diff options
Diffstat (limited to 'drivers/char/random.c')
| -rw-r--r-- | drivers/char/random.c | 57 |
1 files changed, 37 insertions, 20 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c index e3dd1dd3dd22..79d7d4e4e582 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -229,7 +229,7 @@ static void crng_reseed(void) /* * This generates a ChaCha block using the provided key, and then - * immediately overwites that key with half the block. It returns + * immediately overwrites that key with half the block. It returns * the resultant ChaCha state to the user, along with the second * half of the block containing 32 bytes of random data that may * be used; random_data_len may not be greater than 32. @@ -596,12 +596,20 @@ static void extract_entropy(void *buf, size_t len) unsigned long rdseed[32 / sizeof(long)]; size_t counter; } block; - size_t i; + size_t i, longs; - for (i = 0; i < ARRAY_SIZE(block.rdseed); ++i) { - if (!arch_get_random_seed_long(&block.rdseed[i]) && - !arch_get_random_long(&block.rdseed[i])) - block.rdseed[i] = random_get_entropy(); + for (i = 0; i < ARRAY_SIZE(block.rdseed);) { + longs = arch_get_random_seed_longs(&block.rdseed[i], ARRAY_SIZE(block.rdseed) - i); + if (longs) { + i += longs; + continue; + } + longs = arch_get_random_longs(&block.rdseed[i], ARRAY_SIZE(block.rdseed) - i); + if (longs) { + i += longs; + continue; + } + block.rdseed[i++] = random_get_entropy(); } spin_lock_irqsave(&input_pool.lock, flags); @@ -643,10 +651,10 @@ static void __cold _credit_init_bits(size_t bits) add = min_t(size_t, bits, POOL_BITS); + orig = READ_ONCE(input_pool.init_bits); do { - orig = READ_ONCE(input_pool.init_bits); new = min_t(unsigned int, POOL_BITS, orig + add); - } while (cmpxchg(&input_pool.init_bits, orig, new) != orig); + } while (!try_cmpxchg(&input_pool.init_bits, &orig, new)); if (orig < POOL_READY_BITS && new >= POOL_READY_BITS) { crng_reseed(); /* Sets crng_init to CRNG_READY under base_crng.lock. */ @@ -755,8 +763,8 @@ static int random_pm_notification(struct notifier_block *nb, unsigned long actio spin_unlock_irqrestore(&input_pool.lock, flags); if (crng_ready() && (action == PM_RESTORE_PREPARE || - (action == PM_POST_SUSPEND && - !IS_ENABLED(CONFIG_PM_AUTOSLEEP) && !IS_ENABLED(CONFIG_ANDROID)))) { + (action == PM_POST_SUSPEND && !IS_ENABLED(CONFIG_PM_AUTOSLEEP) && + !IS_ENABLED(CONFIG_PM_USERSPACE_AUTOSLEEP)))) { crng_reseed(); pr_notice("crng reseeded on system resumption\n"); } @@ -776,22 +784,31 @@ static struct notifier_block pm_notifier = { .notifier_call = random_pm_notifica int __init random_init(const char *command_line) { ktime_t now = ktime_get_real(); - unsigned int i, arch_bits; - unsigned long entropy; + size_t i, longs, arch_bits; + unsigned long entropy[BLAKE2S_BLOCK_SIZE / sizeof(long)]; #if defined(LATENT_ENTROPY_PLUGIN) static const u8 compiletime_seed[BLAKE2S_BLOCK_SIZE] __initconst __latent_entropy; _mix_pool_bytes(compiletime_seed, sizeof(compiletime_seed)); #endif - for (i = 0, arch_bits = BLAKE2S_BLOCK_SIZE * 8; - i < BLAKE2S_BLOCK_SIZE; i += sizeof(entropy)) { - if (!arch_get_random_seed_long_early(&entropy) && - !arch_get_random_long_early(&entropy)) { - entropy = random_get_entropy(); - arch_bits -= sizeof(entropy) * 8; + for (i = 0, arch_bits = sizeof(entropy) * 8; i < ARRAY_SIZE(entropy);) { + longs = arch_get_random_seed_longs(entropy, ARRAY_SIZE(entropy) - i); + if (longs) { + _mix_pool_bytes(entropy, sizeof(*entropy) * longs); + i += longs; + continue; } - _mix_pool_bytes(&entropy, sizeof(entropy)); + longs = arch_get_random_longs(entropy, ARRAY_SIZE(entropy) - i); + if (longs) { + _mix_pool_bytes(entropy, sizeof(*entropy) * longs); + i += longs; + continue; + } + entropy[0] = random_get_entropy(); + _mix_pool_bytes(entropy, sizeof(*entropy)); + arch_bits -= sizeof(*entropy) * 8; + ++i; } _mix_pool_bytes(&now, sizeof(now)); _mix_pool_bytes(utsname(), sizeof(*(utsname()))); @@ -1174,7 +1191,7 @@ static void __cold entropy_timer(struct timer_list *timer) */ static void __cold try_to_generate_entropy(void) { - enum { NUM_TRIAL_SAMPLES = 8192, MAX_SAMPLES_PER_BIT = 32 }; + enum { NUM_TRIAL_SAMPLES = 8192, MAX_SAMPLES_PER_BIT = HZ / 30 }; struct entropy_timer_state stack; unsigned int i, num_different = 0; unsigned long last = random_get_entropy(); |