From 4ba2d5fdcfd19de0dedf394ddc48db2f219fa89a Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@tuxera.com>
Date: Wed, 16 Feb 2011 09:34:22 +0100
Subject: hfsplus: fix overflow in hfsplus_read_wrapper

For partitions larger than 2TB or at such an offset the hfs wrapper code
in hfsplus might overflow the range representable in a 32-bit
data type. Make sure we use a sector_t for the arithmetics leading to it.

I'm not sure this code can be readed at all as hfs itself never supported
such large volumes.

Signed-off-by: Christoph Hellwig <hch@tuxera.com>

diff --git a/fs/hfsplus/wrapper.c b/fs/hfsplus/wrapper.c
index 4ac88ff..4b86468 100644
--- a/fs/hfsplus/wrapper.c
+++ b/fs/hfsplus/wrapper.c
@@ -172,8 +172,9 @@ reread:
 		if (!hfsplus_read_mdb(sbi->s_vhdr, &wd))
 			goto out_free_backup_vhdr;
 		wd.ablk_size >>= HFSPLUS_SECTOR_SHIFT;
-		part_start += wd.ablk_start + wd.embed_start * wd.ablk_size;
-		part_size = wd.embed_count * wd.ablk_size;
+		part_start += (sector_t)wd.ablk_start +
+			       (sector_t)wd.embed_start * wd.ablk_size;
+		part_size = (sector_t)wd.embed_count * wd.ablk_size;
 		goto reread;
 	default:
 		/*
-- 
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