crypto: pcrypt - Dont calulate a callback cpu on empty callback cpumask

If the callback cpumask is empty, we crash with a division by zero
when we try to calculate a callback cpu. So we don't update the callback
cpu in pcrypt_do_parallel if the callback cpumask is empty.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 3 insertions, 0 deletions

diff --git a/crypto/pcrypt.c b/crypto/pcrypt.c
index 7153a50bce27..794c172b99f7 100644
--- a/crypto/pcrypt.c
+++ b/crypto/pcrypt.c
@@ -82,6 +82,9 @@ static int pcrypt_do_parallel(struct padata_priv *padata, unsigned int *cb_cpu,
         if (cpumask_test_cpu(cpu, cpumask->mask))
                         goto out;
 
+        if (!cpumask_weight(cpumask->mask))
+                        goto out;
+
         cpu_index = cpu % cpumask_weight(cpumask->mask);
 
         cpu = cpumask_first(cpumask->mask);