From d152fcc173149a99d6f707a5b8a80d83d906755b Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Thu, 12 Apr 2018 00:50:45 -0400 Subject: [PATCH] random: crng_reseed() should lock the crng instance that it is modifying commit 0bb29a849a6433b72e249eea7695477b02056e94 upstream. Reported-by: Jann Horn Fixes: 1e7f583af67b ("random: make /dev/urandom scalable for silly...") Cc: stable@kernel.org # 4.8+ Signed-off-by: Theodore Ts'o Reviewed-by: Jann Horn Signed-off-by: Greg Kroah-Hartman --- drivers/char/random.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/char/random.c b/drivers/char/random.c index d64aebe7ecf3..c621f8443281 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -879,7 +879,7 @@ static void crng_reseed(struct crng_state *crng, struct entropy_store *r) _crng_backtrack_protect(&primary_crng, buf.block, CHACHA20_KEY_SIZE); } - spin_lock_irqsave(&primary_crng.lock, flags); + spin_lock_irqsave(&crng->lock, flags); for (i = 0; i < 8; i++) { unsigned long rv; if (!arch_get_random_seed_long(&rv) && @@ -889,7 +889,7 @@ static void crng_reseed(struct crng_state *crng, struct entropy_store *r) } memzero_explicit(&buf, sizeof(buf)); crng->init_time = jiffies; - spin_unlock_irqrestore(&primary_crng.lock, flags); + spin_unlock_irqrestore(&crng->lock, flags); if (crng == &primary_crng && crng_init < 2) { invalidate_batched_entropy(); crng_init = 2; -- 2.20.1