
  
  BRGDS. 
  The author of rtems_telnetd.

   

  
> 
> Hello,
> 
> trying to get telnetd to work (powerpc, rtems-4.6.0pre5) I experienced 
> the following problem ...
> trying various commands everything seems to work Ok, until I try to 
> logoff from the telnet session. The system crashes, mean end up 
> in the BSP panic handler.
> Digging into the problem, it seems to be related with deleting a task variable.
> If the task variable contains a pointer to malloc'ed memory and 'free' is 
> passed to rtems_task_variable_add it will crash on deleting the task. 
> Background: telnetd uses shell, and shell creates a 'user environment' 
> after issuing a 'logoff', shell tries to execute a 
> rtems_task_delete( RTEMS_SELF );  
> which in turn, at some point calls 
> rtems_task_variable_delete(RTEMS_SELF, ... ); 
> 
> The same behavior can be reproduces with a slightly modified version 
> of 'ticker test'  
> Adding a task variable pointing to malloc'ed space, assign different values 
> etc. and deleting this space manually after 'rtems_task_variable_delete' 
> everything works Ok. Passing 'free' to automatically delete this space, it 
> ends up in the BSP panic handler.
> 

> Did anybody experienced the same/similar problem? Or, even better, 
> has a fix or work-around? 
> 
> Any information or hint is appreciated.
> 
> Thanks
> Dieter Schaefer
> 
> PS: FTP and Web-Server runs all day long even under heavy load and 
> with continuous ping on FEC and SCCx. 

FTP calls chroot() and chroot() builds a nes user environment the same way that telnetd.
but FTPD runs forever.