Commit f18f9845 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linux 

Pull fscrypt updates from Eric Biggers:
 "Simplify the implementation of the test_dummy_encryption mount option
  by adding the 'test dummy key' on-demand"

* tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linux:
  fscrypt: clean up fscrypt_add_test_dummy_key()
  fs/super.c: stop calling fscrypt_destroy_keyring() from __put_super()
  f2fs: stop calling fscrypt_add_test_dummy_key()
  ext4: stop calling fscrypt_add_test_dummy_key()
  fscrypt: add the test dummy encryption key on-demand
parents dc483c85 097d7c1f

fs/crypto/fscrypt_private.h

+4 −0
Original line number Diff line number Diff line
@@ -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]);
@@ -651,6 +654,7 @@ bool fscrypt_policies_equal(const union fscrypt_policy *policy1, 
			    const union fscrypt_policy *policy2);

int fscrypt_policy_to_key_spec(const union fscrypt_policy *policy,

			       struct fscrypt_key_specifier *key_spec);

const union fscrypt_policy *fscrypt_get_dummy_policy(struct super_block *sb);

bool fscrypt_supported_policy(const union fscrypt_policy *policy_u,

			      const struct inode *inode);

int fscrypt_policy_from_context(union fscrypt_policy *policy_u,

fs/crypto/keyring.c

+7 −19
Original line number Diff line number Diff line
@@ -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 @@ int fscrypt_get_test_dummy_key_identifier( 
/**

 * 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

fs/crypto/keysetup.c

+21 −2
Original line number Diff line number Diff line
@@ -438,6 +438,7 @@ static int setup_file_encryption_key(struct fscrypt_info *ci, 
				     bool need_dirhash_key,

				     struct fscrypt_master_key **mk_ret)

{

	struct super_block *sb = ci->ci_inode->i_sb;

	struct fscrypt_key_specifier mk_spec;

	struct fscrypt_master_key *mk;

	int err;
@@ -450,8 +451,26 @@ static int setup_file_encryption_key(struct fscrypt_info *ci, 
	if (err)

		return err;



	mk = fscrypt_find_master_key(ci->ci_inode->i_sb, &mk_spec);

	if (!mk) {

	mk = fscrypt_find_master_key(sb, &mk_spec);

	if (unlikely(!mk)) {

		const union fscrypt_policy *dummy_policy =

			fscrypt_get_dummy_policy(sb);



		/*

		 * Add the test_dummy_encryption key on-demand.  In principle,

		 * it should be added at mount time.  Do it here instead so that

		 * the individual filesystems don't need to worry about adding

		 * this key at mount time and cleaning up on mount failure.

		 */

		if (dummy_policy &&

		    fscrypt_policies_equal(dummy_policy, &ci->ci_policy)) {

			err = fscrypt_add_test_dummy_key(sb, &mk_spec);

			if (err)

				return err;

			mk = fscrypt_find_master_key(sb, &mk_spec);

		}

	}

	if (unlikely(!mk)) {

		if (ci->ci_policy.version != FSCRYPT_POLICY_V1)

			return -ENOKEY;

fs/crypto/policy.c

+1 −2
Original line number Diff line number Diff line
@@ -53,8 +53,7 @@ int fscrypt_policy_to_key_spec(const union fscrypt_policy *policy, 
	}

}



static const union fscrypt_policy *

fscrypt_get_dummy_policy(struct super_block *sb)

const union fscrypt_policy *fscrypt_get_dummy_policy(struct super_block *sb)

{

	if (!sb->s_cop->get_dummy_policy)

		return NULL;

fs/ext4/super.c

+1 −12
Original line number Diff line number Diff line
@@ -2635,7 +2635,6 @@ static int ext4_check_test_dummy_encryption(const struct fs_context *fc, 
{

	const struct ext4_fs_context *ctx = fc->fs_private;

	const struct ext4_sb_info *sbi = EXT4_SB(sb);

	int err;



	if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy))

		return 0;
@@ -2668,17 +2667,7 @@ static int ext4_check_test_dummy_encryption(const struct fs_context *fc, 
			 "Conflicting test_dummy_encryption options");

		return -EINVAL;

	}

	/*

	 * fscrypt_add_test_dummy_key() technically changes the super_block, so

	 * technically it should be delayed until ext4_apply_options() like the

	 * other changes.  But since we never get here for remounts (see above),

	 * and this is the last chance to report errors, we do it here.

	 */

	err = fscrypt_add_test_dummy_key(sb, &ctx->dummy_enc_policy);

	if (err)

		ext4_msg(NULL, KERN_WARNING,

			 "Error adding test dummy encryption key [%d]", err);

	return err;

	return 0;

}



static void ext4_apply_test_dummy_encryption(struct ext4_fs_context *ctx,