crypto: algif_skcipher - set error code when kcalloc fails

Fix bug https://bugzilla.kernel.org/show_bug.cgi?id=188521. In function
skcipher_recvmsg_async(), variable err takes the return value, and its
value should be negative on failures. Because variable err may be
reassigned and checked before calling kcalloc(), its value may be 0
(indicates no error) even if kcalloc() fails. This patch fixes the bug
by explicitly assigning -ENOMEM to err when kcalloc() returns a NULL
pointer.

Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 3 insertions, 1 deletions

diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c
index 28556fce4267..bfb0a1a2507a 100644
--- a/crypto/algif_skcipher.c
+++ b/crypto/algif_skcipher.c
@@ -566,8 +566,10 @@ static int skcipher_recvmsg_async(struct socket *sock, struct msghdr *msg,
                          * need to expand */
                         tmp = kcalloc(tx_nents * 2, sizeof(*tmp),
                                       GFP_KERNEL);
-                        if (!tmp)
+                        if (!tmp) {
+                                err = -ENOMEM;
                                 goto free;
+                        }
 
                         sg_init_table(tmp, tx_nents * 2);
                         for (x = 0; x < tx_nents; x++)