stat should not stack

[p5pRT]

Migrated from rt.perl.org#123816 (status was 'resolved')

Searchable as RT123816$

[p5pRT]

From @hvds

AFL (<http​://lcamtuf.coredump.cx/afl>) finds this​:

% ./miniperl -e 'stat-t'
miniperl​: op.c​:721​: Perl_op_free​: Assertion `!(o->op_private & ~PL_op_private_valid[type])' failed.
Aborted (core dumped)
%

When trying to stack filetests, ck_ftst() checks that the kid is not a stat or lstat, but doesn't check the parent. I think the fix is just to add the check​:

--- a/op.c
+++ b/op.c
@​@​ -9876,8 +9876,10 @​@​ Perl_ck_ftst(pTHX_ OP *o)
  }
  if ((PL_hints & HINT_FILETEST_ACCESS) && OP_IS_FILETEST_ACCESS(o->op_type))
  o->op_private |= OPpFT_ACCESS;
- if (PL_check[kidtype] == Perl_ck_ftst
- && kidtype != OP_STAT && kidtype != OP_LSTAT) {
+ if (type != OP_STAT && type != OP_LSTAT
+ && PL_check[kidtype] == Perl_ck_ftst
+ && kidtype != OP_STAT && kidtype != OP_LSTAT
+ ) {
  o->op_private |= OPpFT_STACKED;
  kid->op_private |= OPpFT_STACKING;
  if (kidtype == OP_FTTTY && (

.. and will push that with a test if nobody disagrees.

Hugo

[p5pRT]

From @hvds

Now fixed with 87ebf1e​:

  [perl #123816] fix stat stacking
 
  The check function for filetests avoids treating '-t stat' as a pair of
  stackable filetests, but needs also to avoid treating 'stat -t' as
  stackable.

Hugo

[p5pRT]

@hvds - Status changed from 'new' to 'pending release'

[p5pRT]

From @khwilliamson

Thank you for submitting this ticket.

The issue should now be resolved with the release today of Perl v5.22, which is available at http​://www.perl.org/get.html
--
Karl Williamson for the Perl 5 team

[p5pRT]

@khwilliamson - Status changed from 'pending release' to 'resolved'