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, 22 insertions, 0 deletions

diff --git a/drivers/media/common/ttpci-eeprom.h b/drivers/media/common/ttpci-eeprom.h
new file mode 100644
index 000000000..ee741867b
--- /dev/null
+++ b/drivers/media/common/ttpci-eeprom.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+    Retrieve encoded MAC address from ATMEL ttpci_eeprom serial 2-wire EEPROM,
+    decode it and store it in associated adapter net device
+
+    Robert Schlabbach	GMX
+    Michael Glaum	KVH Industries
+    Holger Waechtler	Convergence
+
+
+*/
+
+#ifndef __TTPCI_EEPROM_H__
+#define __TTPCI_EEPROM_H__
+
+#include <linux/types.h>
+#include <linux/i2c.h>
+
+extern int ttpci_eeprom_decode_mac(u8 *decodedMAC, u8 *encodedMAC);
+extern int ttpci_eeprom_parse_mac(struct i2c_adapter *adapter, u8 *propsed_mac);
+
+#endif