selftests/bpf: Reject graph kptr use after RCU unlockgrafted

Add a sleepable verifier test that loads a graph-node local kptr in an
explicit RCU read-side critical section, then passes its node to
bpf_rbtree_remove() after the section ends.

Before the verifier fix, the stale NON_OWN_REF flag makes the node look like
a live borrowed reference and the program is accepted. After the fix, the
pointer is demoted without NON_OWN_REF and the graph kfunc argument is
rejected.

Also exercise a graph kptr loaded while a spin lock provides implicit RCU
protection. The pointer must be invalidated when the lock is released, which
guards the required ordering between non-owning-reference invalidation and
RCU demotion.

Update the existing fault-protected load test state description. The
post-unlock pointer no longer carries NON_OWN_REF, but remains readable
because the load is rewritten to use BPF_PROBE_MEM.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 24 insertions, 0 deletions

diff --git a/fs/ntfs/reparse.h b/fs/ntfs/reparse.h
new file mode 100644
index 000000000..c11a5bb7e
--- /dev/null
+++ b/fs/ntfs/reparse.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (c) 2008-2021 Jean-Pierre Andre
+ * Copyright (c) 2025 LG Electronics Co., Ltd.
+ */
+
+#ifndef _LINUX_NTFS_REPARSE_H
+#define _LINUX_NTFS_REPARSE_H
+
+extern __le16 reparse_index_name[];
+
+unsigned int ntfs_make_symlink(struct ntfs_inode *ni);
+unsigned int ntfs_reparse_tag_dt_types(struct ntfs_volume *vol, unsigned long mref);
+int ntfs_translate_symlink_path(struct dentry *dentry, const char *target,
+				char **translated);
+int ntfs_reparse_set_wsl_symlink(struct ntfs_inode *ni,
+				 const char *target, int target_len);
+int ntfs_reparse_set_native_symlink(struct ntfs_inode *ni,
+				    const char *symname, int symlen);
+int ntfs_reparse_set_wsl_not_symlink(struct ntfs_inode *ni, mode_t mode);
+int ntfs_delete_reparse_index(struct ntfs_inode *ni);
+int ntfs_remove_ntfs_reparse_data(struct ntfs_inode *ni);
+
+#endif /* _LINUX_NTFS_REPARSE_H */