spi: bcm-qspi: Fix use after free in bcm_qspi_probe() in error path
[sfrench/cifs-2.6.git] / net / nsh / nsh.c
1 /*
2  * Network Service Header
3  *
4  * Copyright (c) 2017 Red Hat, Inc. -- Jiri Benc <jbenc@redhat.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10
11 #include <linux/module.h>
12 #include <linux/netdevice.h>
13 #include <linux/skbuff.h>
14 #include <net/nsh.h>
15 #include <net/tun_proto.h>
16
17 static struct sk_buff *nsh_gso_segment(struct sk_buff *skb,
18                                        netdev_features_t features)
19 {
20         struct sk_buff *segs = ERR_PTR(-EINVAL);
21         unsigned int nsh_len, mac_len;
22         __be16 proto;
23         int nhoff;
24
25         skb_reset_network_header(skb);
26
27         nhoff = skb->network_header - skb->mac_header;
28         mac_len = skb->mac_len;
29
30         if (unlikely(!pskb_may_pull(skb, NSH_BASE_HDR_LEN)))
31                 goto out;
32         nsh_len = nsh_hdr_len(nsh_hdr(skb));
33         if (unlikely(!pskb_may_pull(skb, nsh_len)))
34                 goto out;
35
36         proto = tun_p_to_eth_p(nsh_hdr(skb)->np);
37         if (!proto)
38                 goto out;
39
40         __skb_pull(skb, nsh_len);
41
42         skb_reset_mac_header(skb);
43         skb_reset_mac_len(skb);
44         skb->protocol = proto;
45
46         features &= NETIF_F_SG;
47         segs = skb_mac_gso_segment(skb, features);
48         if (IS_ERR_OR_NULL(segs)) {
49                 skb_gso_error_unwind(skb, htons(ETH_P_NSH), nsh_len,
50                                      skb->network_header - nhoff,
51                                      mac_len);
52                 goto out;
53         }
54
55         for (skb = segs; skb; skb = skb->next) {
56                 skb->protocol = htons(ETH_P_NSH);
57                 __skb_push(skb, nsh_len);
58                 skb_set_mac_header(skb, -nhoff);
59                 skb->network_header = skb->mac_header + mac_len;
60                 skb->mac_len = mac_len;
61         }
62
63 out:
64         return segs;
65 }
66
67 static struct packet_offload nsh_packet_offload __read_mostly = {
68         .type = htons(ETH_P_NSH),
69         .priority = 15,
70         .callbacks = {
71                 .gso_segment = nsh_gso_segment,
72         },
73 };
74
75 static int __init nsh_init_module(void)
76 {
77         dev_add_offload(&nsh_packet_offload);
78         return 0;
79 }
80
81 static void __exit nsh_cleanup_module(void)
82 {
83         dev_remove_offload(&nsh_packet_offload);
84 }
85
86 module_init(nsh_init_module);
87 module_exit(nsh_cleanup_module);
88
89 MODULE_AUTHOR("Jiri Benc <jbenc@redhat.com>");
90 MODULE_DESCRIPTION("NSH protocol");
91 MODULE_LICENSE("GPL v2");