| From | Yu-cheng Yu <> | Subject | [RFC PATCH v2 15/27] mm/mprotect: Prevent mprotect from changing shadow stack | Date | Tue, 10 Jul 2018 15:26:27 -0700 |
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Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com> --- mm/mprotect.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/mm/mprotect.c b/mm/mprotect.c index 625608bc8962..128dcb880c12 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -446,6 +446,15 @@ static int do_mprotect_pkey(unsigned long start, size_t len, error = -ENOMEM; if (!vma) goto out; + + /* + * Do not allow changing shadow stack memory. + */ + if (vma->vm_flags & VM_SHSTK) { + error = -EINVAL; + goto out; + } + prev = vma->vm_prev; if (unlikely(grows & PROT_GROWSDOWN)) { if (vma->vm_start >= end) -- 2.17.1
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