On Wed, Dec 02, 2020 at 06:20:32PM -0800, Eric Biggers wrote: > Currently it's impossible to delete files that use an unsupported > encryption policy, as the kernel will just return an error when > performing any operation on the top-level encrypted directory, even just > a path lookup into the directory or opening the directory for readdir. > > It's desirable to return errors for most operations on files that use an > unsupported encryption policy, but the current behavior is too strict. > We need to allow enough to delete files, so that people can't be stuck > with undeletable files when downgrading kernel versions. That includes > allowing directories to be listed and allowing dentries to be looked up. > > This series fixes this (on ext4, f2fs, and ubifs) by treating an > unsupported encryption policy in the same way as "key unavailable" in > the cases that are required for a recursive delete to work. > > The actual fix is in patch 9, so see that for more details. > > Patches 1-8 are cleanups that prepare for the actual fix by removing > direct use of fscrypt_get_encryption_info() by filesystems. > > This patchset applies to branch "master" (commit 4a4b8721f1a5) of > https://git.kernel.org/pub/scm/fs/fscrypt/fscrypt.git. > > Changed since v1: > - Made some minor updates to commit messages. > - Added Reviewed-by tags. > > Eric Biggers (9): > ext4: remove ext4_dir_open() > f2fs: remove f2fs_dir_open() > ubifs: remove ubifs_dir_open() > ext4: don't call fscrypt_get_encryption_info() from dx_show_leaf() > fscrypt: introduce fscrypt_prepare_readdir() > fscrypt: move body of fscrypt_prepare_setattr() out-of-line > fscrypt: move fscrypt_require_key() to fscrypt_private.h > fscrypt: unexport fscrypt_get_encryption_info() > fscrypt: allow deleting files with unsupported encryption policy > > fs/crypto/fname.c | 8 +++- > fs/crypto/fscrypt_private.h | 28 ++++++++++++++ > fs/crypto/hooks.c | 16 +++++++- > fs/crypto/keysetup.c | 20 ++++++++-- > fs/crypto/policy.c | 22 +++++++---- > fs/ext4/dir.c | 16 ++------ > fs/ext4/namei.c | 10 +---- > fs/f2fs/dir.c | 10 +---- > fs/ubifs/dir.c | 11 +----- > include/linux/fscrypt.h | 75 +++++++++++++++++++------------------ > 10 files changed, 126 insertions(+), 90 deletions(-) > > > base-commit: 4a4b8721f1a5e4b01e45b3153c68d5a1014b25de All applied to fscrypt.git#master for 5.11. - Eric
