diff options
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/random.c | 43 |
1 files changed, 4 insertions, 39 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c index 7d1682ea1e86..6e455bc4a39e 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -910,12 +910,13 @@ void add_interrupt_randomness(int irq, int irq_flags) /* * If we have architectural seed generator, produce a seed and - * add it to the pool. For the sake of paranoia count it as - * 50% entropic. + * add it to the pool. For the sake of paranoia don't let the + * architectural seed generator dominate the input from the + * interrupt noise. */ if (arch_get_random_seed_long(&seed)) { __mix_pool_bytes(r, &seed, sizeof(seed)); - credit += sizeof(seed) * 4; + credit = 1; } spin_unlock(&r->lock); @@ -1328,37 +1329,6 @@ void rand_initialize_disk(struct gendisk *disk) } #endif -/* - * Attempt an emergency refill using arch_get_random_seed_long(). - * - * As with add_interrupt_randomness() be paranoid and only - * credit the output as 50% entropic. - */ -static int arch_random_refill(void) -{ - const unsigned int nlongs = 64; /* Arbitrary number */ - unsigned int n = 0; - unsigned int i; - unsigned long buf[nlongs]; - - if (!arch_has_random_seed()) - return 0; - - for (i = 0; i < nlongs; i++) { - if (arch_get_random_seed_long(&buf[n])) - n++; - } - - if (n) { - unsigned int rand_bytes = n * sizeof(unsigned long); - - mix_pool_bytes(&input_pool, buf, rand_bytes); - credit_entropy_bits(&input_pool, rand_bytes*4); - } - - return n; -} - static ssize_t _random_read(int nonblock, char __user *buf, size_t nbytes) { @@ -1379,11 +1349,6 @@ _random_read(int nonblock, char __user *buf, size_t nbytes) return n; /* Pool is (near) empty. Maybe wait and retry. */ - - /* First try an emergency refill */ - if (arch_random_refill()) - continue; - if (nonblock) return -EAGAIN; |