[PATCH 5.4 38/51] xfs: fix misuse of the XFS_ATTR_INCOMPLETE flag

From: Greg Kroah-Hartman
Date: Wed Oct 05 2022 - 07:36:38 EST


From: Christoph Hellwig <hch@xxxxxx>

commit 780d29057781d986cd87dbbe232cd02876ad430f upstream.

XFS_ATTR_INCOMPLETE is a flag in the on-disk attribute format, and thus
in a different namespace as the ATTR_* flags in xfs_da_args.flags.
Switch to using a XFS_DA_OP_INCOMPLETE flag in op_flags instead. Without
this users might be able to inject this flag into operations using the
attr by handle ioctl.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Acked-by: Darrick J. Wong <djwong@xxxxxxxxxx>
Signed-off-by: Chandan Babu R <chandan.babu@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/xfs/libxfs/xfs_attr.c | 2 +-
fs/xfs/libxfs/xfs_attr_leaf.c | 4 ++--
fs/xfs/libxfs/xfs_da_btree.h | 4 +++-
fs/xfs/libxfs/xfs_da_format.h | 2 --
4 files changed, 6 insertions(+), 6 deletions(-)

--- a/fs/xfs/libxfs/xfs_attr.c
+++ b/fs/xfs/libxfs/xfs_attr.c
@@ -1007,7 +1007,7 @@ restart:
* The INCOMPLETE flag means that we will find the "old"
* attr, not the "new" one.
*/
- args->flags |= XFS_ATTR_INCOMPLETE;
+ args->op_flags |= XFS_DA_OP_INCOMPLETE;
state = xfs_da_state_alloc();
state->args = args;
state->mp = mp;
--- a/fs/xfs/libxfs/xfs_attr_leaf.c
+++ b/fs/xfs/libxfs/xfs_attr_leaf.c
@@ -2345,8 +2345,8 @@ xfs_attr3_leaf_lookup_int(
* If we are looking for INCOMPLETE entries, show only those.
* If we are looking for complete entries, show only those.
*/
- if ((args->flags & XFS_ATTR_INCOMPLETE) !=
- (entry->flags & XFS_ATTR_INCOMPLETE)) {
+ if (!!(args->op_flags & XFS_DA_OP_INCOMPLETE) !=
+ !!(entry->flags & XFS_ATTR_INCOMPLETE)) {
continue;
}
if (entry->flags & XFS_ATTR_LOCAL) {
--- a/fs/xfs/libxfs/xfs_da_btree.h
+++ b/fs/xfs/libxfs/xfs_da_btree.h
@@ -82,6 +82,7 @@ typedef struct xfs_da_args {
#define XFS_DA_OP_OKNOENT 0x0008 /* lookup/add op, ENOENT ok, else die */
#define XFS_DA_OP_CILOOKUP 0x0010 /* lookup to return CI name if found */
#define XFS_DA_OP_ALLOCVAL 0x0020 /* lookup to alloc buffer if found */
+#define XFS_DA_OP_INCOMPLETE 0x0040 /* lookup INCOMPLETE attr keys */

#define XFS_DA_OP_FLAGS \
{ XFS_DA_OP_JUSTCHECK, "JUSTCHECK" }, \
@@ -89,7 +90,8 @@ typedef struct xfs_da_args {
{ XFS_DA_OP_ADDNAME, "ADDNAME" }, \
{ XFS_DA_OP_OKNOENT, "OKNOENT" }, \
{ XFS_DA_OP_CILOOKUP, "CILOOKUP" }, \
- { XFS_DA_OP_ALLOCVAL, "ALLOCVAL" }
+ { XFS_DA_OP_ALLOCVAL, "ALLOCVAL" }, \
+ { XFS_DA_OP_INCOMPLETE, "INCOMPLETE" }

/*
* Storage for holding state during Btree searches and split/join ops.
--- a/fs/xfs/libxfs/xfs_da_format.h
+++ b/fs/xfs/libxfs/xfs_da_format.h
@@ -740,8 +740,6 @@ struct xfs_attr3_icleaf_hdr {

/*
* Flags used in the leaf_entry[i].flags field.
- * NOTE: the INCOMPLETE bit must not collide with the flags bits specified
- * on the system call, they are "or"ed together for various operations.
*/
#define XFS_ATTR_LOCAL_BIT 0 /* attr is stored locally */
#define XFS_ATTR_ROOT_BIT 1 /* limit access to trusted attrs */