On Wed Dec 08, 2010 at 11:58:58, John Jacobs wrote: > > > I've included here a proof-of-concept local privilege escalation exploit > > for Linux. Please read the header for an explanation of what's going > > on. Without further ado, I present full-nelson.c: > > Hello Dan, is this exploitation not mitigated by best practice > defense-in-depth strategies such as preventing the CAP_SYS_MODULE > capability or '/sbin/sysctl -w kernel.modules_disabled=1' respectively? > It seems it'd certainly stop the Econet/Acorn issue. > > Curious to hear your input as I fear too many rely solely on errata updates and not a good defense-in-depth approach. Only for this proof-of-concept exploit. The real culprit is CVE-2010-4258. Commit 33dd94ae1ccbfb7bf0fb6c692bc3d1c4269e6177 in Linus kernel tree fixes the issue by doing set_fs(USER_DS) early in do_exit(). I guess this will be in pushed to stable series as well.
