two 4GB mallocs => SEGV

[David O'Brien]

On Tue, Oct 26, 2004 at 02:32:27PM -0700, David O'Brien wrote:
> On Tue, Oct 26, 2004 at 12:55:06PM -0500, James R. Van Artsalen wrote:
> > A few months ago I posted this bug in the libc brk(2) code - the stack 
> > is not balanced if the kernel returns an error.  I'm not running current 
> > code at the moment but see if you brk.S has a stack issue at the err: 
> > label.  Stick in this pop if so and report if malloc(3c) then returns 
> > NULL instead of crashing, then up your ulimit and try again and see if 
> > all works without error.
> > 
> > --- lib/libc/amd64/sys/brk.S.~1~        Sat May 24 12:35:23 2003
> > +++ lib/libc/amd64/sys/brk.S    Fri Apr  9 02:02:22 2004
> > @@ -78,6 +78,7 @@
> >        popq    %rdi
> >        ret
> > err:
> > +       popq    %rdi


VERY sorry.  I looked at sbrk.S not brk.S.  Your fix is correct.
                        ^^^

Starting program: /var/tmp/a.out 
3221225472
5255168
3226480640

-- 
-- David    (obrien at NUXI.com)