Messages in this thread | | | Date | Mon, 2 Jul 2018 14:15:28 +0200 | From | Michal Hocko <> | Subject | Re: [RFC v3 PATCH 5/5] x86: check VM_DEAD flag in page fault |
| |
On Mon 02-07-18 10:45:03, Laurent Dufour wrote: > On 30/06/2018 00:39, Yang Shi wrote: > > Check VM_DEAD flag of vma in page fault handler, if it is set, trigger > > SIGSEGV. > > > > Cc: Michal Hocko <mhocko@kernel.org> > > Cc: Thomas Gleixner <tglx@linutronix.de> > > Cc: Ingo Molnar <mingo@redhat.com> > > Cc: "H. Peter Anvin" <hpa@zytor.com> > > Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com> > > --- > > arch/x86/mm/fault.c | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c > > index 9a84a0d..3fd2da5 100644 > > --- a/arch/x86/mm/fault.c > > +++ b/arch/x86/mm/fault.c > > @@ -1357,6 +1357,10 @@ static inline bool smap_violation(int error_code, struct pt_regs *regs) > > bad_area(regs, error_code, address); > > return; > > } > > + if (unlikely(vma->vm_flags & VM_DEAD)) { > > + bad_area(regs, error_code, address); > > + return; > > + } > > This will have to be done for all the supported architectures, what about doing > this check in handle_mm_fault() and return VM_FAULT_SIGSEGV ?
We already do have a model for that. Have a look at MMF_UNSTABLE.
-- Michal Hocko SUSE Labs
| |