From 5febf432df1cfa5b25d99b54c32103fafbdd0eb9 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sun, 16 Aug 2026 15:32:33 +0200 Subject: kbuild: rust: keep Rust objects out of Clang LTO with inline helpers Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit `objtool` errors such as: vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a: can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd The reason is that in such builds, the Clang invocation that compiles the combined Rust plus helpers bitcode emits LLVM bitcode (again) -- the final code generation happens in the linker's LTO step, which the `-mllvm` trap options passed to Clang do not reach. This, in turn, means that unreachable traps are missing, and the impossible paths do not merely fallthrough to the next symbol, but past the end of their own section, since LTO builds place each function in its own section. Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always emits machine code directly, with the traps in place. Assisted-by: LLM Cc: Gary Guo Cc: Boqun Feng Cc: Alice Ryhl Cc: Matthew Maurer Cc: Josh Poimboeuf Cc: Peter Zijlstra Cc: stable@vger.kernel.org Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust") Acked-by: Gary Guo Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda --- security/integrity/digsig.c | 228 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 228 insertions(+) create mode 100644 security/integrity/digsig.c (limited to 'security/integrity/digsig.c') diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c new file mode 100644 index 000000000..1ed686154 --- /dev/null +++ b/security/integrity/digsig.c @@ -0,0 +1,228 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2011 Intel Corporation + * + * Author: + * Dmitry Kasatkin + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "integrity.h" + +static struct key *keyring[INTEGRITY_KEYRING_MAX]; + +static const char * const keyring_name[INTEGRITY_KEYRING_MAX] = { +#ifndef CONFIG_INTEGRITY_TRUSTED_KEYRING + "_evm", + "_ima", +#else + ".evm", + ".ima", +#endif + ".platform", + ".machine", +}; + +#ifdef CONFIG_IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARY +#define restrict_link_to_ima restrict_link_by_digsig_builtin_and_secondary +#else +#define restrict_link_to_ima restrict_link_by_digsig_builtin +#endif + +static struct key *integrity_keyring_from_id(const unsigned int id) +{ + if (id >= INTEGRITY_KEYRING_MAX) + return ERR_PTR(-EINVAL); + + if (!keyring[id]) { + keyring[id] = + request_key(&key_type_keyring, keyring_name[id], NULL); + if (IS_ERR(keyring[id])) { + int err = PTR_ERR(keyring[id]); + pr_err("no %s keyring: %d\n", keyring_name[id], err); + keyring[id] = NULL; + return ERR_PTR(err); + } + } + + return keyring[id]; +} + +int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen, + const char *digest, int digestlen, u8 algo) +{ + struct key *keyring; + + if (siglen < 2) + return -EINVAL; + + keyring = integrity_keyring_from_id(id); + if (IS_ERR(keyring)) + return PTR_ERR(keyring); + + switch (sig[1]) { + case 1: + /* v1 API expect signature without xattr type */ + return digsig_verify(keyring, sig + 1, siglen - 1, digest, + digestlen); + case 2: /* regular file data hash based signature */ + return asymmetric_verify(keyring, sig, siglen, digest, + digestlen); + case 3: /* struct ima_file_id data based signature */ + return asymmetric_verify_v3(keyring, sig, siglen, digest, + digestlen, algo); + } + + return -EOPNOTSUPP; +} + +int integrity_modsig_verify(const unsigned int id, const struct modsig *modsig) +{ + struct key *keyring; + + keyring = integrity_keyring_from_id(id); + if (IS_ERR(keyring)) + return PTR_ERR(keyring); + + return ima_modsig_verify(keyring, modsig); +} + +static int __init __integrity_init_keyring(const unsigned int id, + key_perm_t perm, + struct key_restriction *restriction) +{ + const struct cred *cred = current_cred(); + int err = 0; + + keyring[id] = keyring_alloc(keyring_name[id], KUIDT_INIT(0), + KGIDT_INIT(0), cred, perm, + KEY_ALLOC_NOT_IN_QUOTA, restriction, NULL); + if (IS_ERR(keyring[id])) { + err = PTR_ERR(keyring[id]); + pr_info("Can't allocate %s keyring (%d)\n", + keyring_name[id], err); + keyring[id] = NULL; + } else { + if (id == INTEGRITY_KEYRING_PLATFORM) + set_platform_trusted_keys(keyring[id]); + if (id == INTEGRITY_KEYRING_MACHINE && imputed_trust_enabled()) + set_machine_trusted_keys(keyring[id]); + if (id == INTEGRITY_KEYRING_IMA) + load_module_cert(keyring[id]); + } + + return err; +} + +int __init integrity_init_keyring(const unsigned int id) +{ + struct key_restriction *restriction; + key_perm_t perm; + int ret; + + perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_VIEW + | KEY_USR_READ | KEY_USR_SEARCH; + + if (id == INTEGRITY_KEYRING_PLATFORM || + (id == INTEGRITY_KEYRING_MACHINE && + !IS_ENABLED(CONFIG_INTEGRITY_CA_MACHINE_KEYRING))) { + restriction = NULL; + goto out; + } + + if (!IS_ENABLED(CONFIG_INTEGRITY_TRUSTED_KEYRING)) + return 0; + + restriction = kzalloc_obj(struct key_restriction); + if (!restriction) + return -ENOMEM; + + if (id == INTEGRITY_KEYRING_MACHINE) + restriction->check = restrict_link_by_ca; + else + restriction->check = restrict_link_to_ima; + + /* + * MOK keys can only be added through a read-only runtime services + * UEFI variable during boot. No additional keys shall be allowed to + * load into the machine keyring following init from userspace. + */ + if (id != INTEGRITY_KEYRING_MACHINE) + perm |= KEY_USR_WRITE; + +out: + ret = __integrity_init_keyring(id, perm, restriction); + if (ret) + kfree(restriction); + return ret; +} + +static int __init integrity_add_key(const unsigned int id, const void *data, + off_t size, key_perm_t perm) +{ + key_ref_t key; + int rc = 0; + + if (!keyring[id]) + return -EINVAL; + + key = key_create_or_update(make_key_ref(keyring[id], 1), "asymmetric", + NULL, data, size, perm, + KEY_ALLOC_NOT_IN_QUOTA); + if (IS_ERR(key)) { + rc = PTR_ERR(key); + if (id != INTEGRITY_KEYRING_MACHINE) + pr_err("Problem loading X.509 certificate %d\n", rc); + } else { + pr_notice("Loaded X.509 cert '%s'\n", + key_ref_to_ptr(key)->description); + key_ref_put(key); + } + + return rc; + +} + +int __init integrity_load_x509(const unsigned int id, const char *path) +{ + void *data = NULL; + size_t size; + int rc; + key_perm_t perm; + + rc = kernel_read_file_from_path(path, 0, &data, INT_MAX, NULL, + READING_X509_CERTIFICATE); + if (rc < 0) { + pr_err("Unable to open file: %s (%d)", path, rc); + return rc; + } + size = rc; + + perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_VIEW | KEY_USR_READ; + + pr_info("Loading X.509 certificate: %s\n", path); + rc = integrity_add_key(id, (const void *)data, size, perm); + + vfree(data); + return rc; +} + +int __init integrity_load_cert(const unsigned int id, const char *source, + const void *data, size_t len, key_perm_t perm) +{ + if (!data) + return -EINVAL; + + pr_info("Loading X.509 certificate: %s\n", source); + return integrity_add_key(id, data, len, perm); +} -- cgit v1.3.1