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/sm4_generic.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 92 insertions(+) create mode 100644 crypto/sm4_generic.c (limited to 'crypto/sm4_generic.c') diff --git a/crypto/sm4_generic.c b/crypto/sm4_generic.c new file mode 100644 index 000000000..d57444e84 --- /dev/null +++ b/crypto/sm4_generic.c @@ -0,0 +1,92 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * SM4 Cipher Algorithm. + * + * Copyright (C) 2018 ARM Limited or its affiliates. + * All rights reserved. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +/** + * sm4_setkey - Set the SM4 key. + * @tfm: The %crypto_tfm that is used in the context. + * @in_key: The input key. + * @key_len: The size of the key. + * + * This function uses sm4_expandkey() to expand the key. + * &sm4_ctx _must_ be the private data embedded in @tfm which is + * retrieved with crypto_tfm_ctx(). + * + * Return: 0 on success; -EINVAL on failure (only happens for bad key lengths) + */ +static int sm4_setkey(struct crypto_tfm *tfm, const u8 *in_key, + unsigned int key_len) +{ + struct sm4_ctx *ctx = crypto_tfm_ctx(tfm); + + return sm4_expandkey(ctx, in_key, key_len); +} + +/* encrypt a block of text */ + +static void sm4_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) +{ + const struct sm4_ctx *ctx = crypto_tfm_ctx(tfm); + + sm4_crypt_block(ctx->rkey_enc, out, in); +} + +/* decrypt a block of text */ + +static void sm4_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) +{ + const struct sm4_ctx *ctx = crypto_tfm_ctx(tfm); + + sm4_crypt_block(ctx->rkey_dec, out, in); +} + +static struct crypto_alg sm4_alg = { + .cra_name = "sm4", + .cra_driver_name = "sm4-generic", + .cra_priority = 100, + .cra_flags = CRYPTO_ALG_TYPE_CIPHER, + .cra_blocksize = SM4_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct sm4_ctx), + .cra_module = THIS_MODULE, + .cra_u = { + .cipher = { + .cia_min_keysize = SM4_KEY_SIZE, + .cia_max_keysize = SM4_KEY_SIZE, + .cia_setkey = sm4_setkey, + .cia_encrypt = sm4_encrypt, + .cia_decrypt = sm4_decrypt + } + } +}; + +static int __init sm4_init(void) +{ + return crypto_register_alg(&sm4_alg); +} + +static void __exit sm4_fini(void) +{ + crypto_unregister_alg(&sm4_alg); +} + +module_init(sm4_init); +module_exit(sm4_fini); + +MODULE_DESCRIPTION("SM4 Cipher Algorithm"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS_CRYPTO("sm4"); +MODULE_ALIAS_CRYPTO("sm4-generic"); -- cgit v1.3.1