From b182ac00aa60d1b61d92d70ea399cd39f966fb31 Mon Sep 17 00:00:00 2001
From: cao <cao.xuewen@zte.com.cn>
Date: Tue, 1 Nov 2016 07:23:56 +0800
Subject: [PATCH] Fix coverity defects: CID 152975

CID 152975: Type:Dereference null return value

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: cao.xuewen <cao.xuewen@zte.com.cn>
Closes #5322
---
 module/zfs/dmu.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/module/zfs/dmu.c b/module/zfs/dmu.c
index 7da49af7b5f1..a817fdbcefe1 100644
--- a/module/zfs/dmu.c
+++ b/module/zfs/dmu.c
@@ -369,12 +369,17 @@ dmu_spill_hold_by_dnode(dnode_t *dn, uint32_t flags, void *tag, dmu_buf_t **dbp)
 	if ((flags & DB_RF_HAVESTRUCT) == 0)
 		rw_exit(&dn->dn_struct_rwlock);
 
-	ASSERT(db != NULL);
+	if (db == NULL) {
+		*dbp = NULL;
+		return (SET_ERROR(EIO));
+	}
 	err = dbuf_read(db, NULL, flags);
 	if (err == 0)
 		*dbp = &db->db;
-	else
+	else {
 		dbuf_rele(db, tag);
+		*dbp = NULL;
+	}
 	return (err);
 }