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| author |   Dan Williams <dan.j.williams@intel.com> | 2017-11-29 16:10:21 -0800 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2017-11-29 18:40:42 -0800 |
| commit | 5c9d2d5c269c498aa9a546e8d2158a3e4142a1a2 (patch) | |
| tree | b8454bda3e8830a40159b89b2d8cdf3412d0ac25 /mm/memory.c | |
| parent | mm: replace pmd_write with pmd_access_permitted in fault + gup paths (diff) | |
| download | linux-dev-5c9d2d5c269c498aa9a546e8d2158a3e4142a1a2.tar.xz linux-dev-5c9d2d5c269c498aa9a546e8d2158a3e4142a1a2.zip | |
mm: replace pte_write with pte_access_permitted in fault + gup paths
The 'access_permitted' helper is used in the gup-fast path and goes
beyond the simple _PAGE_RW check to also:
- validate that the mapping is writable from a protection keys
standpoint
- validate that the pte has _PAGE_USER set since all fault paths where
pte_write is must be referencing user-memory.
Link: http://lkml.kernel.org/r/151043111604.2842.8051684481794973100.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
| -rw-r--r-- | mm/memory.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/mm/memory.c b/mm/memory.c index 416e451a707e..4f07acd1695f 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3948,7 +3948,7 @@ static int handle_pte_fault(struct vm_fault *vmf) if (unlikely(!pte_same(*vmf->pte, entry))) goto unlock; if (vmf->flags & FAULT_FLAG_WRITE) { - if (!pte_write(entry)) + if (!pte_access_permitted(entry, WRITE)) return do_wp_page(vmf); entry = pte_mkdirty(entry); } @@ -4336,7 +4336,7 @@ int follow_phys(struct vm_area_struct *vma, goto out; pte = *ptep; - if ((flags & FOLL_WRITE) && !pte_write(pte)) + if (!pte_access_permitted(pte, flags & FOLL_WRITE)) goto unlock; *prot = pgprot_val(pte_pgprot(pte)); |