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

#include <stdio.h>
#include <stdint.h>
#include <endian.h>
#include <netinet/in.h>    /* for ntohs() */
#include <asm/byteorder.h>

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

struct tcphdr {
	uint16_t source;
	uint16_t dest;
	uint32_t seq;
	uint32_t ack_seq;
#if defined(__LITTLE_ENDIAN_BITFIELD)
	__extension__ uint16_t res1:4,
			       doff:4,
			       fin:1,
			       syn:1,
			       rst:1,
			       psh:1,
			       ack:1,
			       urg:1,
			       ece:1,
			       cwr:1;
#elif defined(__BIG_ENDIAN_BITFIELD)
	__extension__ uint16_t doff:4,
			       res1:4,
			       cwr:1,
			       ece:1,
			       urg:1,
			       ack:1,
			       psh:1,
			       rst:1,
			       syn:1,
			       fin:1;
#else
# error  "Adjust your <asm/byteorder.h> defines"
#endif
	uint16_t window;
	uint16_t check;
	uint16_t urg_ptr;
} __packed;

static void tcp(struct pkt_buff *pkt)
{
	struct tcphdr *tcp = (struct tcphdr *) pkt_pull(pkt, sizeof(*tcp));
	uint16_t src, dest;
	char *src_name, *dest_name;

	if (tcp == NULL)
		return;

	src = ntohs(tcp->source);
	dest = ntohs(tcp->dest);

	src_name = lookup_port_tcp(src);
	dest_name = lookup_port_tcp(dest);

	tprintf(" [ TCP ");
	tprintf("Port (%u", src);
	if (src_name)
		tprintf(" (%s%s%s)", colorize_start(bold), src_name,
			colorize_end());
	tprintf(" => %u", dest);
	if (dest_name)
		tprintf(" (%s%s%s)", colorize_start(bold), dest_name,
			colorize_end());
	tprintf("), ");
	tprintf("SN (0x%x), ", ntohl(tcp->seq));
	tprintf("AN (0x%x), ", ntohl(tcp->ack_seq));
	tprintf("DataOff (%u), ", tcp->doff);
	tprintf("Res (%u), ", tcp->res1);
	tprintf("Flags (");
	if (tcp->fin)
		tprintf("FIN ");
	if (tcp->syn)
		tprintf("SYN ");
	if (tcp->rst)
		tprintf("RST ");
	if (tcp->psh)
		tprintf("PSH ");
	if (tcp->ack)
		tprintf("ACK ");
	if (tcp->urg)
		tprintf("URG ");
	if (tcp->ece)
		tprintf("ECE ");
	if (tcp->cwr)
		tprintf("CWR ");
	tprintf("), ");
	tprintf("Window (%u), ", ntohs(tcp->window));
	tprintf("CSum (0x%.4x), ", ntohs(tcp->check));
	tprintf("UrgPtr (%u)", ntohs(tcp->urg_ptr));
	tprintf(" ]\n");
}

static void tcp_less(struct pkt_buff *pkt)
{
	struct tcphdr *tcp = (struct tcphdr *) pkt_pull(pkt, sizeof(*tcp));
	uint16_t src, dest;
	char *src_name, *dest_name;

	if (tcp == NULL)
		return;

	src = ntohs(tcp->source);
	dest = ntohs(tcp->dest);

	src_name = lookup_port_tcp(src);
	dest_name = lookup_port_tcp(dest);

	tprintf(" TCP %u", src);
	if(src_name)
		tprintf("(%s%s%s)", colorize_start(bold), src_name,
			colorize_end());
	tprintf("/%u", dest);
	if(dest_name)
		tprintf("(%s%s%s)", colorize_start(bold), dest_name,
			colorize_end());
	tprintf(" F%s",colorize_start(bold));
	if (tcp->fin)
		tprintf(" FIN");
	if (tcp->syn)
		tprintf(" SYN");
	if (tcp->rst)
		tprintf(" RST");
	if (tcp->psh)
		tprintf(" PSH");
	if (tcp->ack)
		tprintf(" ACK");
	if (tcp->urg)
		tprintf(" URG");
	if (tcp->ece)
		tprintf(" ECE");
	if (tcp->cwr)
		tprintf(" CWR");
	tprintf("%s Win %u S/A 0x%x/0x%x", colorize_end(),
		ntohs(tcp->window), ntohl(tcp->seq), ntohl(tcp->ack_seq));
}

struct protocol tcp_ops = {
	.key = 0x06,
	.print_full = tcp,
	.print_less = tcp_less,
};
ue='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>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>WANG Cong &lt;xiyou.wangcong@gmail.com&gt;</td><td class='right'>2017-02-08 10:02:13 -0800</td></tr>
<tr><th>committer</th><td>David S. Miller &lt;davem@davemloft.net&gt;</td><td class='right'>2017-02-08 13:12:22 -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=d7426c69a1942b2b9b709bf66b944ff09f561484'>d7426c69a1942b2b9b709bf66b944ff09f561484</a> (<a href='/cgit.cgi/linux/net-next.git/patch/?id=d7426c69a1942b2b9b709bf66b944ff09f561484'>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=d7426c69a1942b2b9b709bf66b944ff09f561484'>f32d0d878d78b43106a831b4b8f510c8a4b4d673</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=2bd137de531367fb573d90150d1872cb2a2095f7'>2bd137de531367fb573d90150d1872cb2a2095f7</a> (<a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=d7426c69a1942b2b9b709bf66b944ff09f561484&amp;id2=2bd137de531367fb573d90150d1872cb2a2095f7'>diff</a>)</td></tr></table>
<div class='commit-subject'>sit: fix a double free on error path</div><div class='commit-msg'>Dmitry reported a double free in sit_init_net():

  kernel BUG at mm/percpu.c:689!
  invalid opcode: 0000 [#1] SMP KASAN
  Dumping ftrace buffer:
     (ftrace buffer empty)
  Modules linked in:
  CPU: 0 PID: 15692 Comm: syz-executor1 Not tainted 4.10.0-rc6-next-20170206 #1
  Hardware name: Google Google Compute Engine/Google Compute Engine,
  BIOS Google 01/01/2011
  task: ffff8801c9cc27c0 task.stack: ffff88017d1d8000
  RIP: 0010:pcpu_free_area+0x68b/0x810 mm/percpu.c:689
  RSP: 0018:ffff88017d1df488 EFLAGS: 00010046
  RAX: 0000000000010000 RBX: 00000000000007c0 RCX: ffffc90002829000
  RDX: 0000000000010000 RSI: ffffffff81940efb RDI: ffff8801db841d94
  RBP: ffff88017d1df590 R08: dffffc0000000000 R09: 1ffffffff0bb3bdd
  R10: dffffc0000000000 R11: 00000000000135dd R12: ffff8801db841d80
  R13: 0000000000038e40 R14: 00000000000007c0 R15: 00000000000007c0
  FS:  00007f6ea608f700(0000) GS:ffff8801dbe00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 000000002000aff8 CR3: 00000001c8d44000 CR4: 00000000001426f0
  DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
  Call Trace:
   free_percpu+0x212/0x520 mm/percpu.c:1264
   ipip6_dev_free+0x43/0x60 net/ipv6/sit.c:1335
   sit_init_net+0x3cb/0xa10 net/ipv6/sit.c:1831
   ops_init+0x10a/0x530 net/core/net_namespace.c:115
   setup_net+0x2ed/0x690 net/core/net_namespace.c:291
   copy_net_ns+0x26c/0x530 net/core/net_namespace.c:396
   create_new_namespaces+0x409/0x860 kernel/nsproxy.c:106
   unshare_nsproxy_namespaces+0xae/0x1e0 kernel/nsproxy.c:205
   SYSC_unshare kernel/fork.c:2281 [inline]
   SyS_unshare+0x64e/0xfc0 kernel/fork.c:2231
   entry_SYSCALL_64_fastpath+0x1f/0xc2

This is because when tunnel-&gt;dst_cache init fails, we free dev-&gt;tstats
once in ipip6_tunnel_init() and twice in sit_init_net(). This looks
redundant but its ndo_uinit() does not seem enough to clean up everything
here. So avoid this by setting dev-&gt;tstats to NULL after the first free,
at least for -net.

Reported-by: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Signed-off-by: Cong Wang &lt;xiyou.wangcong@gmail.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=d7426c69a1942b2b9b709bf66b944ff09f561484'>Diffstat</a></div><table summary='diffstat' class='diffstat'><tr><td class='mode'>-rw-r--r--</td><td class='upd'><a href='/cgit.cgi/linux/net-next.git/diff/net/ipv6/sit.c?h=nds-private-remove&amp;id=d7426c69a1942b2b9b709bf66b944ff09f561484'>net/ipv6/sit.c</a></td><td class='right'>1</td><td class='graph'><table summary='file diffstat' width='1%'><tr><td class='add' style='width: 100.0%;'/><td class='rem' style='width: 0.0%;'/><td class='none' style='width: 0.0%;'/></tr></table></td></tr>
</table><div class='diffstat-summary'>1 files changed, 1 insertions, 0 deletions</div><table summary='diff' class='diff'><tr><td><div class='head'>diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c