[PATCH] crypto: drbg: check the return value of crypto_shash_init()

[Jia-Ju Bai <baijiaju1990@gmail.com>]

Then function crypto_shash_init() in drbg_kcapi_hash() can fail, but
there is no check of its return value. To fix this bug, its return value
should be checked with new error handling code.

Fixes: 541af946fe13 ("crypto: drbg - SP800-90A Deterministic Random Bit Generator")
Reported-by: TOTE Robot <oslab@tsinghua.edu.cn>
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
---
 crypto/drbg.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/crypto/drbg.c b/crypto/drbg.c
index 177983b6ae38..51feb9538701 100644
--- a/crypto/drbg.c
+++ b/crypto/drbg.c
@@ -1725,8 +1725,11 @@ static int drbg_kcapi_hash(struct drbg_state *drbg, unsigned char *outval,
 {
 	struct sdesc *sdesc = (struct sdesc *)drbg->priv_data;
 	struct drbg_string *input = NULL;
+	int ret = 0;
 
-	crypto_shash_init(&sdesc->shash);
+	ret = crypto_shash_init(&sdesc->shash);
+	if (ret)
+		return ret;
 	list_for_each_entry(input, in, list)
 		crypto_shash_update(&sdesc->shash, input->buf, input->len);
 	return crypto_shash_final(&sdesc->shash, outval);
-- 
2.17.1