diff options
author | Dan Williams <dan.j.williams@intel.com> | 2017-11-30 03:10:21 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-11-30 05:40:42 +0300 |
commit | 5c9d2d5c269c498aa9a546e8d2158a3e4142a1a2 (patch) | |
tree | b8454bda3e8830a40159b89b2d8cdf3412d0ac25 /mm/gup.c | |
parent | c7da82b894e9eef60a04a15f065a8502341bf13b (diff) | |
download | linux-5c9d2d5c269c498aa9a546e8d2158a3e4142a1a2.tar.xz |
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 'mm/gup.c')
-rw-r--r-- | mm/gup.c | 2 |
1 files changed, 1 insertions, 1 deletions
@@ -66,7 +66,7 @@ static int follow_pfn_pte(struct vm_area_struct *vma, unsigned long address, */ static inline bool can_follow_write_pte(pte_t pte, unsigned int flags) { - return pte_write(pte) || + return pte_access_permitted(pte, WRITE) || ((flags & FOLL_FORCE) && (flags & FOLL_COW) && pte_dirty(pte)); } |