Re: Needed for the release

[Dan Nicolaescu <dann@ics.uci.edu>]

Masatake YAMATO <jet@gyve.org> writes:

  > Sorry to be late.
  > 
  > > Richard Stallman <rms@gnu.org> writes:
  > > 
  > > > What I remember is that Red Hat enables a feature in Linux that (I
  > > > believe) uses the address space differently.  unexelf.c doesn't handle
  > > > it right.
  > > >
  > > > I don't remember the name of the feature, but I'm sure other people
  > > > on this list remember the name.
  > > 
  > > exec_shield is one such feature, and newer kernels use something like,
  > > uh, /proc/sys/vm/randomize_... (I don't remember the particular name
  > > right now and don't have a Fedora active).  The latter loaded
  > > executables' memory segments into randomized locations to make buffer
  > > overflow attacks less predictable.
  > > 
  > > exec_shield could be gotten around with using
  > > setarch i386 make
  > > and configure does that already IIRC.  But the address space
  > > randomization was prohibiting the dumping even with the setarch
  > > command.
  > 
  > Could you tell me the kernel version or the OS version?
  > 
  > I'm using Fedora core 1 and Fedora core 3.
  > I cannot reproduce the problem on the platforms.

The problem occurs in Fedora Core 4.
On a FC4 system:
echo 0 > /proc/sys/kernel/randomize_va_space
is required in order to be able to dump Emacs.