kernel.git/fs/crypto/policy.c, branch linux-4.7.y

fscrypto: only allow setting encryption policy on directories

2016-09-15T06:20:29Z

commit 002ced4be6429918800ce3e41d5cbc2d7c01822c upstream. The FS_IOC_SET_ENCRYPTION_POLICY ioctl allowed setting an encryption policy on nondirectory files. This was unintentional, and in the case of nonempty regular files did not behave as expected because existing data was not actually encrypted by the ioctl. In the case of ext4, the user could also trigger filesystem errors in ->empty_dir(), e.g. due to mismatched "directory" checksums when the kernel incorrectly tried to interpret a regular file as a directory. This bug affected ext4 with kernels v4.8-rc1 or later and f2fs with kernels v4.6 and later. It appears that older kernels only permitted directories and that the check was accidentally lost during the refactoring to share the file encryption code between ext4 and f2fs. This patch restores the !S_ISDIR() check that was present in older kernels. Signed-off-by: Eric Biggers Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

fscrypto: add authorization check for setting encryption policy

2016-09-15T06:20:29Z

commit 163ae1c6ad6299b19e22b4a35d5ab24a89791a98 upstream. On an ext4 or f2fs filesystem with file encryption supported, a user could set an encryption policy on any empty directory(*) to which they had readonly access. This is obviously problematic, since such a directory might be owned by another user and the new encryption policy would prevent that other user from creating files in their own directory (for example). Fix this by requiring inode_owner_or_capable() permission to set an encryption policy. This means that either the caller must own the file, or the caller must have the capability CAP_FOWNER. (*) Or also on any regular file, for f2fs v4.6 and later and ext4 v4.8-rc1 and later; a separate bug fix is coming for that. Signed-off-by: Eric Biggers Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

fs crypto: move per-file encryption from f2fs tree to fs/crypto

2016-03-18T04:19:33Z

This patch adds the renamed functions moved from the f2fs crypto files. 1. definitions for per-file encryption used by ext4 and f2fs. 2. crypto.c for encrypt/decrypt functions a. IO preparation: - fscrypt_get_ctx / fscrypt_release_ctx b. before IOs: - fscrypt_encrypt_page - fscrypt_decrypt_page - fscrypt_zeroout_range c. after IOs: - fscrypt_decrypt_bio_pages - fscrypt_pullback_bio_page - fscrypt_restore_control_page 3. policy.c supporting context management. a. For ioctls: - fscrypt_process_policy - fscrypt_get_policy b. For context permission - fscrypt_has_permitted_context - fscrypt_inherit_context 4. keyinfo.c to handle permissions - fscrypt_get_encryption_info - fscrypt_free_encryption_info 5. fname.c to support filename encryption a. general wrapper functions - fscrypt_fname_disk_to_usr - fscrypt_fname_usr_to_disk - fscrypt_setup_filename - fscrypt_free_filename b. specific filename handling functions - fscrypt_fname_alloc_buffer - fscrypt_fname_free_buffer 6. Makefile and Kconfig Cc: Al Viro Signed-off-by: Michael Halcrow Signed-off-by: Ildar Muslukhov Signed-off-by: Uday Savagaonkar Signed-off-by: Theodore Ts'o Signed-off-by: Arnd Bergmann Signed-off-by: Jaegeuk Kim