[PATCH 0/3] ash: fix segfault when sourcing a file

[Ron Yorston]

In a message entitled 'segfault while sourcing a file' Bastian Bittorf
reported a problem sourcing a file that tried to run a non-exeutable
script:

   http://lists.busybox.net/pipermail/busybox/2015-August/083228.html

My previous attempt to fix this caused one of the existing ash tests
to fail.  My revised fix avoids that issue.

But nothing's ever as simple as that.  In testing the fix I noticed
that after running the command to reproduce the problem:

   command . /tmp/test.sh

my shell had an additional level of nesting.  So I've picked up a
patch from dash to fix that too.

Ron