From: Dan Carpenter <dan.carpenter@oracle.com>
Subject: [patch] s390/crypto: unlock on error in prng_tdes_read()
Date: Fri, 18 Nov 2016 14:11:00 +0300
Message-ID: <20161118105451.GA26523@mwanda>
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Cc: "David S. Miller" <davem@davemloft.net>,
        Martin Schwidefsky <schwidefsky@de.ibm.com>,
        Heiko Carstens <heiko.carstens@de.ibm.com>,
        linux-crypto@vger.kernel.org, linux-s390@vger.kernel.org,
        kernel-janitors@vger.kernel.org
To: Herbert Xu <herbert@gondor.apana.org.au>,
        Harald Freudenberger <freude@linux.vnet.ibm.com>
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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@oracle.com>

diff --git a/arch/s390/crypto/prng.c b/arch/s390/crypto/prng.c
index 9cc050f..1113389 100644
--- a/arch/s390/crypto/prng.c
+++ b/arch/s390/crypto/prng.c
@@ -507,8 +507,10 @@ static ssize_t prng_tdes_read(struct file *file, char __user *ubuf,
 		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;