The Merkle tree blocks and descriptor are stored in the extended
attributes of the inode. Add new attribute type for fs-verity
metadata. Add XFS_ATTR_INTERNAL_MASK to skip parent pointer and
fs-verity attributes as those are only for internal use. While we're
at it add a few comments in relevant places that internally visible
attributes are not suppose to be handled via interface defined in
xfs_xattr.c.
Signed-off-by: Andrey Albershteyn <aalbersh@xxxxxxxxxx>
---
fs/xfs/libxfs/xfs_da_format.h | 10 +++++++++-
fs/xfs/libxfs/xfs_log_format.h | 1 +
fs/xfs/xfs_ioctl.c | 5 +++++
fs/xfs/xfs_trace.h | 1 +
fs/xfs/xfs_xattr.c | 9 +++++++++
5 files changed, 25 insertions(+), 1 deletion(-)
diff --git a/fs/xfs/libxfs/xfs_da_format.h b/fs/xfs/libxfs/xfs_da_format.h
index 6deefe03207f..b56bdae83563 100644
--- a/fs/xfs/libxfs/xfs_da_format.h
+++ b/fs/xfs/libxfs/xfs_da_format.h
@@ -699,14 +699,22 @@ struct xfs_attr3_leafblock {
#define XFS_ATTR_ROOT_BIT 1 /* limit access to trusted attrs */
#define XFS_ATTR_SECURE_BIT 2 /* limit access to secure attrs */
#define XFS_ATTR_PARENT_BIT 3 /* parent pointer attrs */
+#define XFS_ATTR_VERITY_BIT 4 /* verity merkle tree and descriptor */
#define XFS_ATTR_INCOMPLETE_BIT 7 /* attr in middle of create/delete */
#define XFS_ATTR_LOCAL (1u << XFS_ATTR_LOCAL_BIT)
#define XFS_ATTR_ROOT (1u << XFS_ATTR_ROOT_BIT)
#define XFS_ATTR_SECURE (1u << XFS_ATTR_SECURE_BIT)
#define XFS_ATTR_PARENT (1u << XFS_ATTR_PARENT_BIT)
+#define XFS_ATTR_VERITY (1u << XFS_ATTR_VERITY_BIT)
#define XFS_ATTR_INCOMPLETE (1u << XFS_ATTR_INCOMPLETE_BIT)
#define XFS_ATTR_NSP_ONDISK_MASK \
- (XFS_ATTR_ROOT | XFS_ATTR_SECURE | XFS_ATTR_PARENT)
+ (XFS_ATTR_ROOT | XFS_ATTR_SECURE | XFS_ATTR_PARENT | \
+ XFS_ATTR_VERITY)
+
+/*
+ * Internal attributes not exposed to the user
+ */
+#define XFS_ATTR_INTERNAL_MASK (XFS_ATTR_PARENT | XFS_ATTR_VERITY)
/*
* Alignment for namelist and valuelist entries (since they are mixed
diff --git a/fs/xfs/libxfs/xfs_log_format.h b/fs/xfs/libxfs/xfs_log_format.h
index 0bc1749fb7bb..c42cc58cd152 100644
--- a/fs/xfs/libxfs/xfs_log_format.h
+++ b/fs/xfs/libxfs/xfs_log_format.h
@@ -975,6 +975,7 @@ struct xfs_icreate_log {
#define XFS_ATTRI_FILTER_MASK (XFS_ATTR_ROOT | \
XFS_ATTR_SECURE | \
XFS_ATTR_PARENT | \
+ XFS_ATTR_VERITY | \
XFS_ATTR_INCOMPLETE)
/*
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 55bb01173cde..3d6d680b6cf3 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -351,6 +351,11 @@ static unsigned int
xfs_attr_filter(
u32 ioc_flags)
{
+ /*
+ * Only externally visible attributes should be specified here.
+ * Internally used attributes (such as parent pointers or fs-verity)
+ * should not be exposed to userspace.
+ */
if (ioc_flags & XFS_IOC_ATTR_ROOT)
return XFS_ATTR_ROOT;
if (ioc_flags & XFS_IOC_ATTR_SECURE)
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index 3926cf7f2a6e..3696709907bf 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -82,6 +82,7 @@ struct xfs_perag;
#define XFS_ATTR_FILTER_FLAGS \
{ XFS_ATTR_ROOT, "ROOT" }, \
{ XFS_ATTR_SECURE, "SECURE" }, \
+ { XFS_ATTR_VERITY, "VERITY" }, \
{ XFS_ATTR_INCOMPLETE, "INCOMPLETE" }
DECLARE_EVENT_CLASS(xfs_attr_list_class,
diff --git a/fs/xfs/xfs_xattr.c b/fs/xfs/xfs_xattr.c
index a3975f325f4e..56f7f4122fcb 100644
--- a/fs/xfs/xfs_xattr.c
+++ b/fs/xfs/xfs_xattr.c
@@ -20,6 +20,12 @@
#include <linux/posix_acl_xattr.h>
+/*
+ * This file defines interface to work with externally visible extended
+ * attributes, such as those in system or security namespaces. This interface
+ * should not be used for internally used attributes (consider xfs_attr.c).
+ */
+
/*
* Get permission to use log-assisted atomic exchange of file extents.
*
@@ -241,6 +247,9 @@ xfs_xattr_put_listent(
ASSERT(context->count >= 0);
+ if (flags & XFS_ATTR_INTERNAL_MASK)
+ return;
+
if (flags & XFS_ATTR_ROOT) {
#ifdef CONFIG_XFS_POSIX_ACL
if (namelen == SGI_ACL_FILE_SIZE &&
--
2.40.1
