On Thu, Jul 18, 2013 at 06:36:07PM -0700, Kees Cook wrote: > On Thu, Jul 18, 2013 at 6:30 PM, Greg KH <[email protected]> wrote: > > On Fri, Jul 19, 2013 at 01:15:26AM +0000, Linux Kernel Mailing List wrote: > >> Gitweb: > >> http://git.kernel.org/linus/;a=commit;h=4df05f361937ee86e5a8c9ead8aeb6a19ea9b7d7 > >> Commit: 4df05f361937ee86e5a8c9ead8aeb6a19ea9b7d7 > >> Parent: 5ff560fd48d5b3d82fa0c3aff625c9da1a301911 > >> Author: Kees Cook <[email protected]> > >> AuthorDate: Tue Jul 16 11:34:41 2013 -0700 > >> Committer: H. Peter Anvin <[email protected]> > >> CommitDate: Tue Jul 16 15:14:48 2013 -0700 > >> > >> x86: Make sure IDT is page aligned > >> > >> Since the IDT is referenced from a fixmap, make sure it is page > >> aligned. > >> Merge with 32-bit one, since it was already aligned to deal with F00F > >> bug. Since bss is cleared before IDT setup, it can live there. This > >> also > >> moves the other *_idt_table variables into common locations. > >> > >> This avoids the risk of the IDT ever being moved in the bss and having > >> the mapping be offset, resulting in calling incorrect handlers. In the > >> current upstream kernel this is not a manifested bug, but heavily > >> patched > >> kernels (such as those using the PaX patch series) did encounter this > >> bug. > >> > >> The tables other than idt_table technically do not need to be page > >> aligned, at least not at the current time, but using a common > >> declaration avoids mistakes. On 64 bits the table is exactly one page > >> long, anyway. > >> > >> Signed-off-by: Kees Cook <[email protected]> > >> Link: http://lkml.kernel.org/r/[email protected] > >> Reported-by: PaX Team <[email protected]> > >> Signed-off-by: H. Peter Anvin <[email protected]> > >> --- > >> arch/x86/kernel/head_64.S | 15 --------------- > >> arch/x86/kernel/tracepoint.c | 6 ++---- > >> arch/x86/kernel/traps.c | 12 ++++++------ > >> 3 files changed, 8 insertions(+), 25 deletions(-) > > > > This patch is now in Linus's tree. Kees, did you also want this in the > > -stable tree(s)? > > The potential problem was introduced with > 4eefbe792baedb474e256d35370849992fcf1c79, so 3.10 needs it, yes. I had > also sent a much smaller version here: > http://git.kernel.org/cgit/linux/kernel/git/kees/linux.git/commit/?h=idt-stable&id=794c1e0df641e13050cfc4af340fc3c85bed4ea3 > > Either will address the problem. If there is no problem with taking > the larger clean-up for stable, then that's probably easiest.
I'd prefer to stick with what ended up in Linus's tree, so I'll just queue this one up in a future stable 3.10 release, thanks. greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
