diff options
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/random.c | 39 |
1 files changed, 22 insertions, 17 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c index 68613f0b6887..3404a91edf29 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -762,7 +762,7 @@ static bool crng_init_try_arch(struct crng_state *crng) return arch_init; } -static bool __init crng_init_try_arch_early(struct crng_state *crng) +static bool __init crng_init_try_arch_early(void) { int i; bool arch_init = true; @@ -774,7 +774,7 @@ static bool __init crng_init_try_arch_early(struct crng_state *crng) rv = random_get_entropy(); arch_init = false; } - crng->state[i] ^= rv; + primary_crng.state[i] ^= rv; } return arch_init; @@ -788,22 +788,20 @@ static void crng_initialize_secondary(struct crng_state *crng) crng->init_time = jiffies - CRNG_RESEED_INTERVAL - 1; } -static void __init crng_initialize_primary(struct crng_state *crng) +static void __init crng_initialize_primary(void) { - _extract_entropy(&crng->state[4], sizeof(u32) * 12); - if (crng_init_try_arch_early(crng) && trust_cpu && crng_init < 2) { + _extract_entropy(&primary_crng.state[4], sizeof(u32) * 12); + if (crng_init_try_arch_early() && trust_cpu && crng_init < 2) { invalidate_batched_entropy(); numa_crng_init(); crng_init = 2; pr_notice("crng init done (trusting CPU's manufacturer)\n"); } - crng->init_time = jiffies - CRNG_RESEED_INTERVAL - 1; + primary_crng.init_time = jiffies - CRNG_RESEED_INTERVAL - 1; } -static void crng_finalize_init(struct crng_state *crng) +static void crng_finalize_init(void) { - if (crng != &primary_crng || crng_init >= 2) - return; if (!system_wq) { /* We can't call numa_crng_init until we have workqueues, * so mark this for processing later. */ @@ -814,6 +812,7 @@ static void crng_finalize_init(struct crng_state *crng) invalidate_batched_entropy(); numa_crng_init(); crng_init = 2; + crng_need_final_init = false; process_random_ready_list(); wake_up_interruptible(&crng_init_wait); kill_fasync(&fasync, SIGIO, POLL_IN); @@ -980,7 +979,8 @@ static void crng_reseed(struct crng_state *crng, bool use_input_pool) memzero_explicit(&buf, sizeof(buf)); WRITE_ONCE(crng->init_time, jiffies); spin_unlock_irqrestore(&crng->lock, flags); - crng_finalize_init(crng); + if (crng == &primary_crng && crng_init < 2) + crng_finalize_init(); } static void _extract_crng(struct crng_state *crng, u8 out[CHACHA_BLOCK_SIZE]) @@ -1697,8 +1697,8 @@ int __init rand_initialize(void) { init_std_data(); if (crng_need_final_init) - crng_finalize_init(&primary_crng); - crng_initialize_primary(&primary_crng); + crng_finalize_init(); + crng_initialize_primary(); crng_global_init_time = jiffies; if (ratelimit_disable) { urandom_warning.interval = 0; @@ -1856,7 +1856,10 @@ static long random_ioctl(struct file *f, unsigned int cmd, unsigned long arg) */ if (!capable(CAP_SYS_ADMIN)) return -EPERM; - input_pool.entropy_count = 0; + if (xchg(&input_pool.entropy_count, 0) && random_write_wakeup_bits) { + wake_up_interruptible(&random_write_wait); + kill_fasync(&fasync, SIGIO, POLL_OUT); + } return 0; case RNDRESEEDCRNG: if (!capable(CAP_SYS_ADMIN)) @@ -2205,13 +2208,15 @@ void add_hwgenerator_randomness(const char *buffer, size_t count, return; } - /* Suspend writing if we're above the trickle threshold. + /* Throttle writing if we're above the trickle threshold. * We'll be woken up again once below random_write_wakeup_thresh, - * or when the calling thread is about to terminate. + * when the calling thread is about to terminate, or once + * CRNG_RESEED_INTERVAL has lapsed. */ - wait_event_interruptible(random_write_wait, + wait_event_interruptible_timeout(random_write_wait, !system_wq || kthread_should_stop() || - POOL_ENTROPY_BITS() <= random_write_wakeup_bits); + POOL_ENTROPY_BITS() <= random_write_wakeup_bits, + CRNG_RESEED_INTERVAL); mix_pool_bytes(buffer, count); credit_entropy_bits(entropy); } |