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 --- crypto/algboss.c | 254 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 254 insertions(+) create mode 100644 crypto/algboss.c (limited to 'crypto/algboss.c') diff --git a/crypto/algboss.c b/crypto/algboss.c new file mode 100644 index 000000000..8b936cae6 --- /dev/null +++ b/crypto/algboss.c @@ -0,0 +1,254 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Create default crypto algorithm instances. + * + * Copyright (c) 2006 Herbert Xu + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "internal.h" + +struct cryptomgr_param { + struct rtattr *tb[CRYPTO_MAX_ATTRS + 2]; + + struct { + struct rtattr attr; + struct crypto_attr_type data; + } type; + + struct { + struct rtattr attr; + struct crypto_attr_alg data; + } attrs[CRYPTO_MAX_ATTRS]; + + char template[CRYPTO_MAX_ALG_NAME]; + + struct crypto_larval *larval; + + u32 otype; + u32 omask; +}; + +struct crypto_test_param { + char driver[CRYPTO_MAX_ALG_NAME]; + char alg[CRYPTO_MAX_ALG_NAME]; + u32 type; +}; + +static int cryptomgr_probe(void *data) +{ + struct cryptomgr_param *param = data; + struct crypto_template *tmpl; + int err = -ENOENT; + + tmpl = crypto_lookup_template(param->template); + if (!tmpl) + goto out; + + do { + err = tmpl->create(tmpl, param->tb); + } while (err == -EAGAIN && !signal_pending(current)); + + crypto_tmpl_put(tmpl); + +out: + param->larval->adult = ERR_PTR(err); + param->larval->alg.cra_flags |= CRYPTO_ALG_DEAD; + complete_all(¶m->larval->completion); + crypto_alg_put(¶m->larval->alg); + kfree(param); + module_put_and_kthread_exit(0); +} + +static int cryptomgr_schedule_probe(struct crypto_larval *larval) +{ + struct task_struct *thread; + struct cryptomgr_param *param; + const char *name = larval->alg.cra_name; + const char *p; + unsigned int len; + int i; + + if (!try_module_get(THIS_MODULE)) + goto err; + + param = kzalloc_obj(*param); + if (!param) + goto err_put_module; + + for (p = name; isalnum(*p) || *p == '-' || *p == '_'; p++) + ; + + len = p - name; + if (!len || *p != '(') + goto err_free_param; + + memcpy(param->template, name, len); + + i = 0; + for (;;) { + name = ++p; + + for (; isalnum(*p) || *p == '-' || *p == '_'; p++) + ; + + if (*p == '(') { + int recursion = 0; + + for (;;) { + if (!*++p) + goto err_free_param; + if (*p == '(') + recursion++; + else if (*p == ')' && !recursion--) + break; + } + + p++; + } + + len = p - name; + if (!len) + goto err_free_param; + + param->attrs[i].attr.rta_len = sizeof(param->attrs[i]); + param->attrs[i].attr.rta_type = CRYPTOA_ALG; + memcpy(param->attrs[i].data.name, name, len); + + param->tb[i + 1] = ¶m->attrs[i].attr; + i++; + + if (i >= CRYPTO_MAX_ATTRS) + goto err_free_param; + + if (*p == ')') + break; + + if (*p != ',') + goto err_free_param; + } + + param->tb[i + 1] = NULL; + + param->type.attr.rta_len = sizeof(param->type); + param->type.attr.rta_type = CRYPTOA_TYPE; + param->type.data.type = larval->alg.cra_flags & ~CRYPTO_ALG_TESTED; + param->type.data.mask = larval->mask & ~CRYPTO_ALG_TESTED; + param->tb[0] = ¶m->type.attr; + + param->otype = larval->alg.cra_flags; + param->omask = larval->mask; + + crypto_alg_get(&larval->alg); + param->larval = larval; + + thread = kthread_run(cryptomgr_probe, param, "cryptomgr_probe"); + if (IS_ERR(thread)) + goto err_put_larval; + + return NOTIFY_STOP; + +err_put_larval: + crypto_alg_put(&larval->alg); +err_free_param: + kfree(param); +err_put_module: + module_put(THIS_MODULE); +err: + return NOTIFY_OK; +} + +static int cryptomgr_test(void *data) +{ + struct crypto_test_param *param = data; + u32 type = param->type; + int err; + + err = alg_test(param->driver, param->alg, type, CRYPTO_ALG_TESTED); + + crypto_alg_tested(param->driver, err); + + kfree(param); + module_put_and_kthread_exit(0); +} + +static int cryptomgr_schedule_test(struct crypto_alg *alg) +{ + struct task_struct *thread; + struct crypto_test_param *param; + + if (!IS_ENABLED(CONFIG_CRYPTO_SELFTESTS)) + return NOTIFY_DONE; + + if (!try_module_get(THIS_MODULE)) + goto err; + + param = kzalloc_obj(*param); + if (!param) + goto err_put_module; + + memcpy(param->driver, alg->cra_driver_name, sizeof(param->driver)); + memcpy(param->alg, alg->cra_name, sizeof(param->alg)); + param->type = alg->cra_flags; + + thread = kthread_run(cryptomgr_test, param, "cryptomgr_test"); + if (IS_ERR(thread)) + goto err_free_param; + + return NOTIFY_STOP; + +err_free_param: + kfree(param); +err_put_module: + module_put(THIS_MODULE); +err: + return NOTIFY_OK; +} + +static int cryptomgr_notify(struct notifier_block *this, unsigned long msg, + void *data) +{ + switch (msg) { + case CRYPTO_MSG_ALG_REQUEST: + return cryptomgr_schedule_probe(data); + case CRYPTO_MSG_ALG_REGISTER: + return cryptomgr_schedule_test(data); + case CRYPTO_MSG_ALG_LOADED: + break; + } + + return NOTIFY_DONE; +} + +static struct notifier_block cryptomgr_notifier = { + .notifier_call = cryptomgr_notify, +}; + +static int __init cryptomgr_init(void) +{ + return crypto_register_notifier(&cryptomgr_notifier); +} + +static void __exit cryptomgr_exit(void) +{ + int err = crypto_unregister_notifier(&cryptomgr_notifier); + BUG_ON(err); +} + +module_init(cryptomgr_init); +module_exit(cryptomgr_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Crypto Algorithm Manager"); -- cgit v1.3.1