vm audit: add VM_DONTEXPAND to mmap for drivers that need it
Drivers that register a ->fault handler, but do not range-check the
offset argument, must set VM_DONTEXPAND in the vm_flags in order to
prevent an expanding mremap from overflowing the resource.
I've audited the tree and attempted to fix these problems (usually by
adding VM_DONTEXPAND where it is not obvious).
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/relay.c b/kernel/relay.c
index 61134eb..7c03733 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -92,6 +92,7 @@
return -EINVAL;
vma->vm_ops = &relay_file_mmap_ops;
+ vma->vm_flags |= VM_DONTEXPAND;
vma->vm_private_data = buf;
buf->chan->cb->buf_mapped(buf, filp);