diff options
Diffstat (limited to 'drivers/char/random.c')
| -rw-r--r-- | drivers/char/random.c | 33 |
1 files changed, 23 insertions, 10 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c index 87ab9f6b4..d72c6d14a 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -949,6 +949,7 @@ void add_interrupt_randomness(int irq, int irq_flags) /* award one bit for the contents of the fast pool */ credit_entropy_bits(r, credit + 1); } +EXPORT_SYMBOL_GPL(add_interrupt_randomness); #ifdef CONFIG_BLOCK void add_disk_randomness(struct gendisk *disk) @@ -1461,12 +1462,16 @@ random_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos) static ssize_t urandom_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos) { + static int maxwarn = 10; int ret; - if (unlikely(nonblocking_pool.initialized == 0)) - printk_once(KERN_NOTICE "random: %s urandom read " - "with %d bits of entropy available\n", - current->comm, nonblocking_pool.entropy_total); + if (unlikely(nonblocking_pool.initialized == 0) && + maxwarn > 0) { + maxwarn--; + printk(KERN_NOTICE "random: %s: uninitialized urandom read " + "(%zd bytes read, %d bits of entropy available)\n", + current->comm, nbytes, nonblocking_pool.entropy_total); + } nbytes = min_t(size_t, nbytes, INT_MAX >> (ENTROPY_SHIFT + 3)); ret = extract_entropy_user(&nonblocking_pool, buf, nbytes); @@ -1774,13 +1779,15 @@ int random_int_secret_init(void) return 0; } +static DEFINE_PER_CPU(__u32 [MD5_DIGEST_WORDS], get_random_int_hash) + __aligned(sizeof(unsigned long)); + /* * Get a random word for internal kernel use only. Similar to urandom but * with the goal of minimal entropy pool depletion. As a result, the random * value is not cryptographically secure but for several uses the cost of * depleting entropy is too high */ -static DEFINE_PER_CPU(__u32 [MD5_DIGEST_WORDS], get_random_int_hash); unsigned int get_random_int(void) { __u32 *hash; @@ -1850,12 +1857,18 @@ void add_hwgenerator_randomness(const char *buffer, size_t count, { struct entropy_store *poolp = &input_pool; - /* Suspend 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. - */ - wait_event_interruptible(random_write_wait, kthread_should_stop() || + if (unlikely(nonblocking_pool.initialized == 0)) + poolp = &nonblocking_pool; + else { + /* Suspend 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. + */ + wait_event_interruptible(random_write_wait, + kthread_should_stop() || ENTROPY_BITS(&input_pool) <= random_write_wakeup_bits); + } mix_pool_bytes(poolp, buffer, count); credit_entropy_bits(poolp, entropy); } |