/*
 * netsniff-ng - the packet sniffing beast
 * Copyright 2009, 2010 Daniel Borkmann.
 * Subject to the GPL, version 2.
 */

#include <stdint.h>
#include <netinet/in.h>    /* for ntohs() */

#include "proto.h"
#include "protos.h"
#include "dissector_eth.h"
#include "pkt_buff.h"
#include "built_in.h"

struct arphdr {
	uint16_t ar_hrd;   /* format of hardware address */
	uint16_t ar_pro;   /* format of protocol address */
	uint8_t ar_hln;    /* length of hardware address */
	uint8_t ar_pln;    /* length of protocol address */
	uint16_t ar_op;    /* ARP opcode (command)       */
	uint8_t ar_sha[6]; /* sender hardware address    */
	uint8_t ar_sip[4]; /* sender IP address          */
	uint8_t ar_tha[6]; /* target hardware address    */
	uint8_t ar_tip[4]; /* target IP address          */
} __packed;

#define ARPHRD_ETHER	1
#define ARPHRD_IEEE802	6
#define ARPHRD_ARCNET	7
#define ARPHRD_ATM	16
#define ARPHRD_ATM2	19
#define ARPHRD_SERIAL	20
#define ARPHRD_ATM3	21
#define ARPHRD_IEEE1394	24

#define ARPOP_REQUEST   1  /* ARP request                */
#define ARPOP_REPLY     2  /* ARP reply                  */
#define ARPOP_RREQUEST  3  /* RARP request               */
#define ARPOP_RREPLY    4  /* RARP reply                 */
#define ARPOP_InREQUEST 8  /* InARP request              */
#define ARPOP_InREPLY   9  /* InARP reply                */
#define ARPOP_NAK       10 /* (ATM)ARP NAK               */

static void arp(struct pkt_buff *pkt)
{
	char *hrd;
	char *pro;
	char *opcode;
	struct arphdr *arp = (struct arphdr *) pkt_pull(pkt, sizeof(*arp));

	if (arp == NULL)
		return;

	switch (ntohs(arp->ar_hrd)) {
	case ARPHRD_ETHER:
		hrd = "Ethernet";
		break;
	case ARPHRD_IEEE802:
		hrd = "IEEE 802";
		break;
	case ARPHRD_ARCNET:
		hrd = "ARCNET";
		break;
	case ARPHRD_ATM:
	case ARPHRD_ATM2:
	case ARPHRD_ATM3:
		hrd = "ATM";
		break;
	case ARPHRD_SERIAL:
		hrd = "Serial Line";
		break;
	case ARPHRD_IEEE1394:
		hrd = "IEEE 1394.1995";
		break;
	default:
		hrd = "Unknown";
		break;
	}

	pro = lookup_ether_type(ntohs(arp->ar_pro));
	if (pro == NULL)
		pro = "Unknown";

	switch (ntohs(arp->ar_op)) {
	case ARPOP_REQUEST:
		opcode = "ARP request";
		break;
	case ARPOP_REPLY:
		opcode = "ARP reply";
		break;
	case ARPOP_RREQUEST:
		opcode = "RARP request";
		break;
	case ARPOP_RREPLY:
		opcode = "RARP reply";
		break;
	case ARPOP_InREQUEST:
		opcode = "InARP request";
		break;
	case ARPOP_InREPLY:
		opcode = "InARP reply";
		break;
	case ARPOP_NAK:
		opcode = "(ATM) ARP NAK";
		break;
	default:
		opcode = "Unknown";
		break;
	};

	tprintf(" [ ARP ");
	tprintf("Format HA (%u => %s), ", ntohs(arp->ar_hrd), hrd);
	tprintf("Format Proto (0x%.4x => %s), ", ntohs(arp->ar_pro), pro);
	tprintf("HA Len (%u), ", arp->ar_hln);
	tprintf("Proto Len (%u), ", arp->ar_pln);
	tprintf("Opcode (%u => %s)", ntohs(arp->ar_op), opcode);
	tprintf(" ]\n");
}

static void arp_less(struct pkt_buff *pkt)
{
	char *opcode = NULL;
	struct arphdr *arp = (struct arphdr *) pkt_pull(pkt, sizeof(*arp));

	if (arp == NULL)
		return;

	switch (ntohs(arp->ar_op)) {
	case ARPOP_REQUEST:
		opcode = "ARP request";
		break;
	case ARPOP_REPLY:
		opcode = "ARP reply";
		break;
	case ARPOP_RREQUEST:
		opcode = "RARP request";
		break;
	case ARPOP_RREPLY:
		opcode = "RARP reply";
		break;
	case ARPOP_InREQUEST:
		opcode = "InARP request";
		break;
	case ARPOP_InREPLY:
		opcode = "InARP reply";
		break;
	case ARPOP_NAK:
		opcode = "(ATM) ARP NAK";
		break;
	default:
		opcode = "Unknown";
		break;
	};

	tprintf(" Op %s", opcode);
}

struct protocol arp_ops = {
	.key = 0x0806,
	.print_full = arp,
	.print_less = arp_less,
};
>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Robert Shearman &lt;rshearma@brocade.com&gt;</td><td class='right'>2017-01-24 16:26:48 +0000</td></tr>
<tr><th>committer</th><td>David S. Miller &lt;davem@davemloft.net&gt;</td><td class='right'>2017-01-24 16:21:36 -0500</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?h=nds-private-remove&amp;id=85c814016ce3b371016c2c054a905fa2492f5a65'>85c814016ce3b371016c2c054a905fa2492f5a65</a> (<a href='/cgit.cgi/linux/net-next.git/patch/?id=85c814016ce3b371016c2c054a905fa2492f5a65'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?h=nds-private-remove&amp;id=85c814016ce3b371016c2c054a905fa2492f5a65'>c9c7eb5576834cae05dba40e82ca84a7772b7a51</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?h=nds-private-remove&amp;id=88ff7334f25909802140e690c0e16433e485b0a0'>88ff7334f25909802140e690c0e16433e485b0a0</a> (<a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=85c814016ce3b371016c2c054a905fa2492f5a65&amp;id2=88ff7334f25909802140e690c0e16433e485b0a0'>diff</a>)</td></tr></table>
<div class='commit-subject'>lwtunnel: Fix oops on state free after encap module unload</div><div class='commit-msg'>When attempting to free lwtunnel state after the module for the encap
has been unloaded an oops occurs:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
IP: lwtstate_free+0x18/0x40
[..]
task: ffff88003e372380 task.stack: ffffc900001fc000
RIP: 0010:lwtstate_free+0x18/0x40
RSP: 0018:ffff88003fd83e88 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88002bbb3380 RCX: ffff88000c91a300
[..]
Call Trace:
 &lt;IRQ&gt;
 free_fib_info_rcu+0x195/0x1a0
 ? rt_fibinfo_free+0x50/0x50
 rcu_process_callbacks+0x2d3/0x850
 ? rcu_process_callbacks+0x296/0x850
 __do_softirq+0xe4/0x4cb
 irq_exit+0xb0/0xc0
 smp_apic_timer_interrupt+0x3d/0x50
 apic_timer_interrupt+0x93/0xa0
[..]
Code: e8 6e c6 fc ff 89 d8 5b 5d c3 bb de ff ff ff eb f4 66 90 66 66 66 66 90 55 48 89 e5 53 0f b7 07 48 89 fb 48 8b 04 c5 00 81 d5 81 &lt;48&gt; 8b 40 08 48 85 c0 74 13 ff d0 48 8d 7b 20 be 20 00 00 00 e8

The problem is after the module for the encap can be unloaded the
corresponding ops is removed and is thus NULL here.

Modules implementing lwtunnel ops should not be allowed to unload
while there is state alive using those ops, so grab the module
reference for the ops on creating lwtunnel state and of course release
the reference when freeing the state.

Fixes: 1104d9ba443a ("lwtunnel: Add destroy state operation")
Signed-off-by: Robert Shearman &lt;rshearma@brocade.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=85c814016ce3b371016c2c054a905fa2492f5a65'>Diffstat</a></div><table summary='diffstat' class='diffstat'>