From 6668ed271eaefaa63e686bdfbedaeb7b8e492722 Mon Sep 17 00:00:00 2001 From: Kumar Kartikeya Dwivedi Date: Fri, 4 Sep 2026 10:43:19 +0200 Subject: selftests/bpf: Reject graph kptr use after RCU unlock 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 Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- include/crypto/public_key.h | 124 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 124 insertions(+) create mode 100644 include/crypto/public_key.h (limited to 'include/crypto/public_key.h') diff --git a/include/crypto/public_key.h b/include/crypto/public_key.h new file mode 100644 index 000000000..4c5199b20 --- /dev/null +++ b/include/crypto/public_key.h @@ -0,0 +1,124 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* Asymmetric public-key algorithm definitions + * + * See Documentation/crypto/asymmetric-keys.rst + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#ifndef _LINUX_PUBLIC_KEY_H +#define _LINUX_PUBLIC_KEY_H + +#include +#include +#include + +/* + * Cryptographic data for the public-key subtype of the asymmetric key type. + * + * Note that this may include private part of the key as well as the public + * part. + */ +struct public_key { + void *key; + u32 keylen; + enum OID algo; + void *params; + u32 paramlen; + bool key_is_private; + const char *id_type; + const char *pkey_algo; + unsigned long key_eflags; /* key extension flags */ +#define KEY_EFLAG_CA 0 /* set if the CA basic constraints is set */ +#define KEY_EFLAG_DIGITALSIG 1 /* set if the digitalSignature usage is set */ +#define KEY_EFLAG_KEYCERTSIGN 2 /* set if the keyCertSign usage is set */ +}; + +extern void public_key_free(struct public_key *key); + +/* + * Public key cryptography signature data + */ +struct public_key_signature { + struct asymmetric_key_id *auth_ids[3]; + u8 *s; /* Signature */ + u8 *m; /* Message data to pass to verifier */ + u32 s_size; /* Number of bytes in signature */ + u32 m_size; /* Number of bytes in ->m */ + bool m_free; /* T if ->m needs freeing */ + bool algo_takes_data; /* T if public key algo operates on data, not a hash */ + const char *pkey_algo; + const char *hash_algo; + const char *encoding; +}; + +extern void public_key_signature_free(struct public_key_signature *sig); + +extern struct asymmetric_key_subtype public_key_subtype; + +struct key; +struct key_type; +union key_payload; + +extern int restrict_link_by_signature(struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *trust_keyring); + +extern int restrict_link_by_key_or_keyring(struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *trusted); + +extern int restrict_link_by_key_or_keyring_chain(struct key *trust_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *trusted); + +#if IS_REACHABLE(CONFIG_ASYMMETRIC_KEY_TYPE) +extern int restrict_link_by_ca(struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *trust_keyring); +int restrict_link_by_digsig(struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *trust_keyring); +#else +static inline int restrict_link_by_ca(struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *trust_keyring) +{ + return 0; +} + +static inline int restrict_link_by_digsig(struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *trust_keyring) +{ + return 0; +} +#endif + +extern int query_asymmetric_key(const struct kernel_pkey_params *, + struct kernel_pkey_query *); + +extern int verify_signature(const struct key *, + const struct public_key_signature *); + +#if IS_REACHABLE(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE) +int public_key_verify_signature(const struct public_key *pkey, + const struct public_key_signature *sig); +#else +static inline +int public_key_verify_signature(const struct public_key *pkey, + const struct public_key_signature *sig) +{ + return -EINVAL; +} +#endif + +#endif /* _LINUX_PUBLIC_KEY_H */ -- cgit v1.3.1