[PATCH 5.17 008/111] random: remove use_input_pool parameter from crng_reseed()

Greg Kroah-Hartman
2022-05-27T08:59:22Z

From: Eric Biggers <ebiggers@google.com>

commit 5d58ea3a31cc98b9fa563f6921d3d043bf0103d1 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/char/random.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -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 nbit
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,
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_stat
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_st
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,
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;