From e445ee65cbefaa19131c972ae7fe221c95cf4cc4 Mon Sep 17 00:00:00 2001
From: "David S. Miller" <davem@sunset.davemloft.net>
Date: Sat, 24 Dec 2005 12:06:10 -0800
Subject: [PATCH] [VIDEO] sbuslib: Disallow private mmaps.
The COW semantics just do not make any sense especially
with the physically discontiguous I/O mappings possible
here.
Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/video/sbuslib.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/video/sbuslib.c b/drivers/video/sbuslib.c
index 646c43f921c55..3a74a63dd4f22 100644
--- a/drivers/video/sbuslib.c
+++ b/drivers/video/sbuslib.c
@@ -46,6 +46,9 @@ int sbusfb_mmap_helper(struct sbus_mmap_map *map,
unsigned long off;
int i;
+ if (!(vma->vm_flags & (VM_SHARED | VM_MAYSHARE)))
+ return -EINVAL;
+
size = vma->vm_end - vma->vm_start;
if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))
return -EINVAL;
--
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