diff options
| author | Matthew Wilcox <[email protected]> | 2019-03-05 15:46:06 -0800 |
|---|---|---|
| committer | Linus Torvalds <[email protected]> | 2019-03-05 21:07:17 -0800 |
| commit | 0ee930e6cafa048c1925893d0ca89918b2814f2c (patch) | |
| tree | 583057c2957c316cbb52378c8758c408b676d216 | |
| parent | 2d432cb7091e99881af803cdd67a31969b863005 (diff) | |
mm/memory.c: prevent mapping typed pages to userspace
Pages which use page_type must never be mapped to userspace as it would
destroy their page type. Add an explicit check for this instead of
assuming that kernel drivers always get this right.
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Matthew Wilcox <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Reviewed-by: David Hildenbrand <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
| -rw-r--r-- | mm/memory.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/memory.c b/mm/memory.c index a9897dcd530f..79e0173a7d70 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1452,7 +1452,7 @@ static int insert_page(struct vm_area_struct *vma, unsigned long addr, spinlock_t *ptl; retval = -EINVAL; - if (PageAnon(page) || PageSlab(page)) + if (PageAnon(page) || PageSlab(page) || page_has_type(page)) goto out; retval = -ENOMEM; flush_dcache_page(page); |