1 files changed, 24 insertions, 11 deletions

diff --git a/fs/ubifs/replay.c b/fs/ubifs/replay.c
index 75f961c4c044..a08c5b7030ea 100644
--- a/fs/ubifs/replay.c
+++ b/fs/ubifs/replay.c
@@ -533,6 +533,28 @@ static int is_last_bud(struct ubifs_info *c, struct ubifs_bud *bud)
 	return data == 0xFFFFFFFF;
 }
 
+/* authenticate_sleb_hash and authenticate_sleb_hmac are split out for stack usage */
+static int authenticate_sleb_hash(struct ubifs_info *c, struct shash_desc *log_hash, u8 *hash)
+{
+	SHASH_DESC_ON_STACK(hash_desc, c->hash_tfm);
+
+	hash_desc->tfm = c->hash_tfm;
+	hash_desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+
+	ubifs_shash_copy_state(c, log_hash, hash_desc);
+	return crypto_shash_final(hash_desc, hash);
+}
+
+static int authenticate_sleb_hmac(struct ubifs_info *c, u8 *hash, u8 *hmac)
+{
+	SHASH_DESC_ON_STACK(hmac_desc, c->hmac_tfm);
+
+	hmac_desc->tfm = c->hmac_tfm;
+	hmac_desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+
+	return crypto_shash_digest(hmac_desc, hash, c->hash_len, hmac);
+}
+
 /**
  * authenticate_sleb - authenticate one scan LEB
  * @c: UBIFS file-system description object
@@ -574,21 +596,12 @@ static int authenticate_sleb(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
 
 		if (snod->type == UBIFS_AUTH_NODE) {
 			struct ubifs_auth_node *auth = snod->node;
-			SHASH_DESC_ON_STACK(hash_desc, c->hash_tfm);
-			SHASH_DESC_ON_STACK(hmac_desc, c->hmac_tfm);
-
-			hash_desc->tfm = c->hash_tfm;
-			hash_desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
 
-			ubifs_shash_copy_state(c, log_hash, hash_desc);
-			err = crypto_shash_final(hash_desc, hash);
+			err = authenticate_sleb_hash(c, log_hash, hash);
 			if (err)
 				goto out;
 
-			hmac_desc->tfm = c->hmac_tfm;
-			hmac_desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
-			err = crypto_shash_digest(hmac_desc, hash, c->hash_len,
-						  hmac);
+			err = authenticate_sleb_hmac(c, hash, hmac);
 			if (err)
 				goto out;