random: remove use_input_pool parameter from crng_reseed()
authorEric Biggers <ebiggers@google.com>
Fri, 4 Feb 2022 22:17:33 +0000 (14:17 -0800)
committerJason A. Donenfeld <Jason@zx2c4.com>
Mon, 21 Feb 2022 15:48:06 +0000 (16:48 +0100)
The primary_crng is always reseeded from the input_pool, while the NUMA
crngs are always reseeded from the primary_crng.  Remove the redundant
'use_input_pool' parameter from crng_reseed() and just directly check
whether the crng is the primary_crng.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
drivers/char/random.c

index 92aca0a..968c415 100644 (file)
@@ -365,7 +365,7 @@ static struct {
 
 static void extract_entropy(void *buf, size_t nbytes);
 
-static void crng_reseed(struct crng_state *crng, bool use_input_pool);
+static void crng_reseed(struct crng_state *crng);
 
 /*
  * This function adds bytes into the entropy "pool".  It does not
@@ -464,7 +464,7 @@ static void credit_entropy_bits(int nbits)
        trace_credit_entropy_bits(nbits, entropy_count, _RET_IP_);
 
        if (crng_init < 2 && entropy_count >= POOL_MIN_BITS)
-               crng_reseed(&primary_crng, true);
+               crng_reseed(&primary_crng);
 }
 
 /*********************************************************************
@@ -701,7 +701,7 @@ static int crng_slow_load(const u8 *cp, size_t len)
        return 1;
 }
 
-static void crng_reseed(struct crng_state *crng, bool use_input_pool)
+static void crng_reseed(struct crng_state *crng)
 {
        unsigned long flags;
        int i;
@@ -710,7 +710,7 @@ static void crng_reseed(struct crng_state *crng, bool use_input_pool)
                u32 key[8];
        } buf;
 
-       if (use_input_pool) {
+       if (crng == &primary_crng) {
                int entropy_count;
                do {
                        entropy_count = READ_ONCE(input_pool.entropy_count);
@@ -748,7 +748,7 @@ static void _extract_crng(struct crng_state *crng, u8 out[CHACHA_BLOCK_SIZE])
                init_time = READ_ONCE(crng->init_time);
                if (time_after(READ_ONCE(crng_global_init_time), init_time) ||
                    time_after(jiffies, init_time + CRNG_RESEED_INTERVAL))
-                       crng_reseed(crng, crng == &primary_crng);
+                       crng_reseed(crng);
        }
        spin_lock_irqsave(&crng->lock, flags);
        chacha20_block(&crng->state[0], out);
@@ -1547,7 +1547,7 @@ static long random_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
                        return -EPERM;
                if (crng_init < 2)
                        return -ENODATA;
-               crng_reseed(&primary_crng, true);
+               crng_reseed(&primary_crng);
                WRITE_ONCE(crng_global_init_time, jiffies - 1);
                return 0;
        default: