On Mon, Dec 18, 2017 at 12:42:17PM +0100, Thomas Gleixner wrote: > From: Andy Lutomirski <[email protected]> > > The kernel is very erratic as to which pagetables have _PAGE_USER set. The > vsyscall page gets lucky: it seems that all of the relevant pagetables are > among the apparently arbitrary ones that set _PAGE_USER. Rather than > relying on chance, just explicitly set _PAGE_USER. > > This will let us clean up pagetable setup to stop setting _PAGE_USER. The > added code can also be reused by pagetable isolation to manage the > _PAGE_USER bit in the usermode tables. > > Signed-off-by: Andy Lutomirski <[email protected]> > Signed-off-by: Ingo Molnar <[email protected]> > Signed-off-by: Thomas Gleixner <[email protected]> > Cc: Borislav Petkov <[email protected]> > Cc: Brian Gerst <[email protected]> > Cc: David Laight <[email protected]> > Cc: Kees Cook <[email protected]> > Cc: Linus Torvalds <[email protected]> > Cc: Peter Zijlstra <[email protected]> > Cc: Thomas Gleixner <[email protected]> > --- > arch/x86/entry/vsyscall/vsyscall_64.c | 33 > ++++++++++++++++++++++++++++++++- > 1 file changed, 32 insertions(+), 1 deletion(-)
Nice. Reviewed-by: Borislav Petkov <[email protected]> -- Regards/Gruss, Boris. SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg) --
