Re: [PATCH v7 00/10] Set casefold/fscrypt dentry operations through sb->s_d_op

Eric Biggers
2024-02-27T06:36:16Z

On Wed, Feb 21, 2024 at 12:14:02PM -0500, Gabriel Krisman Bertazi wrote:
>
> When case-insensitive and fscrypt were adapted to work together, we moved the
> code that sets the dentry operations for case-insensitive dentries(d_hash and
> d_compare) to happen from a helper inside ->lookup. This is because fscrypt
> wants to set d_revalidate only on some dentries, so it does it only for them in
> d_revalidate.
>
> But, case-insensitive hooks are actually set on all dentries in the filesystem,
> so the natural place to do it is through s_d_op and let d_alloc handle it [1].
> In addition, doing it inside the ->lookup is a problem for case-insensitive
> dentries that are not created through ->lookup, like those coming
> open-by-fhandle[2], which will not see the required d_ops.
>
> This patchset therefore reverts to using sb->s_d_op to set the dentry operations
> for case-insensitive filesystems. In order to set case-insensitive hooks early
> and not require every dentry to have d_revalidate in case-insensitive
> filesystems, it introduces a patch suggested by Al Viro to disable d_revalidate
> on some dentries on the fly.
>
> It survives fstests encrypt and quick groups without regressions. Based on
> v6.7-rc1.
>
> [1] https://lore.kernel.org/linux-fsdevel/20231123195327.GP38156@ZenIV/
> [2] https://lore.kernel.org/linux-fsdevel/20231123171255.GN38156@ZenIV/
>
> Gabriel Krisman Bertazi (10):
> ovl: Always reject mounting over case-insensitive directories
> fscrypt: Factor out a helper to configure the lookup dentry
> fscrypt: Drop d_revalidate for valid dentries during lookup
> fscrypt: Drop d_revalidate once the key is added
> libfs: Merge encrypted_ci_dentry_ops and ci_dentry_ops
> libfs: Add helper to choose dentry operations at mount-time
> ext4: Configure dentry operations at dentry-creation time
> f2fs: Configure dentry operations at dentry-creation time
> ubifs: Configure dentry operations at dentry-creation time
> libfs: Drop generic_set_encrypted_ci_d_ops
>
> fs/crypto/hooks.c | 15 ++++------
> fs/ext4/namei.c | 1 -
> fs/ext4/super.c | 1 +
> fs/f2fs/namei.c | 1 -
> fs/f2fs/super.c | 1 +
> fs/libfs.c | 62 +++++++++++---------------------------
> fs/overlayfs/params.c | 14 +++++++--
> fs/ubifs/dir.c | 1 -
> fs/ubifs/super.c | 1 +
> include/linux/fs.h | 11 ++++++-
> include/linux/fscrypt.h | 66 ++++++++++++++++++++++++++++++++++++-----
> 11 files changed, 105 insertions(+), 69 deletions(-)
>

Looks good,

Reviewed-by: Eric Biggers <ebiggers@google.com>

- Eric