alistair23-linux/net/ipv6
Hannes Frederic Sowa 75a493e60a ipv6: ip6_append_data_mtu did not care about pmtudisc and frag_size
If the socket had an IPV6_MTU value set, ip6_append_data_mtu lost track
of this when appending the second frame on a corked socket. This results
in the following splat:

[37598.993962] ------------[ cut here ]------------
[37598.994008] kernel BUG at net/core/skbuff.c:2064!
[37598.994008] invalid opcode: 0000 [#1] SMP
[37598.994008] Modules linked in: tcp_lp uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_core videodev media vfat fat usb_storage fuse ebtable_nat xt_CHECKSUM bridge stp llc ipt_MASQUERADE nf_conntrack_netbios_ns nf_conntrack_broadcast ip6table_mangle ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 iptable_nat
+nf_nat_ipv4 nf_nat iptable_mangle nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ebtable_filter ebtables ip6table_filter ip6_tables be2iscsi iscsi_boot_sysfs bnx2i cnic uio cxgb4i cxgb4 cxgb3i cxgb3 mdio libcxgbi ib_iser rdma_cm ib_addr iw_cm ib_cm ib_sa ib_mad ib_core iscsi_tcp libiscsi_tcp libiscsi
+scsi_transport_iscsi rfcomm bnep iTCO_wdt iTCO_vendor_support snd_hda_codec_conexant arc4 iwldvm mac80211 snd_hda_intel acpi_cpufreq mperf coretemp snd_hda_codec microcode cdc_wdm cdc_acm
[37598.994008]  snd_hwdep cdc_ether snd_seq snd_seq_device usbnet mii joydev btusb snd_pcm bluetooth i2c_i801 e1000e lpc_ich mfd_core ptp iwlwifi pps_core snd_page_alloc mei cfg80211 snd_timer thinkpad_acpi snd tpm_tis soundcore rfkill tpm tpm_bios vhost_net tun macvtap macvlan kvm_intel kvm uinput binfmt_misc
+dm_crypt i915 i2c_algo_bit drm_kms_helper drm i2c_core wmi video
[37598.994008] CPU 0
[37598.994008] Pid: 27320, comm: t2 Not tainted 3.9.6-200.fc18.x86_64 #1 LENOVO 27744PG/27744PG
[37598.994008] RIP: 0010:[<ffffffff815443a5>]  [<ffffffff815443a5>] skb_copy_and_csum_bits+0x325/0x330
[37598.994008] RSP: 0018:ffff88003670da18  EFLAGS: 00010202
[37598.994008] RAX: ffff88018105c018 RBX: 0000000000000004 RCX: 00000000000006c0
[37598.994008] RDX: ffff88018105a6c0 RSI: ffff88018105a000 RDI: ffff8801e1b0aa00
[37598.994008] RBP: ffff88003670da78 R08: 0000000000000000 R09: ffff88018105c040
[37598.994008] R10: ffff8801e1b0aa00 R11: 0000000000000000 R12: 000000000000fff8
[37598.994008] R13: 00000000000004fc R14: 00000000ffff0504 R15: 0000000000000000
[37598.994008] FS:  00007f28eea59740(0000) GS:ffff88023bc00000(0000) knlGS:0000000000000000
[37598.994008] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[37598.994008] CR2: 0000003d935789e0 CR3: 00000000365cb000 CR4: 00000000000407f0
[37598.994008] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[37598.994008] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[37598.994008] Process t2 (pid: 27320, threadinfo ffff88003670c000, task ffff88022c162ee0)
[37598.994008] Stack:
[37598.994008]  ffff88022e098a00 ffff88020f973fc0 0000000000000008 00000000000004c8
[37598.994008]  ffff88020f973fc0 00000000000004c4 ffff88003670da78 ffff8801e1b0a200
[37598.994008]  0000000000000018 00000000000004c8 ffff88020f973fc0 00000000000004c4
[37598.994008] Call Trace:
[37598.994008]  [<ffffffff815fc21f>] ip6_append_data+0xccf/0xfe0
[37598.994008]  [<ffffffff8158d9f0>] ? ip_copy_metadata+0x1a0/0x1a0
[37598.994008]  [<ffffffff81661f66>] ? _raw_spin_lock_bh+0x16/0x40
[37598.994008]  [<ffffffff8161548d>] udpv6_sendmsg+0x1ed/0xc10
[37598.994008]  [<ffffffff812a2845>] ? sock_has_perm+0x75/0x90
[37598.994008]  [<ffffffff815c3693>] inet_sendmsg+0x63/0xb0
[37598.994008]  [<ffffffff812a2973>] ? selinux_socket_sendmsg+0x23/0x30
[37598.994008]  [<ffffffff8153a450>] sock_sendmsg+0xb0/0xe0
[37598.994008]  [<ffffffff810135d1>] ? __switch_to+0x181/0x4a0
[37598.994008]  [<ffffffff8153d97d>] sys_sendto+0x12d/0x180
[37598.994008]  [<ffffffff810dfb64>] ? __audit_syscall_entry+0x94/0xf0
[37598.994008]  [<ffffffff81020ed1>] ? syscall_trace_enter+0x231/0x240
[37598.994008]  [<ffffffff8166a7e7>] tracesys+0xdd/0xe2
[37598.994008] Code: fe 07 00 00 48 c7 c7 04 28 a6 81 89 45 a0 4c 89 4d b8 44 89 5d a8 e8 1b ac b1 ff 44 8b 5d a8 4c 8b 4d b8 8b 45 a0 e9 cf fe ff ff <0f> 0b 66 0f 1f 84 00 00 00 00 00 66 66 66 66 90 55 48 89 e5 48
[37598.994008] RIP  [<ffffffff815443a5>] skb_copy_and_csum_bits+0x325/0x330
[37598.994008]  RSP <ffff88003670da18>
[37599.007323] ---[ end trace d69f6a17f8ac8eee ]---

While there, also check if path mtu discovery is activated for this
socket. The logic was adapted from ip6_append_data when first writing
on the corked socket.

This bug was introduced with commit
0c1833797a ("ipv6: fix incorrect ipsec
fragment").

v2:
a) Replace IPV6_PMTU_DISC_DO with IPV6_PMTUDISC_PROBE.
b) Don't pass ipv6_pinfo to ip6_append_data_mtu (suggestion by Gao
   feng, thanks!).
c) Change mtu to unsigned int, else we get a warning about
   non-matching types because of the min()-macro type-check.

Acked-by: Gao feng <gaofeng@cn.fujitsu.com>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-02 12:44:18 -07:00
..
netfilter net: always pass struct netdev_notifier_info to netdevice notifiers 2013-05-28 21:58:54 -07:00
addrconf.c ipv6,mcast: always hold idev->lock before mca_lock 2013-07-01 23:39:21 -07:00
addrconf_core.c ipv6: add include file to suppress sparse warnings 2013-06-25 02:44:05 -07:00
addrlabel.c rtnetlink: Remove passing of attributes into rtnl_doit functions 2013-03-22 10:31:16 -04:00
af_inet6.c net: ipv6: Add IPv6 support to the ping socket. 2013-05-25 21:07:49 -07:00
ah6.c
anycast.c
datagram.c net: ipv6: Unify {raw,udp}6_sock_seq_show. 2013-06-04 12:56:14 -07:00
esp6.c
exthdrs.c
exthdrs_core.c ipv6: Correct comparisons and calculations using skb->tail and skb-transport_header 2013-05-28 23:49:07 -07:00
exthdrs_offload.c
fib6_rules.c
icmp.c net: Convert uses of typedef ctl_table to struct ctl_table 2013-06-13 02:36:09 -07:00
inet6_connection_sock.c ipv6: use newly introduced __ipv6_addr_needs_scope_id and ipv6_iface_scope_id 2013-03-08 12:29:22 -05:00
inet6_hashtables.c
ip6_checksum.c
ip6_fib.c
ip6_flowlabel.c ipv6 flowlabel: add __rcu annotations 2013-03-07 16:33:10 -05:00
ip6_gre.c ipv6,gre: do not leak info to user-space 2013-05-11 17:40:14 -07:00
ip6_icmp.c ipv6: Kill ipv6 dependency of icmpv6_send(). 2013-04-29 13:54:36 -04:00
ip6_input.c ipv6: don't accept node local multicast traffic from the wire 2013-03-29 14:57:33 -04:00
ip6_offload.c MPLS: Add limited GSO support 2013-05-27 22:50:59 -07:00
ip6_offload.h
ip6_output.c ipv6: ip6_append_data_mtu did not care about pmtudisc and frag_size 2013-07-02 12:44:18 -07:00
ip6_tunnel.c GRE: Refactor GRE tunneling code. 2013-03-26 12:27:18 -04:00
ip6mr.c net: pass info struct via netdevice notifier 2013-05-28 13:11:01 -07:00
ipcomp6.c
ipv6_sockglue.c
Kconfig Tunneling: use IP Tunnel stats APIs. 2013-03-26 12:27:19 -04:00
Makefile net: ipv6: Add IPv6 support to the ping socket. 2013-05-25 21:07:49 -07:00
mcast.c ipv6,mcast: always hold idev->lock before mca_lock 2013-07-01 23:39:21 -07:00
mip6.c ipv6: Correct comparisons and calculations using skb->tail and skb-transport_header 2013-05-28 23:49:07 -07:00
ndisc.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-06-19 16:49:39 -07:00
netfilter.c netfilter: add nf_ipv6_ops hook to fix xt_addrtype with IPv6 2013-05-23 11:58:55 +02:00
output_core.c ipv6: Correct comparisons and calculations using skb->tail and skb-transport_header 2013-05-28 23:49:07 -07:00
ping.c net: ping_check_bind_addr() etc. can be static 2013-06-13 01:36:41 -07:00
proc.c snmp6: remove IPSTATS_MIB_CSUMERRORS 2013-05-31 16:26:49 -07:00
protocol.c
raw.c net: ipv6: Unify {raw,udp}6_sock_seq_show. 2013-06-04 12:56:14 -07:00
reassembly.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-04-22 20:32:51 -04:00
route.c ipv6: fix ecmp lookup when oif is specified 2013-07-01 13:27:38 -07:00
sit.c ipv6: only apply anti-spoofing checks to not-pointopoint tunnels 2013-07-01 13:26:18 -07:00
syncookies.c tcp: Remove TCPCT 2013-03-17 14:35:13 -04:00
sysctl_net_ipv6.c net: Convert uses of typedef ctl_table to struct ctl_table 2013-06-13 02:36:09 -07:00
tcp_ipv6.c tcp: add low latency socket poll support. 2013-06-10 21:22:36 -07:00
tcpv6_offload.c
tunnel6.c
udp.c ipv6: call udp_push_pending_frames when uncorking a socket with AF_INET pending data 2013-07-02 12:44:18 -07:00
udp_impl.h ipv6: do not clear pinet6 field 2013-05-11 16:26:38 -07:00
udp_offload.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-06-05 16:37:30 -07:00
udplite.c ipv6: do not clear pinet6 field 2013-05-11 16:26:38 -07:00
xfrm6_input.c
xfrm6_mode_beet.c
xfrm6_mode_ro.c
xfrm6_mode_transport.c
xfrm6_mode_tunnel.c xfrm: allow to avoid copying DSCP during encapsulation 2013-03-06 07:02:45 +01:00
xfrm6_output.c
xfrm6_policy.c xfrm6: release dev before returning error 2013-05-11 17:40:15 -07:00
xfrm6_state.c
xfrm6_tunnel.c