[83/88] ext4: fix data offset overflow in ext4_xattr_fiemap() on 32-bit archs

Steven Rostedt
2013-08-13T16:26:52Z

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3.6.11.7-rc1 stable review patch.
If anyone has any objections, please let me know.

------------------

From: Jan Kara <jack@suse.cz>

[ Upstream commit a60697f411eb365fb09e639e6f183fe33d1eb796 ]

On 32-bit architectures with 32-bit sector_t computation of data offset
in ext4_xattr_fiemap() can overflow resulting in reporting bogus data
location. Fix the problem by typing block number to proper type before
shifting.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
fs/ext4/extents.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 4f7d479..345442f 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4767,7 +4767,7 @@ static int ext4_xattr_fiemap(struct inode *inode,
error = ext4_get_inode_loc(inode, &iloc);
if (error)
return error;
- physical = iloc.bh->b_blocknr << blockbits;
+ physical = (__u64)iloc.bh->b_blocknr << blockbits;
offset = EXT4_GOOD_OLD_INODE_SIZE +
EXT4_I(inode)->i_extra_isize;
physical += offset;
@@ -4775,7 +4775,7 @@ static int ext4_xattr_fiemap(struct inode *inode,
flags |= FIEMAP_EXTENT_DATA_INLINE;
brelse(iloc.bh);
} else { /* external block */
- physical = EXT4_I(inode)->i_file_acl << blockbits;
+ physical = (__u64)EXT4_I(inode)->i_file_acl << blockbits;
length = inode->i_sb->s_blocksize;
}

--
1.7.10.4