Thread

1. [PATCH] fix segfault with DO and plperl/plperlu

   Alex Hunsaker <badalex@gmail.com> — 2010-04-18T06:48:41Z

   If you do:
   
   # DO $do$ 1; $do$ LANGUAGE plperlu;
   # DO $do$ 1; $do$ LANGUAGE plperl;
   
   You get a segfault as we try to SvREFCNT_dec(...); for the wrong
   interpreter.  To fix push down the restore_context() so that we do the
   above on the correct perl interpreter.
   --
    *** a/src/pl/plperl/plperl.c
   --- b/src/pl/plperl/plperl.c
   ***************
   *** 1154,1170 **** plperl_inline_handler(PG_FUNCTION_ARGS)
     	PG_CATCH();
     	{
     		current_call_data = save_call_data;
   - 		restore_context(oldcontext);
     		if (desc.reference)
     			SvREFCNT_dec(desc.reference);
     		PG_RE_THROW();
     	}
     	PG_END_TRY();
   
     	current_call_data = save_call_data;
   - 	restore_context(oldcontext);
     	if (desc.reference)
     		SvREFCNT_dec(desc.reference);
   
     	error_context_stack = pl_error_context.previous;
   
   --- 1154,1170 ----
     	PG_CATCH();
     	{
     		current_call_data = save_call_data;
     		if (desc.reference)
     			SvREFCNT_dec(desc.reference);
   + 		restore_context(oldcontext);
     		PG_RE_THROW();
     	}
     	PG_END_TRY();
   
     	current_call_data = save_call_data;
     	if (desc.reference)
     		SvREFCNT_dec(desc.reference);
   + 	restore_context(oldcontext);
   
     	error_context_stack = pl_error_context.previous;
   

2. Re: [PATCH] fix segfault with DO and plperl/plperlu

   Tom Lane <tgl@sss.pgh.pa.us> — 2010-04-18T19:17:39Z

   Alex Hunsaker <badalex@gmail.com> writes:
   > If you do:
   > # DO $do$ 1; $do$ LANGUAGE plperlu;
   > # DO $do$ 1; $do$ LANGUAGE plperl;
   
   > You get a segfault as we try to SvREFCNT_dec(...); for the wrong
   > interpreter.  To fix push down the restore_context() so that we do the
   > above on the correct perl interpreter.
   
   Hmm.  I don't see a segfault on my machine, but I agree that this looks
   bogus.  I changed it to this order instead:
   
   		if (desc.reference)
   			SvREFCNT_dec(desc.reference);
   		current_call_data = save_call_data;
   		restore_context(oldcontext);
   
   so as to keep the "state restore" operations together.
   
   			regards, tom lane
   
   

3. Re: [PATCH] fix segfault with DO and plperl/plperlu

   Alex Hunsaker <badalex@gmail.com> — 2010-04-18T21:04:22Z

   On Sun, Apr 18, 2010 at 13:17, Tom Lane <tgl@sss.pgh.pa.us> wrote:
   > Alex Hunsaker <badalex@gmail.com> writes:
   >> You get a segfault as we try to SvREFCNT_dec(...);
   >
   > Hmm.  I don't see a segfault on my machine, but I agree that this looks
   > bogus.  I changed it to this order instead:
   > [ ... ]
   > so as to keep the "state restore" operations together.
   
   Even better Thanks!