[PATCH v4 09/46] btrfs: disable various operations on encrypted inodes

Josef Bacik
2023-12-01T22:12:08Z

From: Omar Sandoval <osandov@osandov.com>

Initially, only normal data extents will be encrypted. This change
forbids various other bits:
- allows reflinking only if both inodes have the same encryption status
- disable inline data on encrypted inodes

Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
fs/btrfs/inode.c | 3 ++-
fs/btrfs/reflink.c | 7 +++++++
2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index f8647d8271b7..108804a5ba82 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -639,7 +639,8 @@ static noinline int cow_file_range_inline(struct btrfs_inode *inode, u64 size,
* compressed) data fits in a leaf and the configured maximum inline
* size.
*/
- if (size < i_size_read(&inode->vfs_inode) ||
+ if (IS_ENCRYPTED(&inode->vfs_inode) ||
+ size < i_size_read(&inode->vfs_inode) ||
size > fs_info->sectorsize ||
data_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info) ||
data_len > fs_info->max_inline)
diff --git a/fs/btrfs/reflink.c b/fs/btrfs/reflink.c
index f88b0c2ac3fe..c39de2a43a00 100644
--- a/fs/btrfs/reflink.c
+++ b/fs/btrfs/reflink.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0

#include <linux/blkdev.h>
+#include <linux/fscrypt.h>
#include <linux/iversion.h>
#include "ctree.h"
#include "fs.h"
@@ -809,6 +810,12 @@ static int btrfs_remap_file_range_prep(struct file *file_in, loff_t pos_in,
ASSERT(inode_in->i_sb == inode_out->i_sb);
}

+ /*
+ * Can only reflink encrypted files if both files are encrypted.
+ */
+ if (IS_ENCRYPTED(inode_in) != IS_ENCRYPTED(inode_out))
+ return -EINVAL;
+
/* Don't make the dst file partly checksummed */
if ((BTRFS_I(inode_in)->flags & BTRFS_INODE_NODATASUM) !=
(BTRFS_I(inode_out)->flags & BTRFS_INODE_NODATASUM)) {
--
2.41.0