Encryption is currently only supported on files/directories with layouts where stripe_count=1. Forbid changing layouts when encryption is involved. Signed-off-by: Luis Henriques <lhenriques@xxxxxxx> --- Hi! While continuing looking into fscrypt, I realized we're not yet forbidding different layouts on encrypted files. This patch tries to do just that. Regarding the setxattr, I've also made a change [1] to the MDS code so that it also prevents layouts to be changed. This should make the changes to ceph_sync_setxattr() redundant, but in practice it doesn't because if we encrypt a directory and immediately after that we change that directory layout, the MDS wouldn't yet have received the fscrypt_auth for that inode. So... yeah, an alternative would be to propagate the fscrypt context immediately after encrypting a directory. [1] https://github.com/luis-henrix/ceph/commit/601488ae798ecfa5ec81677d1ced02f7dd42aa10 Cheers, -- Luis fs/ceph/ioctl.c | 4 ++++ fs/ceph/xattr.c | 6 ++++++ 2 files changed, 10 insertions(+) diff --git a/fs/ceph/ioctl.c b/fs/ceph/ioctl.c index 477ecc667aee..42abfc564301 100644 --- a/fs/ceph/ioctl.c +++ b/fs/ceph/ioctl.c @@ -294,6 +294,10 @@ static long ceph_set_encryption_policy(struct file *file, unsigned long arg) struct inode *inode = file_inode(file); struct ceph_inode_info *ci = ceph_inode(inode); + /* encrypted directories can't have striped layout */ + if (ci->i_layout.stripe_count > 1) + return -EOPNOTSUPP; + ret = vet_mds_for_fscrypt(file); if (ret) return ret; diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c index b175b3029dc0..7921cb34900c 100644 --- a/fs/ceph/xattr.c +++ b/fs/ceph/xattr.c @@ -1051,6 +1051,12 @@ static int ceph_sync_setxattr(struct inode *inode, const char *name, int op = CEPH_MDS_OP_SETXATTR; int err; + /* encrypted directories/files can't have their layout changed */ + if (IS_ENCRYPTED(inode) && + (!strncmp(name, "ceph.file.layout", 16) || + !strncmp(name, "ceph.dir.layout", 15))) + return -EOPNOTSUPP; + if (size > 0) { /* copy value into pagelist */ pagelist = ceph_pagelist_alloc(GFP_NOFS); Cheers, -- Luís
