Is this the same bit of logic in 2.4.7:
good_area:
write = 0;
si_code = SEGV_ACCERR;
switch (error_code & 0xFF) {
case 0x04: /* write,
present*/
write = 1;
break;
case 0x10: /* not
present*/
case 0x11: /* not
present*/
if (!(vma->vm_flags & (VM_READ | VM_EXEC |
VM_WRITE)))
goto bad_area;
---->>>> Insert patch here?
break;
default:
printk("code should be 4, 10 or 11 (%lX)
\n",error_code&0xFF);
goto bad_area;
}
> -----Original Message-----
> Hi Jason,
> > I've tried the attached simple program on RedHat 2.4.9-17 and
> > the lastest 2.4.17 build from IBM, and both fail miserably:
>
> This is a bug in arch/{s390,s390x}/mm/fault.c that is present
> since the
> beginning. A small wonder that nobody noticed it until now...
> The following patch should take care of it:
>
> diff -urN linux-2.4.17/arch/s390/mm/fault.c
> linux-2.4.17-s390/arch/s390/mm/fault.c
> --- linux-2.4.17/arch/s390/mm/fault.c Wed May 22 20:18:55 2002
> +++ linux-2.4.17-s390/arch/s390/mm/fault.c Wed May 22
> 20:14:10 2002
> @@ -222,6 +222,9 @@
> /* page not present, check vm flags */
> if (!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)))
> goto bad_area;
> + } else {
> + if (!(vma->vm_flags & VM_WRITE))
> + goto bad_area;
> }
