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, 39 insertions, 0 deletions

diff --git a/include/crypto/cryptd.h b/include/crypto/cryptd.h
new file mode 100644
index 000000000..29c5878a3
--- /dev/null
+++ b/include/crypto/cryptd.h
@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Software async crypto daemon
+ *
+ * Added AEAD support to cryptd.
+ *    Authors: Tadeusz Struk (tadeusz.struk@intel.com)
+ *             Adrian Hoban <adrian.hoban@intel.com>
+ *             Gabriele Paoloni <gabriele.paoloni@intel.com>
+ *             Aidan O'Mahony (aidan.o.mahony@intel.com)
+ *    Copyright (c) 2010, Intel Corporation.
+ */
+
+#ifndef _CRYPTO_CRYPT_H
+#define _CRYPTO_CRYPT_H
+
+#include <linux/types.h>
+
+#include <crypto/aead.h>
+
+struct cryptd_aead {
+	struct crypto_aead base;
+};
+
+static inline struct cryptd_aead *__cryptd_aead_cast(
+	struct crypto_aead *tfm)
+{
+	return (struct cryptd_aead *)tfm;
+}
+
+struct cryptd_aead *cryptd_alloc_aead(const char *alg_name,
+					  u32 type, u32 mask);
+
+struct crypto_aead *cryptd_aead_child(struct cryptd_aead *tfm);
+/* Must be called without moving CPUs. */
+bool cryptd_aead_queued(struct cryptd_aead *tfm);
+
+void cryptd_free_aead(struct cryptd_aead *tfm);
+
+#endif