Merge tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt

Pull fscrypt updates from Ted Ts'o:
 "Clean up fscrypt's dcache revalidation support, and other
  miscellaneous cleanups"

* tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt:
  fscrypt: cache decrypted symlink target in ->i_link
  vfs: use READ_ONCE() to access ->i_link
  fscrypt: fix race where ->lookup() marks plaintext dentry as ciphertext
  fscrypt: only set dentry_operations on ciphertext dentries
  fs, fscrypt: clear DCACHE_ENCRYPTED_NAME when unaliasing directory
  fscrypt: fix race allowing rename() and link() of ciphertext dentries
  fscrypt: clean up and improve dentry revalidation
  fscrypt: use READ_ONCE() to access ->i_crypt_info
  fscrypt: remove WARN_ON_ONCE() when decryption fails
  fscrypt: drop inode argument from fscrypt_get_ctx()

1 files changed, 47 insertions, 15 deletions

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index ef755e5f6f2f..1cb67859e051 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -2303,23 +2303,47 @@ extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
 
 #ifdef CONFIG_FS_ENCRYPTION
+static inline void ext4_fname_from_fscrypt_name(struct ext4_filename *dst,
+                                                const struct fscrypt_name *src)
+{
+        memset(dst, 0, sizeof(*dst));
+
+        dst->usr_fname = src->usr_fname;
+        dst->disk_name = src->disk_name;
+        dst->hinfo.hash = src->hash;
+        dst->hinfo.minor_hash = src->minor_hash;
+        dst->crypto_buf = src->crypto_buf;
+}
+
 static inline int ext4_fname_setup_filename(struct inode *dir,
-                        const struct qstr *iname,
-                        int lookup, struct ext4_filename *fname)
+                                            const struct qstr *iname,
+                                            int lookup,
+                                            struct ext4_filename *fname)
 {
         struct fscrypt_name name;
         int err;
 
-        memset(fname, 0, sizeof(struct ext4_filename));
-
         err = fscrypt_setup_filename(dir, iname, lookup, &name);
+        if (err)
+                return err;
 
-        fname->usr_fname = name.usr_fname;
-        fname->disk_name = name.disk_name;
-        fname->hinfo.hash = name.hash;
-        fname->hinfo.minor_hash = name.minor_hash;
-        fname->crypto_buf = name.crypto_buf;
-        return err;
+        ext4_fname_from_fscrypt_name(fname, &name);
+        return 0;
+}
+
+static inline int ext4_fname_prepare_lookup(struct inode *dir,
+                                            struct dentry *dentry,
+                                            struct ext4_filename *fname)
+{
+        struct fscrypt_name name;
+        int err;
+
+        err = fscrypt_prepare_lookup(dir, dentry, &name);
+        if (err)
+                return err;
+
+        ext4_fname_from_fscrypt_name(fname, &name);
+        return 0;
 }
 
 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
@@ -2333,19 +2357,27 @@ static inline void ext4_fname_free_filename(struct ext4_filename *fname)
         fname->usr_fname = NULL;
         fname->disk_name.name = NULL;
 }
-#else
+#else /* !CONFIG_FS_ENCRYPTION */
 static inline int ext4_fname_setup_filename(struct inode *dir,
-                const struct qstr *iname,
-                int lookup, struct ext4_filename *fname)
+                                            const struct qstr *iname,
+                                            int lookup,
+                                            struct ext4_filename *fname)
 {
         fname->usr_fname = iname;
         fname->disk_name.name = (unsigned char *) iname->name;
         fname->disk_name.len = iname->len;
         return 0;
 }
-static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
 
-#endif
+static inline int ext4_fname_prepare_lookup(struct inode *dir,
+                                            struct dentry *dentry,
+                                            struct ext4_filename *fname)
+{
+        return ext4_fname_setup_filename(dir, &dentry->d_name, 1, fname);
+}
+
+static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
+#endif /* !CONFIG_FS_ENCRYPTION */
 
 /* dir.c */
 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,