From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Check extended attribute entry names for invalid characters.
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
---
fs/xfs/libxfs/xfs_attr.c | 17 +++++++++++++++++
fs/xfs/libxfs/xfs_attr.h | 2 +-
fs/xfs/scrub/attr.c | 6 ++++++
3 files changed, 24 insertions(+), 1 deletion(-)
diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
index 844ed87b1900..2dd9ee2a2e08 100644
--- a/fs/xfs/libxfs/xfs_attr.c
+++ b/fs/xfs/libxfs/xfs_attr.c
@@ -1336,3 +1336,20 @@ xfs_attr_node_get(xfs_da_args_t *args)
xfs_da_state_free(state);
return retval;
}
+
+/* Returns true if the attribute entry name is valid. */
+bool
+xfs_attr_namecheck(
+ const void *name,
+ size_t length)
+{
+ /*
+ * MAXNAMELEN includes the trailing null, but (name/length) leave it
+ * out, so use >= for the length check.
+ */
+ if (length >= MAXNAMELEN)
+ return false;
+
+ /* There shouldn't be any nulls here */
+ return !memchr(name, 0, length);
+}
diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h
index bdf52a333f3f..2297d8467666 100644
--- a/fs/xfs/libxfs/xfs_attr.h
+++ b/fs/xfs/libxfs/xfs_attr.h
@@ -145,6 +145,6 @@ int xfs_attr_remove(struct xfs_inode *dp, const unsigned char *name, int flags);
int xfs_attr_remove_args(struct xfs_da_args *args);
int xfs_attr_list(struct xfs_inode *dp, char *buffer, int bufsize,
int flags, struct attrlist_cursor_kern *cursor);
-
+bool xfs_attr_namecheck(const void *name, size_t length);
#endif /* __XFS_ATTR_H__ */
diff --git a/fs/xfs/scrub/attr.c b/fs/xfs/scrub/attr.c
index 9960bc5b5d76..dce74ec57038 100644
--- a/fs/xfs/scrub/attr.c
+++ b/fs/xfs/scrub/attr.c
@@ -93,6 +93,12 @@ xchk_xattr_listent(
return;
}
+ /* Does this name make sense? */
+ if (!xfs_attr_namecheck(name, namelen)) {
+ xchk_fblock_set_corrupt(sx->sc, XFS_ATTR_FORK, args.blkno);
+ return;
+ }
+
args.flags = ATTR_KERNOTIME;
if (flags & XFS_ATTR_ROOT)
args.flags |= ATTR_ROOT;
