linux-ext4 - i_file_acl bug with 64-bit

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Date:	Thu, 8 Aug 2013 17:20:39 -0600
From:	Andreas Dilger <adilger@...ger.ca>
To:	Theodore Ts'o <tytso@....edu>, Eric Sandeen <sandeen@...hat.com>
Cc:	"linux-ext4@...r.kernel.org List" <linux-ext4@...r.kernel.org>
Subject: i_file_acl bug with 64-bit

I was just looking at a problem with s_mmp_block and its
incorrect check to be within the filesystem - it was checking
that the 64-bit MMP block was below s_blocks_count (i.e. the
low 32 bits) instead of using ext2fs_blocks_count() (a patch
for this will follow).

However, a much bigger problem is that it appears i_file_acl
is being used directly in many places without checking for
i_file_acl_high, so xattr blocks written beyond 2^32 may
incorrectly be considered corrupt by e2fsck, since it is
checking the 32-bit truncated block number.

Unfortunately, I'm on my way out of the house for vacation, but
I thought I'd at least send a note about this.

Cheers, Andreas

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