[PATCH] random: remove use_input_pool parameter from crng_reseed()

From: Eric Biggers
Date: Fri Feb 04 2022 - 17:18:15 EST


From: Eric Biggers <ebiggers@xxxxxxxxxx>

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@xxxxxxxxxx>
---
drivers/char/random.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/char/random.c b/drivers/char/random.c
index e16cf254db15..964bce981235 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -371,7 +371,7 @@ 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
@@ -470,7 +470,7 @@ 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);
}

/*********************************************************************
@@ -707,7 +707,7 @@ 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;
@@ -716,7 +716,7 @@ 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);
@@ -756,7 +756,7 @@ 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);
@@ -1555,7 +1555,7 @@ 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:

base-commit: 4bccade22d405309cbc588094f956f4d310e4677
--
2.35.1