From 5b2a828b98ec1872799b1b4d82113c76a12d594f Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Wed, 23 Sep 2020 22:47:21 -0700 Subject: [PATCH] fscrypt: export fscrypt_d_revalidate() 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 Link: https://lore.kernel.org/r/20200924054721.187797-1-ebiggers@kernel.org Signed-off-by: Eric Biggers --- fs/crypto/fname.c | 3 ++- include/linux/fscrypt.h | 7 +++++++ 2 files changed, 9 insertions(+), 1 deletion(-) diff --git a/fs/crypto/fname.c b/fs/crypto/fname.c index c65979452844..1fbe6c24d705 100644 --- a/fs/crypto/fname.c +++ b/fs/crypto/fname.c @@ -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, diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h index f1757e73162d..a8f7a43f031b 100644 --- a/include/linux/fscrypt.h +++ b/include/linux/fscrypt.h @@ -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) {