[Btrfs-devel][PATCH]Fix u32 overflow in dirty_and_release_pages.

[Yan Zheng]

Hello,

At file.c:306

	inline_size = end_pos;
	if (isize >= BTRFS_MAX_INLINE_DATA_SIZE(root) ||
	    inline_size > 32768 ||
	    inline_size >= BTRFS_MAX_INLINE_DATA_SIZE(root))

When 'end_pos' is larger than 2^32,  'inline_size' may become a small
value. In this case, 'dirty_and_release_pages' may try to insert a
very large inline extent.

Regards
YZ
---
diff -r 2456df534a5f file.c
--- a/file.c	Thu Nov 01 19:45:34 2007 -0400
+++ b/file.c	Mon Nov 05 07:41:23 2007 +0800
@@ -239,7 +239,7 @@ static int dirty_and_release_pages(struc
 	u64 start_pos;
 	u64 end_of_last_block;
 	u64 end_pos = pos + write_bytes;
-	u32 inline_size;
+	u64 inline_size;
 	loff_t isize = i_size_read(inode);

 	em = alloc_extent_map(GFP_NOFS);