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/keys/system_keyring.h | 133 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 133 insertions(+) create mode 100644 include/keys/system_keyring.h (limited to 'include/keys/system_keyring.h') diff --git a/include/keys/system_keyring.h b/include/keys/system_keyring.h new file mode 100644 index 000000000..a6c2897bc --- /dev/null +++ b/include/keys/system_keyring.h @@ -0,0 +1,133 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* System keyring containing trusted public keys. + * + * Copyright (C) 2013 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#ifndef _KEYS_SYSTEM_KEYRING_H +#define _KEYS_SYSTEM_KEYRING_H + +#include + +enum blacklist_hash_type { + /* TBSCertificate hash */ + BLACKLIST_HASH_X509_TBS = 1, + /* Raw data hash */ + BLACKLIST_HASH_BINARY = 2, +}; + +#ifdef CONFIG_SYSTEM_TRUSTED_KEYRING + +extern int restrict_link_by_builtin_trusted(struct key *keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *restriction_key); +int restrict_link_by_digsig_builtin(struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *restriction_key); +extern __init int load_module_cert(struct key *keyring); + +#else +#define restrict_link_by_builtin_trusted restrict_link_reject +#define restrict_link_by_digsig_builtin restrict_link_reject + +static inline __init int load_module_cert(struct key *keyring) +{ + return 0; +} + +#endif + +#ifdef CONFIG_SECONDARY_TRUSTED_KEYRING +extern int restrict_link_by_builtin_and_secondary_trusted( + struct key *keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *restriction_key); +int restrict_link_by_digsig_builtin_and_secondary(struct key *keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *restriction_key); +void __init add_to_secondary_keyring(const char *source, const void *data, size_t len); +#else +#define restrict_link_by_builtin_and_secondary_trusted restrict_link_by_builtin_trusted +#define restrict_link_by_digsig_builtin_and_secondary restrict_link_by_digsig_builtin +static inline void __init add_to_secondary_keyring(const char *source, const void *data, size_t len) +{ +} +#endif + +#ifdef CONFIG_INTEGRITY_MACHINE_KEYRING +extern int restrict_link_by_builtin_secondary_and_machine( + struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *restrict_key); +extern void __init set_machine_trusted_keys(struct key *keyring); +#else +#define restrict_link_by_builtin_secondary_and_machine restrict_link_by_builtin_trusted +static inline void __init set_machine_trusted_keys(struct key *keyring) +{ +} +#endif + +#ifdef CONFIG_SYSTEM_BLACKLIST_KEYRING +extern int mark_hash_blacklisted(const u8 *hash, size_t hash_len, + enum blacklist_hash_type hash_type); +extern int is_hash_blacklisted(const u8 *hash, size_t hash_len, + enum blacklist_hash_type hash_type); +extern int is_binary_blacklisted(const u8 *hash, size_t hash_len); +#else +static inline int is_hash_blacklisted(const u8 *hash, size_t hash_len, + enum blacklist_hash_type hash_type) +{ + return 0; +} + +static inline int is_binary_blacklisted(const u8 *hash, size_t hash_len) +{ + return 0; +} +#endif + +struct pkcs7_message; +#ifdef CONFIG_SYSTEM_REVOCATION_LIST +extern int add_key_to_revocation_list(const char *data, size_t size); +extern int is_key_on_revocation_list(struct pkcs7_message *pkcs7); +#else +static inline int add_key_to_revocation_list(const char *data, size_t size) +{ + return 0; +} +static inline int is_key_on_revocation_list(struct pkcs7_message *pkcs7) +{ + return -ENOKEY; +} +#endif + +#ifdef CONFIG_IMA_BLACKLIST_KEYRING +extern struct key *ima_blacklist_keyring; + +static inline struct key *get_ima_blacklist_keyring(void) +{ + return ima_blacklist_keyring; +} +#else +static inline struct key *get_ima_blacklist_keyring(void) +{ + return NULL; +} +#endif /* CONFIG_IMA_BLACKLIST_KEYRING */ + +#if defined(CONFIG_INTEGRITY_PLATFORM_KEYRING) && \ + defined(CONFIG_SYSTEM_TRUSTED_KEYRING) +extern void __init set_platform_trusted_keys(struct key *keyring); +#else +static inline void set_platform_trusted_keys(struct key *keyring) +{ +} +#endif + +#endif /* _KEYS_SYSTEM_KEYRING_H */ -- cgit v1.3.1