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, 18 insertions, 0 deletions

diff --git a/include/dt-bindings/input/input.h b/include/dt-bindings/input/input.h
new file mode 100644
index 000000000..bcf0ae100
--- /dev/null
+++ b/include/dt-bindings/input/input.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This header provides constants for most input bindings.
+ *
+ * Most input bindings include key code, matrix key code format.
+ * In most cases, key code and matrix key code format uses
+ * the standard values/macro defined in this header.
+ */
+
+#ifndef _DT_BINDINGS_INPUT_INPUT_H
+#define _DT_BINDINGS_INPUT_INPUT_H
+
+#include "linux-event-codes.h"
+
+#define MATRIX_KEY(row, col, code)	\
+	((((row) & 0xFF) << 24) | (((col) & 0xFF) << 16) | ((code) & 0xFFFF))
+
+#endif /* _DT_BINDINGS_INPUT_INPUT_H */