[PATCH 4.4 084/101] s390/crypto: unlock on error in prng_tdes_read()

From: Greg Kroah-Hartman
Date: Tue Jan 10 2017 - 08:42:39 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

commit 9e6e7c74315095fd40f41003850690c711e44420 upstream.

We added some new locking but forgot to unlock on error.

Fixes: 57127645d79d ("s390/zcrypt: Introduce new SHA-512 based Pseudo Random Generator.")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/s390/crypto/prng.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

--- a/arch/s390/crypto/prng.c
+++ b/arch/s390/crypto/prng.c
@@ -565,8 +565,10 @@ static ssize_t prng_tdes_read(struct fil
prng_data->prngws.byte_counter += n;
prng_data->prngws.reseed_counter += n;

- if (copy_to_user(ubuf, prng_data->buf, chunk))
- return -EFAULT;
+ if (copy_to_user(ubuf, prng_data->buf, chunk)) {
+ ret = -EFAULT;
+ break;
+ }

nbytes -= chunk;
ret += chunk;