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, 31 insertions, 0 deletions

diff --git a/drivers/clk/qcom/reset.h b/drivers/clk/qcom/reset.h
new file mode 100644
index 000000000..fe0561bf5
--- /dev/null
+++ b/drivers/clk/qcom/reset.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2013, The Linux Foundation. All rights reserved.
+ */
+
+#ifndef __QCOM_CLK_RESET_H__
+#define __QCOM_CLK_RESET_H__
+
+#include <linux/reset-controller.h>
+
+struct qcom_reset_map {
+	unsigned int reg;
+	u8 bit;
+	u16 udelay;
+	u32 bitmask;
+};
+
+struct regmap;
+
+struct qcom_reset_controller {
+	const struct qcom_reset_map *reset_map;
+	struct regmap *regmap;
+	struct reset_controller_dev rcdev;
+};
+
+#define to_qcom_reset_controller(r) \
+	container_of(r, struct qcom_reset_controller, rcdev);
+
+extern const struct reset_control_ops qcom_reset_ops;
+
+#endif