diff --git a/drivers/char/random.c b/drivers/char/random.c index 4cdf39567bae..3b83a6ac9f59 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -1020,12 +1020,6 @@ int __init rand_initialize(void) return 0; } -/* There is one of these per entropy source */ -struct timer_rand_state { - cycles_t last_time; - long last_delta, last_delta2; -}; - /* * Add device- or boot-specific data to the input pool to help * initialize it. @@ -1036,19 +1030,26 @@ struct timer_rand_state { */ void add_device_randomness(const void *buf, size_t size) { - unsigned long time = random_get_entropy() ^ jiffies; - unsigned long flags; + cycles_t cycles = random_get_entropy(); + unsigned long flags, now = jiffies; if (crng_init == 0 && size) crng_pre_init_inject(buf, size, false, false); spin_lock_irqsave(&input_pool.lock, flags); + _mix_pool_bytes(&cycles, sizeof(cycles)); + _mix_pool_bytes(&now, sizeof(now)); _mix_pool_bytes(buf, size); - _mix_pool_bytes(&time, sizeof(time)); spin_unlock_irqrestore(&input_pool.lock, flags); } EXPORT_SYMBOL(add_device_randomness); +/* There is one of these per entropy source */ +struct timer_rand_state { + unsigned long last_time; + long last_delta, last_delta2; +}; + /* * This function adds entropy to the entropy "pool" by using timing * delays. It uses the timer_rand_state structure to make an estimate @@ -1057,29 +1058,26 @@ EXPORT_SYMBOL(add_device_randomness); * The number "num" is also added to the pool - it should somehow describe * the type of event which just happened. This is currently 0-255 for * keyboard scan codes, and 256 upwards for interrupts. - * */ static void add_timer_randomness(struct timer_rand_state *state, unsigned int num) { - struct { - long jiffies; - unsigned int cycles; - unsigned int num; - } sample; + cycles_t cycles = random_get_entropy(); + unsigned long flags, now = jiffies; long delta, delta2, delta3; - sample.jiffies = jiffies; - sample.cycles = random_get_entropy(); - sample.num = num; - mix_pool_bytes(&sample, sizeof(sample)); + spin_lock_irqsave(&input_pool.lock, flags); + _mix_pool_bytes(&cycles, sizeof(cycles)); + _mix_pool_bytes(&now, sizeof(now)); + _mix_pool_bytes(&num, sizeof(num)); + spin_unlock_irqrestore(&input_pool.lock, flags); /* * Calculate number of bits of randomness we probably added. * We take into account the first, second and third-order deltas * in order to make our estimate. */ - delta = sample.jiffies - READ_ONCE(state->last_time); - WRITE_ONCE(state->last_time, sample.jiffies); + delta = now - READ_ONCE(state->last_time); + WRITE_ONCE(state->last_time, now); delta2 = delta - READ_ONCE(state->last_delta); WRITE_ONCE(state->last_delta, delta); @@ -1305,10 +1303,10 @@ static void mix_interrupt_randomness(struct work_struct *work) void add_interrupt_randomness(int irq) { enum { MIX_INFLIGHT = 1U << 31 }; + cycles_t cycles = random_get_entropy(); + unsigned long now = jiffies; struct fast_pool *fast_pool = this_cpu_ptr(&irq_randomness); struct pt_regs *regs = get_irq_regs(); - unsigned long now = jiffies; - cycles_t cycles = random_get_entropy(); unsigned int new_count; if (cycles == 0) @@ -1383,28 +1381,28 @@ static void entropy_timer(struct timer_list *t) static void try_to_generate_entropy(void) { struct { - unsigned long now; + cycles_t cycles; struct timer_list timer; } stack; - stack.now = random_get_entropy(); + stack.cycles = random_get_entropy(); /* Slow counter - or none. Don't even bother */ - if (stack.now == random_get_entropy()) + if (stack.cycles == random_get_entropy()) return; timer_setup_on_stack(&stack.timer, entropy_timer, 0); while (!crng_ready()) { if (!timer_pending(&stack.timer)) mod_timer(&stack.timer, jiffies + 1); - mix_pool_bytes(&stack.now, sizeof(stack.now)); + mix_pool_bytes(&stack.cycles, sizeof(stack.cycles)); schedule(); - stack.now = random_get_entropy(); + stack.cycles = random_get_entropy(); } del_timer_sync(&stack.timer); destroy_timer_on_stack(&stack.timer); - mix_pool_bytes(&stack.now, sizeof(stack.now)); + mix_pool_bytes(&stack.cycles, sizeof(stack.cycles)); }