fscrypt: clean up fscrypt_add_test_dummy_key()

Now that fscrypt_add_test_dummy_key() is only called by
setup_file_encryption_key() and not by the individual filesystems,
un-export it.  Also change its prototype to take the
fscrypt_key_specifier directly, as the caller already has it.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20230208062107.199831-6-ebiggers@kernel.org

diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
index 17dd33d..0fec2df 100644 (file)
--- a/fs/crypto/fscrypt_private.h
+++ b/fs/crypto/fscrypt_private.h
@@ -573,6 +573,9 @@ fscrypt_find_master_key(struct super_block *sb,
 int fscrypt_get_test_dummy_key_identifier(
                          u8 key_identifier[FSCRYPT_KEY_IDENTIFIER_SIZE]);
 
+int fscrypt_add_test_dummy_key(struct super_block *sb,
+                              struct fscrypt_key_specifier *key_spec);
+
 int fscrypt_verify_key_added(struct super_block *sb,
                             const u8 identifier[FSCRYPT_KEY_IDENTIFIER_SIZE]);
 

diff --git a/fs/crypto/keyring.c b/fs/crypto/keyring.c
index 78dd2ff..78086f8 100644 (file)
--- a/fs/crypto/keyring.c
+++ b/fs/crypto/keyring.c
@@ -211,10 +211,6 @@ static int allocate_filesystem_keyring(struct super_block *sb)
  * are still available at this time; this is important because after user file
  * accesses have been allowed, this function may need to evict keys from the
  * keyslots of an inline crypto engine, which requires the block device(s).
- *
- * This is also called when the super_block is being freed.  This is needed to
- * avoid a memory leak if mounting fails after the "test_dummy_encryption"
- * option was processed, as in that case the unmount-time call isn't made.
  */
 void fscrypt_destroy_keyring(struct super_block *sb)
 {
@@ -778,34 +774,26 @@ out:
 /**
  * fscrypt_add_test_dummy_key() - add the test dummy encryption key
  * @sb: the filesystem instance to add the key to
- * @dummy_policy: the encryption policy for test_dummy_encryption
+ * @key_spec: the key specifier of the test dummy encryption key
  *
- * If needed, add the key for the test_dummy_encryption mount option to the
- * filesystem.  To prevent misuse of this mount option, a per-boot random key is
- * used instead of a hardcoded one.  This makes it so that any encrypted files
- * created using this option won't be accessible after a reboot.
+ * Add the key for the test_dummy_encryption mount option to the filesystem.  To
+ * prevent misuse of this mount option, a per-boot random key is used instead of
+ * a hardcoded one.  This makes it so that any encrypted files created using
+ * this option won't be accessible after a reboot.
  *
  * Return: 0 on success, -errno on failure
  */
 int fscrypt_add_test_dummy_key(struct super_block *sb,
-                              const struct fscrypt_dummy_policy *dummy_policy)
+                              struct fscrypt_key_specifier *key_spec)
 {
-       const union fscrypt_policy *policy = dummy_policy->policy;
-       struct fscrypt_key_specifier key_spec;
        struct fscrypt_master_key_secret secret;
        int err;
 
-       if (!policy)
-               return 0;
-       err = fscrypt_policy_to_key_spec(policy, &key_spec);
-       if (err)
-               return err;
        fscrypt_get_test_dummy_secret(&secret);
-       err = add_master_key(sb, &secret, &key_spec);
+       err = add_master_key(sb, &secret, key_spec);
        wipe_master_key_secret(&secret);
        return err;
 }
-EXPORT_SYMBOL_GPL(fscrypt_add_test_dummy_key);
 
 /*
  * Verify that the current user has added a master key with the given identifier

diff --git a/fs/crypto/keysetup.c b/fs/crypto/keysetup.c
index 20323c0..aa94fba 100644 (file)
--- a/fs/crypto/keysetup.c
+++ b/fs/crypto/keysetup.c
@@ -464,9 +464,7 @@ static int setup_file_encryption_key(struct fscrypt_info *ci,
                 */
                if (dummy_policy &&
                    fscrypt_policies_equal(dummy_policy, &ci->ci_policy)) {
-                       struct fscrypt_dummy_policy tmp = { dummy_policy };
-
-                       err = fscrypt_add_test_dummy_key(sb, &tmp);
+                       err = fscrypt_add_test_dummy_key(sb, &mk_spec);
                        if (err)
                                return err;
                        mk = fscrypt_find_master_key(sb, &mk_spec);

diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 4f5f8a6..44848d8 100644 (file)
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -309,8 +309,6 @@ fscrypt_free_dummy_policy(struct fscrypt_dummy_policy *dummy_policy)
 /* keyring.c */
 void fscrypt_destroy_keyring(struct super_block *sb);
 int fscrypt_ioctl_add_key(struct file *filp, void __user *arg);
-int fscrypt_add_test_dummy_key(struct super_block *sb,
-                              const struct fscrypt_dummy_policy *dummy_policy);
 int fscrypt_ioctl_remove_key(struct file *filp, void __user *arg);
 int fscrypt_ioctl_remove_key_all_users(struct file *filp, void __user *arg);
 int fscrypt_ioctl_get_key_status(struct file *filp, void __user *arg);
@@ -530,13 +528,6 @@ static inline int fscrypt_ioctl_add_key(struct file *filp, void __user *arg)
        return -EOPNOTSUPP;
 }
 
-static inline int
-fscrypt_add_test_dummy_key(struct super_block *sb,
-                          const struct fscrypt_dummy_policy *dummy_policy)
-{
-       return 0;
-}
-
 static inline int fscrypt_ioctl_remove_key(struct file *filp, void __user *arg)
 {
        return -EOPNOTSUPP;