Merge branch 'prandom'

prandom fixes/improvements

====================
It would be great if you could still consider this series that fixes and
improves prandom for 3.13. We have sent it to netdev as prandom() originally
came from net/core/utils.c and networking is its main user. For a detailled
description, please see individual patches.

For patch 3 in this series, there will be a minor merge conflict with the
random tree that is for 3.13. See below how to resolve it.

====
Hannes says: on merge with the random tree I would suggest to resolve the
conflict in drivers/char/random.c like this:

if (r->entropy_total > 128) {
	r->initialized = 1;
	r->entropy_total = 0;
	if (r == &nonblocking_pool) {
		prandom_reseed_late();
		pr_notice("random: %s pool is initialized\n",
			  r->name);
	}
}

So it won't generate a warning if DEBUG_RANDOM_BOOT gets activated.
====

Patch 1 should probably also go to -stable.

Set tested on 32 and 64 bit machines.

Thanks a lot!

Ref. original discussion: http://patchwork.ozlabs.org/patch/289951/
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 4 deletions

diff --git a/include/linux/random.h b/include/linux/random.h
index 6312dd9ba449..4002b3df4c85 100644
--- a/include/linux/random.h
+++ b/include/linux/random.h
@@ -29,8 +29,13 @@ unsigned long randomize_range(unsigned long start, unsigned long end, unsigned l
 u32 prandom_u32(void);
 void prandom_bytes(void *buf, int nbytes);
 void prandom_seed(u32 seed);
+void prandom_reseed_late(void);
 
-u32 prandom_u32_state(struct rnd_state *);
+struct rnd_state {
+	__u32 s1, s2, s3, s4;
+};
+
+u32 prandom_u32_state(struct rnd_state *state);
 void prandom_bytes_state(struct rnd_state *state, void *buf, int nbytes);
 
 /*
@@ -50,9 +55,10 @@ static inline void prandom_seed_state(struct rnd_state *state, u64 seed)
 {
 	u32 i = (seed >> 32) ^ (seed << 10) ^ seed;
 
-	state->s1 = __seed(i, 1);
-	state->s2 = __seed(i, 7);
-	state->s3 = __seed(i, 15);
+	state->s1 = __seed(i,   2U);
+	state->s2 = __seed(i,   8U);
+	state->s3 = __seed(i,  16U);
+	state->s4 = __seed(i, 128U);
 }
 
 #ifdef CONFIG_ARCH_RANDOM