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, 88 insertions, 0 deletions

diff --git a/scripts/kconfig/nconf.h b/scripts/kconfig/nconf.h
new file mode 100644
index 000000000..ab836d582
--- /dev/null
+++ b/scripts/kconfig/nconf.h
@@ -0,0 +1,88 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2008 Nir Tzachar <nir.tzachar@gmail.com>
+ *
+ * Derived from menuconfig.
+ */
+
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <ncurses.h>
+#include <menu.h>
+#include <panel.h>
+#include <form.h>
+
+#include <stdio.h>
+#include <time.h>
+#include <sys/time.h>
+
+#define max(a, b) ({\
+		typeof(a) _a = a;\
+		typeof(b) _b = b;\
+		_a > _b ? _a : _b; })
+
+#define min(a, b) ({\
+		typeof(a) _a = a;\
+		typeof(b) _b = b;\
+		_a < _b ? _a : _b; })
+
+extern int attr_normal;
+extern int attr_main_heading;
+extern int attr_main_menu_box;
+extern int attr_main_menu_fore;
+extern int attr_main_menu_back;
+extern int attr_main_menu_grey;
+extern int attr_main_menu_heading;
+extern int attr_scrollwin_text;
+extern int attr_scrollwin_heading;
+extern int attr_scrollwin_box;
+extern int attr_dialog_text;
+extern int attr_dialog_menu_fore;
+extern int attr_dialog_menu_back;
+extern int attr_dialog_box;
+extern int attr_input_box;
+extern int attr_input_heading;
+extern int attr_input_text;
+extern int attr_input_field;
+extern int attr_function_text;
+extern int attr_function_highlight;
+
+typedef enum {
+	F_HELP = 1,
+	F_SYMBOL = 2,
+	F_INSTS = 3,
+	F_CONF = 4,
+	F_BACK = 5,
+	F_SAVE = 6,
+	F_LOAD = 7,
+	F_SEARCH = 8,
+	F_EXIT = 9,
+} function_key;
+
+void set_colors(void);
+
+typedef int (*extra_key_cb_fn)(int, size_t, size_t, void *);
+
+/* this changes the windows attributes !!! */
+void print_in_middle(WINDOW *win, int y, int width, const char *str, int attrs);
+int get_line_length(const char *line);
+int get_line_no(const char *text);
+const char *get_line(const char *text, int line_no);
+void fill_window(WINDOW *win, const char *text);
+int btn_dialog(WINDOW *main_window, const char *msg, int btn_num, ...);
+int dialog_inputbox(WINDOW *main_window,
+		const char *title, const char *prompt,
+		const char *init, char **resultp, int *result_len);
+void refresh_all_windows(WINDOW *main_window);
+int show_scroll_win_ext(WINDOW *main_window, const char *title, char *text,
+			int *vscroll, int *hscroll,
+			extra_key_cb_fn extra_key_cb, void *data);
+void show_scroll_win(WINDOW *main_window,
+		const char *title,
+		const char *text);