Re: [PATCH 6.12] ext4: don't enable DAX on new encrypted files

[sashiko-bot@kernel.org]

> commit da32af420d6d466e247c43ac0b829edeac7ae0ad upstream.
> 
> Currently, when a new encrypted regular file is created, the call to
> ext4_set_inode_flags(inode, init=true) in __ext4_new_inode() is made
> before EXT4_INODE_ENCRYPT is set.  As a result, it can set S_DAX if the
> filesystem is mounted with "-o dax=always".
> 
> EXT4_INODE_ENCRYPT then actually gets set a bit later in
> __ext4_new_inode(), when it calls fscrypt_set_context() which calls
> ext4_set_context().  ext4_set_context() sets EXT4_INODE_ENCRYPT and
> calls ext4_set_inode_flags(inode, init=false) to set S_ENCRYPTED too.
> 
> This was intended to clear S_DAX as well.  However, this was broken by
> commit 043546e46dc7 ("fs/ext4: Only change S_DAX on inode load").  This
> causes data written to the file to bypass encryption, also causing
> [ ... ]
> Tested-by: Disha Goel <disgoel@linux.ibm.com>
> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
> Reviewed-by: Jan Kara <jack@suse.cz>
> Link: https://patch.msgid.link/20260730175212.36923-1-ebiggers@kernel.org
> Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Sashiko has reviewed this patch and found no issues. It looks great!

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Sashiko AI review · https://sashiko.dev/#/patchset/20260827032815.82363-1-ebiggers@kernel.org?part=1