path: root/mm/memory.c
diff options
authorMatthew Wilcox <willy@infradead.org>2019-03-05 15:46:02 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2019-03-05 21:07:17 -0800
commit2d432cb7091e99881af803cdd67a31969b863005 (patch)
tree6482724693aae6407eeb30d339aebef534e850bd /mm/memory.c
parentmm/vmalloc.c: fix kernel BUG at mm/vmalloc.c:512! (diff)
mm: prevent mapping slab pages to userspace
It's never appropriate to map a page allocated by SLAB into userspace. A buggy device driver might try this, or an attacker might be able to find a way to make it happen. Christoph said: : Let's just fail the code. Currently this may work with SLUB. But SLAB : and SLOB overlay fields with mapcount. So you would have a corrupted page : struct if you mapped a slab page to user space. Link: http://lkml.kernel.org/r/20190125173827.2658-1-willy@infradead.org Signed-off-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Pekka Enberg <penberg@kernel.org> Cc: Rik van Riel <riel@surriel.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/memory.c b/mm/memory.c
index 222da66f16b4..a9897dcd530f 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))
+ if (PageAnon(page) || PageSlab(page))
goto out;
retval = -ENOMEM;