On Sat, Nov 17, 2012 at 1:27 AM, Greg Kroah-Hartman <gre...@linuxfoundation.org> wrote: > On Fri, Nov 16, 2012 at 04:20:16PM -0800, Kees Cook wrote: >> Since devtmpfs is writable, make the default noexec nosuid as well. This >> protects from the case of a privileged process having an arbitrary file >> write flaw and an argumentless arbitrary execution (i.e. it would lack >> the ability to run "mount -o remount,exec,suid /dev"), with a system >> that already has nosuid,noexec on all other writable mounts. >> >> Cc: ellyjo...@chromium.org >> Signed-off-by: Kees Cook <keesc...@chromium.org> >> --- >> drivers/base/devtmpfs.c | 6 ++++-- >> 1 file changed, 4 insertions(+), 2 deletions(-) > > Have you tested this to verify that it doesn't break anything? > > Kay, could this cause any problems that you could think of?
It breaks all sorts of old, possibly outdated, stuff, that does things like mapping /dev/mem executable. It for sure used to break X drivers, that fiddle with the BIOS of cards. Kay -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/