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, 59 insertions, 0 deletions

diff --git a/drivers/soc/apple/rtkit-internal.h b/drivers/soc/apple/rtkit-internal.h
new file mode 100644
index 000000000..b8d524467
--- /dev/null
+++ b/drivers/soc/apple/rtkit-internal.h
@@ -0,0 +1,59 @@
+/* SPDX-License-Identifier: GPL-2.0-only OR MIT */
+/*
+ * Apple RTKit IPC library
+ * Copyright (C) The Asahi Linux Contributors
+ */
+
+#ifndef _APPLE_RTKIT_INTERAL_H
+#define _APPLE_RTKIT_INTERAL_H
+
+#include <linux/bitfield.h>
+#include <linux/bitmap.h>
+#include <linux/completion.h>
+#include <linux/dma-mapping.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/soc/apple/rtkit.h>
+#include <linux/workqueue.h>
+#include "mailbox.h"
+
+#define APPLE_RTKIT_APP_ENDPOINT_START 0x20
+#define APPLE_RTKIT_MAX_ENDPOINTS 0x100
+
+struct apple_rtkit {
+	void *cookie;
+	const struct apple_rtkit_ops *ops;
+	struct device *dev;
+
+	struct apple_mbox *mbox;
+
+	struct completion epmap_completion;
+	struct completion iop_pwr_ack_completion;
+	struct completion ap_pwr_ack_completion;
+
+	int boot_result;
+	int version;
+
+	unsigned int iop_power_state;
+	unsigned int ap_power_state;
+	bool crashed;
+
+	DECLARE_BITMAP(endpoints, APPLE_RTKIT_MAX_ENDPOINTS);
+
+	struct apple_rtkit_shmem ioreport_buffer;
+	struct apple_rtkit_shmem crashlog_buffer;
+	struct apple_rtkit_shmem oslog_buffer;
+
+	struct apple_rtkit_shmem syslog_buffer;
+	char *syslog_msg_buffer;
+	size_t syslog_n_entries;
+	size_t syslog_msg_size;
+
+	struct workqueue_struct *wq;
+};
+
+void apple_rtkit_crashlog_dump(struct apple_rtkit *rtk, u8 *bfr, size_t size);
+
+#endif