Messages in this thread | | | Date | Thu, 4 Apr 2024 14:39:20 -0700 | From | Deepak Gupta <> | Subject | Re: [PATCH v3 09/29] mm: abstract shadow stack vma behind `vma_is_shadow_stack` |
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On Thu, Apr 04, 2024 at 09:02:17PM +0200, David Hildenbrand wrote: >On 04.04.24 01:34, Deepak Gupta wrote: >> } >>- } else if (!(vm_flags & VM_READ)) { >>+ } else if (!(vm_flags & VM_READ) && !vma_is_shadow_stack(vm_flags)) { >>+ /* reads allowed if its shadow stack vma */ >> if (!(gup_flags & FOLL_FORCE)) >> return -EFAULT; >> /* > >Unless I am missing something, this is not a simple cleanup. It should >go into a separate patch with a clearly documented reason for that >change.
I tried that here https://lore.kernel.org/linux-mm/CAKC1njTPBqtsAOn-CWhB+-8FaZ2KWkkz-vRZr7MZq=0yLUdjcQ@mail.gmail.com/T/ But at that time, VM_SHADOW_STACK for riscv meant only VM_WRITE. So I think there was obvious uneasiness with that part.
Now we have VM_SHADOW_STACK pretty much same for all arches and only 64bit. I'll try it again as a separate patch.
> >-- >Cheers, > >David / dhildenb >
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