linux-ext4 - Re: [PATCH 06/10] e2fsck: require i_size == fscrypt_symlink

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Date:   Sat, 3 Mar 2018 17:09:41 -0500
From:   Theodore Ts'o <tytso@....edu>
To:     Eric Biggers <ebiggers3@...il.com>
Cc:     linux-ext4@...r.kernel.org, Eric Biggers <ebiggers@...gle.com>
Subject: Re: [PATCH 06/10] e2fsck: require i_size == fscrypt_symlink_data.len
 + 2

On Fri, Mar 02, 2018 at 04:59:19PM -0800, Eric Biggers wrote:
> From: Eric Biggers <ebiggers@...gle.com>
> 
> e2fsck validates that unencrypted symlinks have their strlen() equal to
> i_size.  But it skips the equivalent check of i_size ==
> fscrypt_symlink_data.len + 2 for encrypted symlinks.  Actually, the
> encrypted symlink header is redundant with i_size and shouldn't exist.
> But it's there, and the kernel does in fact use the length in the header
> instead of i_size -- so e2fsck should validate the header.
> 
> Thus, remove the exception for encrypted symlinks, so e2fsck will now
> require i_size == fscrypt_symlink_data.len + 2.  I think the exception
> was only there originally because for encrypted fast symlinks we were
> calculating the length using strnlen() which was wrong.  But that was
> fixed by the previous patch.
> 
> Signed-off-by: Eric Biggers <ebiggers@...gle.com>

Thanks, applied.

					- Ted