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 --- lib/crypto/tests/hash-test-template.h | 511 ++++++++++++++++++++++++++++++++++ 1 file changed, 511 insertions(+) create mode 100644 lib/crypto/tests/hash-test-template.h (limited to 'lib/crypto/tests/hash-test-template.h') diff --git a/lib/crypto/tests/hash-test-template.h b/lib/crypto/tests/hash-test-template.h new file mode 100644 index 000000000..bb6eaa509 --- /dev/null +++ b/lib/crypto/tests/hash-test-template.h @@ -0,0 +1,511 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Test cases for hash functions, including a benchmark. This is included by + * KUnit test suites that want to use it. See sha512_kunit.c for an example. + * + * Copyright 2025 Google LLC + */ +#include +#include +#include "test-utils.h" + +/* + * Test the hash function against a list of test vectors. + * + * Note that it's only necessary to run each test vector in one way (e.g., + * one-shot instead of incremental), since consistency between different ways of + * using the APIs is verified by other test cases. + */ +static void test_hash_test_vectors(struct kunit *test) +{ + const size_t max_len = 16384; + u8 *data = alloc_buf(test, max_len); + + for (size_t i = 0; i < ARRAY_SIZE(hash_testvecs); i++) { + size_t data_len = hash_testvecs[i].data_len; + u8 actual_hash[HASH_SIZE]; + + KUNIT_ASSERT_LE(test, data_len, max_len); + rand_bytes_seeded_from_len(data, data_len); + HASH(data, data_len, actual_hash); + KUNIT_ASSERT_MEMEQ_MSG( + test, actual_hash, hash_testvecs[i].digest, HASH_SIZE, + "Wrong result with test vector %zu; data_len=%zu", i, + data_len); + } +} + +/* + * Test that the hash function produces correct results for *every* length up to + * 4096 bytes. To do this, generate seeded random data, then calculate a hash + * value for each length 0..4096, then hash the hash values. Verify just the + * final hash value, which should match only when all hash values were correct. + */ +static void test_hash_all_lens_up_to_4096(struct kunit *test) +{ + const size_t max_len = 4096; + u8 *data = alloc_buf(test, max_len); + struct HASH_CTX ctx; + u8 hash[HASH_SIZE]; + + rand_bytes_seeded_from_len(data, max_len); + HASH_INIT(&ctx); + for (size_t len = 0; len <= max_len; len++) { + HASH(data, len, hash); + HASH_UPDATE(&ctx, hash, HASH_SIZE); + } + HASH_FINAL(&ctx, hash); + KUNIT_ASSERT_MEMEQ(test, hash, hash_testvec_consolidated, HASH_SIZE); +} + +/* + * Test that the hash function produces the same result with a one-shot + * computation as it does with an incremental computation. + */ +static void test_hash_incremental_updates(struct kunit *test) +{ + const size_t max_len = 16384; + u8 *data = alloc_guarded_buf(test, max_len); + + for (int i = 0; i < 1000; i++) { + size_t total_len, offset; + struct HASH_CTX ctx; + u8 hash1[HASH_SIZE]; + u8 hash2[HASH_SIZE]; + size_t num_parts = 0; + size_t remaining_len, cur_offset; + + total_len = rand_length(max_len); + offset = rand_offset(max_len - total_len); + rand_bytes(&data[offset], total_len); + + /* Compute the hash value in one shot. */ + HASH(&data[offset], total_len, hash1); + + /* + * Compute the hash value incrementally, using a randomly + * selected sequence of update lengths that sum to total_len. + */ + HASH_INIT(&ctx); + remaining_len = total_len; + cur_offset = offset; + while (rand_bool()) { + size_t part_len = rand_length(remaining_len); + + HASH_UPDATE(&ctx, &data[cur_offset], part_len); + num_parts++; + cur_offset += part_len; + remaining_len -= part_len; + } + if (remaining_len != 0 || rand_bool()) { + HASH_UPDATE(&ctx, &data[cur_offset], remaining_len); + num_parts++; + } + HASH_FINAL(&ctx, hash2); + + /* Verify that the two hash values are the same. */ + KUNIT_ASSERT_MEMEQ_MSG( + test, hash1, hash2, HASH_SIZE, + "Incremental test failed with total_len=%zu num_parts=%zu offset=%zu", + total_len, num_parts, offset); + } +} + +/* + * Test that the hash function does not overrun any buffers. Uses a guard page + * to catch buffer overruns even if they occur in assembly code. + */ +static void test_hash_buffer_overruns(struct kunit *test) +{ + const size_t buf_len = 16384; + u8 *buf = alloc_guarded_buf(test, buf_len); + void *const buf_end = &buf[buf_len]; + const size_t max_tested_len = buf_len - sizeof(struct HASH_CTX); + struct HASH_CTX *guarded_ctx = buf_end - sizeof(*guarded_ctx); + + rand_bytes(buf, buf_len); + + for (int i = 0; i < 100; i++) { + size_t len = rand_length(max_tested_len); + struct HASH_CTX ctx; + u8 hash[HASH_SIZE]; + + /* Check for overruns of the data buffer. */ + HASH(buf_end - len, len, hash); + HASH_INIT(&ctx); + HASH_UPDATE(&ctx, buf_end - len, len); + HASH_FINAL(&ctx, hash); + + /* Check for overruns of the hash value buffer. */ + HASH(buf, len, buf_end - HASH_SIZE); + HASH_INIT(&ctx); + HASH_UPDATE(&ctx, buf, len); + HASH_FINAL(&ctx, buf_end - HASH_SIZE); + + /* Check for overruns of the hash context. */ + HASH_INIT(guarded_ctx); + HASH_UPDATE(guarded_ctx, buf, len); + HASH_FINAL(guarded_ctx, hash); + } +} + +/* + * Test that the caller is permitted to alias the output digest and source data + * buffer, and also modify the source data buffer after it has been used. + */ +static void test_hash_overlaps(struct kunit *test) +{ + const size_t buf_len = 16384; + u8 *buf = alloc_guarded_buf(test, buf_len); + const size_t max_tested_len = buf_len - HASH_SIZE; + struct HASH_CTX ctx; + u8 hash[HASH_SIZE]; + + rand_bytes(buf, buf_len); + + for (int i = 0; i < 100; i++) { + size_t len = rand_length(max_tested_len); + size_t offset = HASH_SIZE + rand_offset(max_tested_len - len); + bool left_end = rand_bool(); + u8 *ovl_hash = left_end ? &buf[offset] : + &buf[offset + len - HASH_SIZE]; + + HASH(&buf[offset], len, hash); + HASH(&buf[offset], len, ovl_hash); + KUNIT_ASSERT_MEMEQ_MSG( + test, hash, ovl_hash, HASH_SIZE, + "Overlap test 1 failed with len=%zu offset=%zu left_end=%d", + len, offset, left_end); + + /* Repeat the above test, but this time use init+update+final */ + HASH(&buf[offset], len, hash); + HASH_INIT(&ctx); + HASH_UPDATE(&ctx, &buf[offset], len); + HASH_FINAL(&ctx, ovl_hash); + KUNIT_ASSERT_MEMEQ_MSG( + test, hash, ovl_hash, HASH_SIZE, + "Overlap test 2 failed with len=%zu offset=%zu left_end=%d", + len, offset, left_end); + + /* Test modifying the source data after it was used. */ + HASH(&buf[offset], len, hash); + HASH_INIT(&ctx); + HASH_UPDATE(&ctx, &buf[offset], len); + rand_bytes(&buf[offset], len); + HASH_FINAL(&ctx, ovl_hash); + KUNIT_ASSERT_MEMEQ_MSG( + test, hash, ovl_hash, HASH_SIZE, + "Overlap test 3 failed with len=%zu offset=%zu left_end=%d", + len, offset, left_end); + } +} + +/* + * Test that if the same data is hashed at different alignments in memory, the + * results are the same. + */ +static void test_hash_alignment_consistency(struct kunit *test) +{ + const size_t max_len = 16384; + u8 *data = alloc_guarded_buf(test, max_len); + u8 hash1[128 + HASH_SIZE]; + u8 hash2[128 + HASH_SIZE]; + + for (int i = 0; i < 100; i++) { + size_t len = rand_length(max_len); + size_t data_offs1 = rand_offset(max_len - len); + size_t data_offs2 = rand_offset(max_len - len); + size_t hash_offs1 = rand_offset(128); + size_t hash_offs2 = rand_offset(128); + + rand_bytes(&data[data_offs1], len); + HASH(&data[data_offs1], len, &hash1[hash_offs1]); + memmove(&data[data_offs2], &data[data_offs1], len); + HASH(&data[data_offs2], len, &hash2[hash_offs2]); + KUNIT_ASSERT_MEMEQ_MSG( + test, &hash1[hash_offs1], &hash2[hash_offs2], HASH_SIZE, + "Alignment consistency test failed with len=%zu data_offs=(%zu,%zu) hash_offs=(%zu,%zu)", + len, data_offs1, data_offs2, hash_offs1, hash_offs2); + } +} + +/* Test that HASH_FINAL zeroizes the context. */ +static void test_hash_ctx_zeroization(struct kunit *test) +{ + static const u8 zeroes[sizeof(struct HASH_CTX)]; + struct HASH_CTX ctx; + const size_t data_len = 128; + u8 *data = alloc_buf(test, data_len); + u8 hash[HASH_SIZE]; + + rand_bytes(data, data_len); + HASH_INIT(&ctx); + HASH_UPDATE(&ctx, data, data_len); + HASH_FINAL(&ctx, hash); + KUNIT_ASSERT_MEMEQ_MSG(test, &ctx, zeroes, sizeof(ctx), + "Hash context was not zeroized by finalization"); +} + +#define IRQ_TEST_DATA_LEN 256 +#define IRQ_TEST_NUM_BUFFERS 3 /* matches max concurrency level */ + +struct hash_irq_test1_state { + u8 *data; + u8 expected_hashes[IRQ_TEST_NUM_BUFFERS][HASH_SIZE]; + atomic_t seqno; +}; + +/* + * Compute the hash of one of the test messages and verify that it matches the + * expected hash from @state->expected_hashes. To increase the chance of + * detecting problems, cycle through multiple messages. + */ +static bool hash_irq_test1_func(void *state_) +{ + struct hash_irq_test1_state *state = state_; + u32 i = (u32)atomic_inc_return(&state->seqno) % IRQ_TEST_NUM_BUFFERS; + u8 actual_hash[HASH_SIZE]; + + HASH(&state->data[i * IRQ_TEST_DATA_LEN], IRQ_TEST_DATA_LEN, + actual_hash); + return memcmp(actual_hash, state->expected_hashes[i], HASH_SIZE) == 0; +} + +/* + * Test that if hashes are computed in task, softirq, and hardirq context + * concurrently, then all results are as expected. + */ +static void test_hash_interrupt_context_1(struct kunit *test) +{ + const size_t total_data_len = IRQ_TEST_NUM_BUFFERS * IRQ_TEST_DATA_LEN; + struct hash_irq_test1_state state = {}; + + /* Prepare some test messages and compute the expected hash of each. */ + state.data = alloc_buf(test, total_data_len); + rand_bytes(state.data, total_data_len); + for (int i = 0; i < IRQ_TEST_NUM_BUFFERS; i++) + HASH(&state.data[i * IRQ_TEST_DATA_LEN], IRQ_TEST_DATA_LEN, + state.expected_hashes[i]); + + kunit_run_irq_test(test, hash_irq_test1_func, 100000, &state); +} + +struct hash_irq_test2_hash_ctx { + struct HASH_CTX hash_ctx; + atomic_t in_use; + int offset; + int step; +}; + +struct hash_irq_test2_state { + u8 *data; + size_t data_len; + struct hash_irq_test2_hash_ctx ctxs[IRQ_TEST_NUM_BUFFERS]; + u8 expected_hash[HASH_SIZE]; + u16 update_lens[32]; + int num_steps; +}; + +static bool hash_irq_test2_func(void *state_) +{ + struct hash_irq_test2_state *state = state_; + struct hash_irq_test2_hash_ctx *ctx; + bool ret = true; + + for (ctx = &state->ctxs[0]; ctx < &state->ctxs[ARRAY_SIZE(state->ctxs)]; + ctx++) { + if (atomic_cmpxchg(&ctx->in_use, 0, 1) == 0) + break; + } + if (WARN_ON_ONCE(ctx == &state->ctxs[ARRAY_SIZE(state->ctxs)])) { + /* + * This should never happen, as the number of contexts is equal + * to the maximum concurrency level of kunit_run_irq_test(). + */ + return false; + } + + if (ctx->step == 0) { + /* Init step */ + HASH_INIT(&ctx->hash_ctx); + ctx->offset = 0; + ctx->step++; + } else if (ctx->step < state->num_steps - 1) { + /* Update step */ + HASH_UPDATE(&ctx->hash_ctx, &state->data[ctx->offset], + state->update_lens[ctx->step - 1]); + ctx->offset += state->update_lens[ctx->step - 1]; + ctx->step++; + } else { + /* Final step */ + u8 actual_hash[HASH_SIZE]; + + if (WARN_ON_ONCE(ctx->offset != state->data_len)) + ret = false; + HASH_FINAL(&ctx->hash_ctx, actual_hash); + if (memcmp(actual_hash, state->expected_hash, HASH_SIZE) != 0) + ret = false; + ctx->step = 0; + } + atomic_set_release(&ctx->in_use, 0); + return ret; +} + +/* + * Test that if hashes are computed in task, softirq, and hardirq context + * concurrently, *including doing different parts of the same incremental + * computation in different contexts*, then all results are as expected. + * Besides detecting bugs similar to those that test_hash_interrupt_context_1 + * can detect, this test case can also detect bugs where hash function + * implementations don't correctly handle these mixed incremental computations. + */ +static void test_hash_interrupt_context_2(struct kunit *test) +{ + const size_t data_len = 16384; + struct hash_irq_test2_state *state; + size_t remaining = data_len; + + state = kunit_kzalloc(test, sizeof(*state), GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, state); + state->data_len = data_len; + state->data = alloc_buf(test, data_len); + + rand_bytes(state->data, data_len); + HASH(state->data, data_len, state->expected_hash); + + /* + * Generate a list of update lengths to use. Ensure that it contains + * multiple entries but is limited to a maximum length. + */ + KUNIT_ASSERT_GT(test, data_len / 4096, 1); + for (state->num_steps = 0; + state->num_steps < ARRAY_SIZE(state->update_lens) - 1 && remaining; + state->num_steps++) { + state->update_lens[state->num_steps] = + rand_length(min(remaining, 4096)); + remaining -= state->update_lens[state->num_steps]; + } + if (remaining) + state->update_lens[state->num_steps++] = remaining; + state->num_steps += 2; /* for init and final */ + + kunit_run_irq_test(test, hash_irq_test2_func, 250000, state); +} + +#define UNKEYED_HASH_KUNIT_CASES \ + KUNIT_CASE(test_hash_test_vectors), \ + KUNIT_CASE(test_hash_all_lens_up_to_4096), \ + KUNIT_CASE(test_hash_incremental_updates), \ + KUNIT_CASE(test_hash_buffer_overruns), \ + KUNIT_CASE(test_hash_overlaps), \ + KUNIT_CASE(test_hash_alignment_consistency), \ + KUNIT_CASE(test_hash_ctx_zeroization), \ + KUNIT_CASE(test_hash_interrupt_context_1), \ + KUNIT_CASE(test_hash_interrupt_context_2) +/* benchmark_hash is omitted so that the suites can put it last. */ + +#ifdef HMAC +/* + * Test the corresponding HMAC variant. + * + * This test case is fairly short, since HMAC is just a simple C wrapper around + * the underlying unkeyed hash function, which is already well-tested by the + * other test cases. It's not useful to test things like data alignment or + * interrupt context again for HMAC, nor to have a long list of test vectors. + * + * Thus, just do a single consolidated test, which covers all data lengths up to + * 4096 bytes and all key lengths up to 292 bytes. For each data length, select + * a key length, generate the inputs from a seed, and compute the HMAC value. + * Concatenate all these HMAC values together, and compute the HMAC of that. + * Verify that value. If this fails, then the HMAC implementation is wrong. + * This won't show which specific input failed, but that should be fine. Any + * failure would likely be non-input-specific or also show in the unkeyed tests. + */ +static void test_hmac(struct kunit *test) +{ + const size_t max_data_len = 4096; + const size_t max_key_len = 293; + const size_t outer_key_len = 32; + u8 *data = alloc_guarded_buf(test, max_data_len); + u8 *raw_key = alloc_guarded_buf(test, max_key_len); + static const u8 zeroes[sizeof(struct HMAC_CTX)]; + struct HMAC_KEY key; + struct HMAC_CTX ctx; + u8 mac[HASH_SIZE]; + u8 mac2[HASH_SIZE]; + + rand_bytes_seeded_from_len(data, max_data_len); + rand_bytes_seeded_from_len(raw_key, outer_key_len); + + HMAC_PREPAREKEY(&key, raw_key, outer_key_len); + HMAC_INIT(&ctx, &key); + for (size_t data_len = 0; data_len <= max_data_len; data_len++) { + /* + * Cycle through key lengths as well. Somewhat arbitrarily go + * up to 293, which is somewhat larger than the largest hash + * block size (which is the size at which the key starts being + * hashed down to one block); going higher would not be useful. + * To reduce correlation with data_len, use a prime number here. + */ + size_t key_len = data_len % max_key_len; + + HMAC_UPDATE(&ctx, data, data_len); + + rand_bytes_seeded_from_len(raw_key, key_len); + HMAC_USINGRAWKEY(raw_key, key_len, data, data_len, mac); + HMAC_UPDATE(&ctx, mac, HASH_SIZE); + + /* Verify that HMAC() is consistent with HMAC_USINGRAWKEY(). */ + HMAC_PREPAREKEY(&key, raw_key, key_len); + HMAC(&key, data, data_len, mac2); + KUNIT_ASSERT_MEMEQ_MSG( + test, mac, mac2, HASH_SIZE, + "HMAC gave different results with raw and prepared keys"); + } + HMAC_FINAL(&ctx, mac); + KUNIT_EXPECT_MEMEQ_MSG(test, mac, hmac_testvec_consolidated, HASH_SIZE, + "HMAC gave wrong result"); + KUNIT_EXPECT_MEMEQ_MSG(test, &ctx, zeroes, sizeof(ctx), + "HMAC context was not zeroized by finalization"); +} +#define HASH_KUNIT_CASES UNKEYED_HASH_KUNIT_CASES, KUNIT_CASE(test_hmac) +#else +#define HASH_KUNIT_CASES UNKEYED_HASH_KUNIT_CASES +#endif + +/* Benchmark the hash function on various data lengths. */ +static void benchmark_hash(struct kunit *test) +{ + static const size_t lens_to_test[] = { + 1, 16, 64, 127, 128, 200, 256, + 511, 512, 1024, 3173, 4096, 16384, + }; + const size_t max_len = 16384; + u8 *data = alloc_buf(test, max_len); + u8 hash[HASH_SIZE]; + + if (!IS_ENABLED(CONFIG_CRYPTO_LIB_BENCHMARK)) + kunit_skip(test, "not enabled"); + + /* Warm-up */ + memset(data, 0, max_len); + for (size_t i = 0; i < 10000000; i += max_len) + HASH(data, max_len, hash); + + for (size_t i = 0; i < ARRAY_SIZE(lens_to_test); i++) { + size_t len = lens_to_test[i]; + /* The '+ 128' tries to account for per-message overhead. */ + size_t num_iters = 10000000 / (len + 128); + u64 t; + + KUNIT_ASSERT_LE(test, len, max_len); + preempt_disable(); + t = ktime_get_ns(); + for (size_t j = 0; j < num_iters; j++) + HASH(data, len, hash); + t = ktime_get_ns() - t; + preempt_enable(); + kunit_info(test, "len=%zu: %llu MB/s", len, + div64_u64((u64)len * num_iters * 1000, t ?: 1)); + } +} -- cgit v1.3.1