[PATCH net-next] Fix unchecked dereference

From: Justin Iurman <justin.iurman@uliege.be>
To: dan.carpenter@oracle.com
Cc: kbuild@lists.01.org, justin.iurman@uliege.be,
	netdev@vger.kernel.org, lkp@intel.com, kbuild-all@lists.01.org,
	davem@davemloft.net
Subject: [PATCH net-next] Fix unchecked dereference
Date: Fri, 26 Jun 2020 10:54:35 +0200	[thread overview]
Message-ID: <20200626085435.6627-1-justin.iurman@uliege.be> (raw)
In-Reply-To: <20200625105237.GC2549@kadam>

If rhashtable_remove_fast returns an error, a rollback is applied. In
that case, an unchecked dereference has been fixed.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
---
 net/ipv6/ioam6.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/net/ipv6/ioam6.c b/net/ipv6/ioam6.c
index e414e915bf1e..f1347940245e 100644
--- a/net/ipv6/ioam6.c
+++ b/net/ipv6/ioam6.c
@@ -161,7 +161,8 @@ static int ioam6_genl_delns(struct sk_buff *skb, struct genl_info *info)
 	err = rhashtable_remove_fast(&nsdata->namespaces, &ns->head,
 				     rht_ns_params);
 	if (err) {
-		ns->schema->ns = ns;
+		if (ns->schema)
+			ns->schema->ns = ns;
 		goto out_unlock;
 	}
 
@@ -355,7 +356,8 @@ static int ioam6_genl_delsc(struct sk_buff *skb, struct genl_info *info)
 	err = rhashtable_remove_fast(&nsdata->schemas, &sc->head,
 				     rht_sc_params);
 	if (err) {
-		sc->ns->schema = sc;
+		if (sc->ns)
+			sc->ns->schema = sc;
 		goto out_unlock;
 	}
 
-- 
2.17.1

