From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- 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