[Mageia-dev] About syslinux & libpng

Tue Oct 4 11:30:29 CEST 2011

On Monday, 3 October 2011 15:58:36 Michael Scherer wrote:
+
+> Except if I start to replace this by "here is a nice syslinux boot image
+> with a duck". And then my code is run by syslinux, just because someone
+> took my png picture.
+
+And the same person could say, "Here is my cool plymouth splash screen, use my 
+initrd", and there are 1000 easier ways to exploit this (than trying to 
+generate a PNG image with exploit code that someone would like enough to use 
+syslinux).
+
+<troll>
+Maybe we need to adopt secure UEFI, and sign our kernels and initial ram disks 
+...
+</troll>
+
+> So no, bundling is not without causing trouble.
+> 
+> > So if we take this road of removing bootloader's libs, shall we also
+> > remove the jpeg/gz/gcc/... libs too, and maybe for other bootloaders too
+> > ?
+> > 
+> > I do understand the need for the application that runs under linux...
+> > but about the bootloaders...
+> 
+> Unless I am wrong, a bootloader run on ring 0 or can even ( like xen )
+> be used to run the kernel in a specific separate memory space ( ie,
+> virtualisation ). This could open a whole new range of problem ( like
+> the Blue Pill concept code published 5 years ago by Joanna Rutkowska )
+> 
+> So I think that bootloader requires more consideration than regular
+> application.
+> 
+> > What's your thoughts about it ?
+> > Would you agree on keep syslinux untouched regarding the png lib ?
+> 
+> For reasons explained before, I would rather disagree.
+
+But, users foolish enough to be tricked into booting malicious code can't 
+really be helped.
+
+I think it would be better if syslinux was compatible with current upstream 
+libpng, so, if:
+1)There is an upstream bug filed regarding support for current libpng
+2)We have a registry of software building statically or with internal copies 
+of libraries, and syslinux is added with a reference to the upstream bug
+
+then I think it is reasonable to build syslinux with internal libpng. Unless 
+you are going to mitigate *all* other attack vectors based on 'here, boot my 
+random binaries on your system'.
+
+Regards,
+Buchan
+