fscrypt: export fscrypt_d_revalidate() (5b2a828b) · Commits · 戴 / test

Dentries that represent no-key names must have a dentry_operations that includes fscrypt_d_revalidate(). Currently, this is handled by fscrypt_prepare_lookup() installing fscrypt_d_ops. However, ceph support for encryption (https://lore.kernel.org/r/20200914191707.380444-1-jlayton@kernel.org) can't use fscrypt_d_ops, since ceph already has its own dentry_operations. Similarly, ext4 and f2fs support for directories that are both encrypted and casefolded (https://lore.kernel.org/r/20200923010151.69506-1-drosen@google.com ) can't use fscrypt_d_ops either, since casefolding requires some dentry operations too. To satisfy both users, we need to move the responsibility of installing the dentry_operations to filesystems. In preparation for this, export fscrypt_d_revalidate() and give it a !CONFIG_FS_ENCRYPTION stub. Reviewed-by:

Jeff Layton <jlayton@kernel.org> Link: https://lore.kernel.org/r/20200924054721.187797-1-ebiggers@kernel.org Signed-off-by:

Eric Biggers <ebiggers@google.com>

fs/crypto/fname.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -530,7 +530,7 @@ EXPORT_SYMBOL_GPL(fscrypt_fname_siphash);
		* Validate dentries in encrypted directories to make sure we aren't potentially
		* caching stale dentries after a key has been added.
		*/
		static int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags)
		int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags)
		{
		struct dentry *dir;
		int err;
		@@ -569,6 +569,7 @@ static int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags)

		return valid;
		}
		EXPORT_SYMBOL_GPL(fscrypt_d_revalidate);

		const struct dentry_operations fscrypt_d_ops = {
		.d_revalidate = fscrypt_d_revalidate,

include/linux/fscrypt.h

+7 −0

Original line number	Diff line number	Diff line
		@@ -197,6 +197,7 @@ int fscrypt_fname_disk_to_usr(const struct inode *inode,
		bool fscrypt_match_name(const struct fscrypt_name *fname,
		const u8 *de_name, u32 de_name_len);
		u64 fscrypt_fname_siphash(const struct inode dir, const struct qstr name);
		int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags);

		/* bio.c */
		void fscrypt_decrypt_bio(struct bio *bio);
		@@ -454,6 +455,12 @@ static inline u64 fscrypt_fname_siphash(const struct inode *dir,
		return 0;
		}

		static inline int fscrypt_d_revalidate(struct dentry *dentry,
		unsigned int flags)
		{
		return 1;
		}

		/* bio.c */
		static inline void fscrypt_decrypt_bio(struct bio *bio)
		{

Admin message