Hello Vinay Kumar Yadav,
The patch 9819f22c410b: "chelsio/chtls: Fix panic when listen on
multiadapter" from Oct 19, 2020, leads to the following static
checker warning:
drivers/net/ethernet/chelsio/inline_crypto/chtls/chtls_cm.c:137 chtls_find_netdev()
warn: 'ndev' held on error path.
drivers/net/ethernet/chelsio/inline_crypto/chtls/chtls_cm.c
92 static struct net_device *chtls_find_netdev(struct chtls_dev *cdev,
93 struct sock *sk)
94 {
95 struct adapter *adap = pci_get_drvdata(cdev->pdev);
96 struct net_device *ndev = cdev->ports[0];
^^^^^^^^^^^^^^^^^^^^^
The reference counting in this function is pretty confusing. I would
have expected it to take a dev_hold() reference on all paths before
returning.
No dev_hold() here, though.
97 #if IS_ENABLED(CONFIG_IPV6)
98 struct net_device *temp;
99 int addr_type;
100 #endif
101 int i;
102
103 switch (sk->sk_family) {
104 case PF_INET:
105 if (likely(!inet_sk(sk)->inet_rcv_saddr))
106 return ndev;
107 ndev = __ip_dev_find(&init_net, inet_sk(sk)->inet_rcv_saddr, false);
__ip_dev_find call dev_hold()
108 break;
109 #if IS_ENABLED(CONFIG_IPV6)
110 case PF_INET6:
111 addr_type = ipv6_addr_type(&sk->sk_v6_rcv_saddr);
112 if (likely(addr_type == IPV6_ADDR_ANY))
113 return ndev;
114
115 for_each_netdev_rcu(&init_net, temp) {
116 if (ipv6_chk_addr(&init_net, (struct in6_addr *)
117 &sk->sk_v6_rcv_saddr, temp, 1)) {
118 ndev = temp;
No dev_hold().
119 break;
120 }
121 }
122 break;
123 #endif
124 default:
125 return NULL;
126 }
127
128 if (!ndev)
129 return NULL;
130
131 if (is_vlan_dev(ndev))
132 ndev = vlan_dev_real_dev(ndev);
133
134 for_each_port(adap, i)
135 if (cdev->ports[i] == ndev)
136 return ndev;
^^^^^^^^^^^
We're holding dev_hold() for ipv4 but not for ipv6.
137 return NULL;
^^^^^^^^^^^^
Smatch complains that if we hit this for ipv4 then we're leaking a
dev_hold() reference.
138 }
regards,
dan carpenter
