From 27600805e62f800bacf990354632eae4e487d34c Mon Sep 17 00:00:00 2001 From: Yazen Ghannam Date: Thu, 3 Sep 2026 10:43:25 -0500 Subject: x86/amd_node: Fix PCI device reference counting in amd_smn_init() The local "root" pointer is a temporary variable used during the device search. Therefore, refcount related to the search iterators should be cleaned up after the search is complete. Use the __free() cleanup macro to ensure the refcount is decremented when the temporary pointer goes out of scope. Additionally, increment the refcount when caching a root pointer. This ensures the in-use refcount is separate from the temporary search refcounting. Finally, drop the redundant "root = NULL" before the second search loop. The pci_get_class() iterator always decrements the refcount of its "from" argument, so the first loop can only fall through with "root" already NULL. Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching") Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com Reported-by: Sashiko Assisted-by: LLM Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Mario Limonciello (AMD) Cc: Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com --- crypto/ecdh.c | 247 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 247 insertions(+) create mode 100644 crypto/ecdh.c (limited to 'crypto/ecdh.c') diff --git a/crypto/ecdh.c b/crypto/ecdh.c new file mode 100644 index 000000000..9f0b93b31 --- /dev/null +++ b/crypto/ecdh.c @@ -0,0 +1,247 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* ECDH key-agreement protocol + * + * Copyright (c) 2016, Intel Corporation + * Authors: Salvator Benedetto + */ + +#include +#include +#include +#include +#include +#include + +struct ecdh_ctx { + unsigned int curve_id; + unsigned int ndigits; + u64 private_key[ECC_MAX_DIGITS]; +}; + +static inline struct ecdh_ctx *ecdh_get_ctx(struct crypto_kpp *tfm) +{ + return kpp_tfm_ctx(tfm); +} + +static int ecdh_set_secret(struct crypto_kpp *tfm, const void *buf, + unsigned int len) +{ + struct ecdh_ctx *ctx = ecdh_get_ctx(tfm); + struct ecdh params; + int ret = 0; + + if (crypto_ecdh_decode_key(buf, len, ¶ms) < 0 || + params.key_size > sizeof(u64) * ctx->ndigits) + return -EINVAL; + + memset(ctx->private_key, 0, sizeof(ctx->private_key)); + + if (!params.key || !params.key_size) + return ecc_gen_privkey(ctx->curve_id, ctx->ndigits, + ctx->private_key); + + ecc_digits_from_bytes(params.key, params.key_size, + ctx->private_key, ctx->ndigits); + + if (ecc_is_key_valid(ctx->curve_id, ctx->ndigits, + ctx->private_key, params.key_size) < 0) { + memzero_explicit(ctx->private_key, params.key_size); + ret = -EINVAL; + } + + return ret; +} + +static int ecdh_compute_value(struct kpp_request *req) +{ + struct crypto_kpp *tfm = crypto_kpp_reqtfm(req); + struct ecdh_ctx *ctx = ecdh_get_ctx(tfm); + u64 *public_key; + u64 *shared_secret = NULL; + void *buf; + size_t copied, nbytes, public_key_sz; + int ret = -ENOMEM; + + nbytes = ctx->ndigits << ECC_DIGITS_TO_BYTES_SHIFT; + /* Public part is a point thus it has both coordinates */ + public_key_sz = 2 * nbytes; + + public_key = kmalloc(public_key_sz, GFP_KERNEL); + if (!public_key) + return -ENOMEM; + + if (req->src) { + shared_secret = kmalloc(nbytes, GFP_KERNEL); + if (!shared_secret) + goto free_pubkey; + + /* from here on it's invalid parameters */ + ret = -EINVAL; + + /* must have exactly two points to be on the curve */ + if (public_key_sz != req->src_len) + goto free_all; + + copied = sg_copy_to_buffer(req->src, + sg_nents_for_len(req->src, + public_key_sz), + public_key, public_key_sz); + if (copied != public_key_sz) + goto free_all; + + ret = crypto_ecdh_shared_secret(ctx->curve_id, ctx->ndigits, + ctx->private_key, public_key, + shared_secret); + + buf = shared_secret; + } else { + ret = ecc_make_pub_key(ctx->curve_id, ctx->ndigits, + ctx->private_key, public_key); + buf = public_key; + nbytes = public_key_sz; + } + + if (ret < 0) + goto free_all; + + /* might want less than we've got */ + nbytes = min_t(size_t, nbytes, req->dst_len); + copied = sg_copy_from_buffer(req->dst, sg_nents_for_len(req->dst, + nbytes), + buf, nbytes); + if (copied != nbytes) + ret = -EINVAL; + + /* fall through */ +free_all: + kfree_sensitive(shared_secret); +free_pubkey: + kfree(public_key); + return ret; +} + +static unsigned int ecdh_max_size(struct crypto_kpp *tfm) +{ + struct ecdh_ctx *ctx = ecdh_get_ctx(tfm); + + /* Public key is made of two coordinates, add one to the left shift */ + return ctx->ndigits << (ECC_DIGITS_TO_BYTES_SHIFT + 1); +} + +static int ecdh_nist_p192_init_tfm(struct crypto_kpp *tfm) +{ + struct ecdh_ctx *ctx = ecdh_get_ctx(tfm); + + ctx->curve_id = ECC_CURVE_NIST_P192; + ctx->ndigits = ECC_CURVE_NIST_P192_DIGITS; + + return 0; +} + +static struct kpp_alg ecdh_nist_p192 = { + .set_secret = ecdh_set_secret, + .generate_public_key = ecdh_compute_value, + .compute_shared_secret = ecdh_compute_value, + .max_size = ecdh_max_size, + .init = ecdh_nist_p192_init_tfm, + .base = { + .cra_name = "ecdh-nist-p192", + .cra_driver_name = "ecdh-nist-p192-generic", + .cra_priority = 100, + .cra_module = THIS_MODULE, + .cra_ctxsize = sizeof(struct ecdh_ctx), + }, +}; + +static int ecdh_nist_p256_init_tfm(struct crypto_kpp *tfm) +{ + struct ecdh_ctx *ctx = ecdh_get_ctx(tfm); + + ctx->curve_id = ECC_CURVE_NIST_P256; + ctx->ndigits = ECC_CURVE_NIST_P256_DIGITS; + + return 0; +} + +static struct kpp_alg ecdh_nist_p256 = { + .set_secret = ecdh_set_secret, + .generate_public_key = ecdh_compute_value, + .compute_shared_secret = ecdh_compute_value, + .max_size = ecdh_max_size, + .init = ecdh_nist_p256_init_tfm, + .base = { + .cra_name = "ecdh-nist-p256", + .cra_driver_name = "ecdh-nist-p256-generic", + .cra_priority = 100, + .cra_module = THIS_MODULE, + .cra_ctxsize = sizeof(struct ecdh_ctx), + }, +}; + +static int ecdh_nist_p384_init_tfm(struct crypto_kpp *tfm) +{ + struct ecdh_ctx *ctx = ecdh_get_ctx(tfm); + + ctx->curve_id = ECC_CURVE_NIST_P384; + ctx->ndigits = ECC_CURVE_NIST_P384_DIGITS; + + return 0; +} + +static struct kpp_alg ecdh_nist_p384 = { + .set_secret = ecdh_set_secret, + .generate_public_key = ecdh_compute_value, + .compute_shared_secret = ecdh_compute_value, + .max_size = ecdh_max_size, + .init = ecdh_nist_p384_init_tfm, + .base = { + .cra_name = "ecdh-nist-p384", + .cra_driver_name = "ecdh-nist-p384-generic", + .cra_priority = 100, + .cra_module = THIS_MODULE, + .cra_ctxsize = sizeof(struct ecdh_ctx), + }, +}; + +static bool ecdh_nist_p192_registered; + +static int __init ecdh_init(void) +{ + int ret; + + /* NIST p192 will fail to register in FIPS mode */ + ret = crypto_register_kpp(&ecdh_nist_p192); + ecdh_nist_p192_registered = ret == 0; + + ret = crypto_register_kpp(&ecdh_nist_p256); + if (ret) + goto nist_p256_error; + + ret = crypto_register_kpp(&ecdh_nist_p384); + if (ret) + goto nist_p384_error; + + return 0; + +nist_p384_error: + crypto_unregister_kpp(&ecdh_nist_p256); + +nist_p256_error: + if (ecdh_nist_p192_registered) + crypto_unregister_kpp(&ecdh_nist_p192); + return ret; +} + +static void __exit ecdh_exit(void) +{ + if (ecdh_nist_p192_registered) + crypto_unregister_kpp(&ecdh_nist_p192); + crypto_unregister_kpp(&ecdh_nist_p256); + crypto_unregister_kpp(&ecdh_nist_p384); +} + +module_init(ecdh_init); +module_exit(ecdh_exit); +MODULE_ALIAS_CRYPTO("ecdh"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("ECDH generic algorithm"); -- cgit v1.3.1