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From:   Peilin Ye <yepeilin.cs@gmail.com>
To:     Wensong Zhang <wensong@linux-vs.org>,
        Simon Horman <horms@verge.net.au>, Julian Anastasov <ja@ssi.bg>
Cc:     Peilin Ye <yepeilin.cs@gmail.com>,
        Pablo Neira Ayuso <pablo@netfilter.org>,
        Jozsef Kadlecsik <kadlec@netfilter.org>,
        Florian Westphal <fw@strlen.de>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        netdev@vger.kernel.org, lvs-devel@vger.kernel.org,
        netfilter-devel@vger.kernel.org, coreteam@netfilter.org,
        linux-kernel-mentees@lists.linuxfoundation.org,
        syzkaller-bugs@googlegroups.com, linux-kernel@vger.kernel.org
Subject: [Linux-kernel-mentees] [PATCH net] ipvs: Fix uninit-value in do_ip_vs_set_ctl()
Date:   Mon, 10 Aug 2020 18:07:03 -0400
Message-Id: <20200810220703.796718-1-yepeilin.cs@gmail.com>
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do_ip_vs_set_ctl() is referencing uninitialized stack value when `len` is
zero. Fix it.

Reported-and-tested-by: syzbot+23b5f9e7caf61d9a3898@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?id=46ebfb92a8a812621a001ef04d90dfa459520fe2
Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
---
 net/netfilter/ipvs/ip_vs_ctl.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
index 412656c34f20..c050b6a42786 100644
--- a/net/netfilter/ipvs/ip_vs_ctl.c
+++ b/net/netfilter/ipvs/ip_vs_ctl.c
@@ -2418,7 +2418,7 @@ do_ip_vs_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len)
 {
 	struct net *net = sock_net(sk);
 	int ret;
-	unsigned char arg[MAX_SET_ARGLEN];
+	unsigned char arg[MAX_SET_ARGLEN] = {};
 	struct ip_vs_service_user *usvc_compat;
 	struct ip_vs_service_user_kern usvc;
 	struct ip_vs_service *svc;
-- 
2.25.1