random: only call crng_finalize_init() for primary_crng

commit 9d5505f1eebeca778074a0260ed077fd85f8792c upstream.

crng_finalize_init() returns instantly if it is called for another pool
than primary_crng. The test whether crng_finalize_init() is still required
can be moved to the relevant caller in crng_reseed(), and
crng_need_final_init can be reset to false if crng_finalize_init() is
called with workqueues ready. Then, no previous callsite will call
crng_finalize_init() unless it is needed, and we can get rid of the
superfluous function parameter.

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/char/random.c b/drivers/char/random.c
index 0685e64..6c3eee2 100644 (file)
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -800,10 +800,8 @@ static void __init crng_initialize_primary(void)
        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])
@@ -1697,7 +1697,7 @@ int __init rand_initialize(void)
 {
        init_std_data();
        if (crng_need_final_init)
-               crng_finalize_init(&primary_crng);
+               crng_finalize_init();
        crng_initialize_primary();
        crng_global_init_time = jiffies;
        if (ratelimit_disable) {