Re: Preliminary ELF prebinding patches available.

From: Marcel Moolenaar <marcel_at_xcllnt.net>
Date: Mon, 26 May 2003 02:05:03 -0700
On Mon, May 26, 2003 at 10:28:42AM +0200, Brad Knowles wrote:
> At 10:31 PM -0700 2003/05/25, Marcel Moolenaar wrote:
> 
> > Hence, prebind information is decoupled from the executable. One
> > of the more obvious complexities is the fact that the naming scheme
> > is such that multiple binaries can have the same prebind cache file.
> > The collision is currently not handled, other than making sure that
> > the prebind information for binary A1 is not used by binary A2. But
> > other complexities exist. What if by some unlucky draw of faith you
> > have two totally independent executables that both resolve to the
> > same prebind file *and* happen to have the same build ID? You have
> > an undetectable collision.
> 
> 	How painful would it be to do a checksum (ideally, MD5 hash) of 
> the binary in question?  Or at least recording path to the binary 
> within the prebind cache file?  Or maybe file metadata like the 
> ownership, permissions, and date/time stamp?

Not painful, but I don't think it covers the problem. It doesn't
matter where you get the ELF files from or what the permissions
are, you need to make sure that the mix of ELF files (executable
and shared libraries) is the same as when the prebinding cache
was constructed. You also need to take link order into account
if you want to handle multiple instances of weak symbols.

-- 
 Marcel Moolenaar	  USPA: A-39004		 marcel_at_xcllnt.net
Received on Mon May 26 2003 - 00:05:05 UTC

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