Bhupesh, On Fri, Mar 16, 2018 at 03:05:10PM +0530, Bhupesh Sharma wrote: > On Wed, Mar 14, 2018 at 11:54 PM, Mark Rutland <mark.rutland@xxxxxxx> wrote: > > On Wed, Mar 14, 2018 at 11:10:53AM +0900, AKASHI Takahiro wrote: > >> If kaslr-seed has a critical value in terms of security, is kexec-tools > >> a right place? It is exposed to user space albeit for a short time of period. > > > > The kernel zeroes the seed in the DT at boot time, so the current seed > > isn't visible to userspace. > > > > If kexec-tools generates a seed, and inserts it into the DTB that it > > loads, this is only visible to kexec tools or other applications which > > can inspect its memory, so I don't think this is much of a concern. > > Anything with such privilege can presumably kexec() to arbitrary code > > anyhow. > > > > The next kernel will then zero its seed in the DT at boot time, so > > similarly this won't be visible to userspace on the new kernel. > > > > FWIW, having kexec tools generate a seed for the kexec_load() case makes > > sense to me. > > Fair enough. I will try to take a stab at the same and come back with > my findings on this thread. How's your progress here? I've already added kaslr support (i.e. "virtual randomisation") to my kexec_file patch set. # just a few lines of code, though -Takahiro AKASHI > Thanks, > Bhupesh _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
