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 --- lib/crypto/nh.c | 82 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 82 insertions(+) create mode 100644 lib/crypto/nh.c (limited to 'lib/crypto/nh.c') diff --git a/lib/crypto/nh.c b/lib/crypto/nh.c new file mode 100644 index 000000000..e1d0095b5 --- /dev/null +++ b/lib/crypto/nh.c @@ -0,0 +1,82 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2018 Google LLC + */ + +/* + * Implementation of the NH almost-universal hash function, specifically the + * variant of NH used in Adiantum. This is *not* a cryptographic hash function. + * + * Reference: section 6.3 of "Adiantum: length-preserving encryption for + * entry-level processors" (https://eprint.iacr.org/2018/720.pdf). + */ + +#include +#include +#include +#include +#include + +#ifdef CONFIG_CRYPTO_LIB_NH_ARCH +#include "nh.h" /* $(SRCARCH)/nh.h */ +#else +static bool nh_arch(const u32 *key, const u8 *message, size_t message_len, + __le64 hash[NH_NUM_PASSES]) +{ + return false; +} +#endif + +void nh(const u32 *key, const u8 *message, size_t message_len, + __le64 hash[NH_NUM_PASSES]) +{ + u64 sums[4] = { 0, 0, 0, 0 }; + + if (nh_arch(key, message, message_len, hash)) + return; + + static_assert(NH_PAIR_STRIDE == 2); + static_assert(NH_NUM_PASSES == 4); + + while (message_len) { + u32 m0 = get_unaligned_le32(message + 0); + u32 m1 = get_unaligned_le32(message + 4); + u32 m2 = get_unaligned_le32(message + 8); + u32 m3 = get_unaligned_le32(message + 12); + + sums[0] += (u64)(u32)(m0 + key[0]) * (u32)(m2 + key[2]); + sums[1] += (u64)(u32)(m0 + key[4]) * (u32)(m2 + key[6]); + sums[2] += (u64)(u32)(m0 + key[8]) * (u32)(m2 + key[10]); + sums[3] += (u64)(u32)(m0 + key[12]) * (u32)(m2 + key[14]); + sums[0] += (u64)(u32)(m1 + key[1]) * (u32)(m3 + key[3]); + sums[1] += (u64)(u32)(m1 + key[5]) * (u32)(m3 + key[7]); + sums[2] += (u64)(u32)(m1 + key[9]) * (u32)(m3 + key[11]); + sums[3] += (u64)(u32)(m1 + key[13]) * (u32)(m3 + key[15]); + key += NH_MESSAGE_UNIT / sizeof(key[0]); + message += NH_MESSAGE_UNIT; + message_len -= NH_MESSAGE_UNIT; + } + + hash[0] = cpu_to_le64(sums[0]); + hash[1] = cpu_to_le64(sums[1]); + hash[2] = cpu_to_le64(sums[2]); + hash[3] = cpu_to_le64(sums[3]); +} +EXPORT_SYMBOL_GPL(nh); + +#ifdef nh_mod_init_arch +static int __init nh_mod_init(void) +{ + nh_mod_init_arch(); + return 0; +} +subsys_initcall(nh_mod_init); + +static void __exit nh_mod_exit(void) +{ +} +module_exit(nh_mod_exit); +#endif + +MODULE_DESCRIPTION("NH almost-universal hash function"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1