From d5bfccdf38d094f2b15fae8b361d7bd47f2509d6 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Mon, 3 Oct 2016 09:46:04 +1100
Subject: [PATCH] ext2: fix possible integer truncation in ext2_iomap_begin

For 32-bit architectures we need to cast first_block to u64 before
shifting it left.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Jan Kara <jack@suse.cz>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
---
 fs/ext2/inode.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index aae5f61f980b..c7dbb4661119 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -806,7 +806,7 @@ static int ext2_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
 
 	iomap->flags = 0;
 	iomap->bdev = inode->i_sb->s_bdev;
-	iomap->offset = first_block << blkbits;
+	iomap->offset = (u64)first_block << blkbits;
 
 	if (ret == 0) {
 		iomap->type = IOMAP_HOLE;