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, 25 insertions, 0 deletions

diff --git a/drivers/scsi/mvme147.h b/drivers/scsi/mvme147.h
new file mode 100644
index 000000000..f75ff58dd
--- /dev/null
+++ b/drivers/scsi/mvme147.h
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef MVME147_H
+
+/* $Id: mvme147.h,v 1.4 1997/01/19 23:07:10 davem Exp $
+ *
+ * Header file for the MVME147 built-in SCSI controller for Linux
+ *
+ * Written and (C) 1993, Hamish Macdonald, see mvme147.c for more info
+ *
+ */
+
+#include <linux/types.h>
+
+int mvme147_detect(struct scsi_host_template *);
+int mvme147_release(struct Scsi_Host *);
+
+#ifndef CMD_PER_LUN
+#define CMD_PER_LUN		2
+#endif
+
+#ifndef CAN_QUEUE
+#define CAN_QUEUE		16
+#endif
+
+#endif /* MVME147_H */