linux/net
Toshiaki Makita ae4745730c net: Fix untag for vlan packets without ethernet header
In some situation vlan packets do not have ethernet headers. One example
is packets from tun devices. Users can specify vlan protocol in tun_pi
field instead of IP protocol, and skb_vlan_untag() attempts to untag such
packets.

skb_vlan_untag() (more precisely, skb_reorder_vlan_header() called by it)
however did not expect packets without ethernet headers, so in such a case
size argument for memmove() underflowed and triggered crash.

====
BUG: unable to handle kernel paging request at ffff8801cccb8000
IP: __memmove+0x24/0x1a0 arch/x86/lib/memmove_64.S:43
PGD 9cee067 P4D 9cee067 PUD 1d9401063 PMD 1cccb7063 PTE 2810100028101
Oops: 000b [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 17663 Comm: syz-executor2 Not tainted 4.16.0-rc7+ #368
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__memmove+0x24/0x1a0 arch/x86/lib/memmove_64.S:43
RSP: 0018:ffff8801cc046e28 EFLAGS: 00010287
RAX: ffff8801ccc244c4 RBX: fffffffffffffffe RCX: fffffffffff6c4c2
RDX: fffffffffffffffe RSI: ffff8801cccb7ffc RDI: ffff8801cccb8000
RBP: ffff8801cc046e48 R08: ffff8801ccc244be R09: ffffed0039984899
R10: 0000000000000001 R11: ffffed0039984898 R12: ffff8801ccc244c4
R13: ffff8801ccc244c0 R14: ffff8801d96b7c06 R15: ffff8801d96b7b40
FS:  00007febd562d700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff8801cccb8000 CR3: 00000001ccb2f006 CR4: 00000000001606e0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 memmove include/linux/string.h:360 [inline]
 skb_reorder_vlan_header net/core/skbuff.c:5031 [inline]
 skb_vlan_untag+0x470/0xc40 net/core/skbuff.c:5061
 __netif_receive_skb_core+0x119c/0x3460 net/core/dev.c:4460
 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4627
 netif_receive_skb_internal+0x10b/0x670 net/core/dev.c:4701
 netif_receive_skb+0xae/0x390 net/core/dev.c:4725
 tun_rx_batched.isra.50+0x5ee/0x870 drivers/net/tun.c:1555
 tun_get_user+0x299e/0x3c20 drivers/net/tun.c:1962
 tun_chr_write_iter+0xb9/0x160 drivers/net/tun.c:1990
 call_write_iter include/linux/fs.h:1782 [inline]
 new_sync_write fs/read_write.c:469 [inline]
 __vfs_write+0x684/0x970 fs/read_write.c:482
 vfs_write+0x189/0x510 fs/read_write.c:544
 SYSC_write fs/read_write.c:589 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:581
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x454879
RSP: 002b:00007febd562cc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007febd562d6d4 RCX: 0000000000454879
RDX: 0000000000000157 RSI: 0000000020000180 RDI: 0000000000000014
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000006b0 R14: 00000000006fc120 R15: 0000000000000000
Code: 90 90 90 90 90 90 90 48 89 f8 48 83 fa 20 0f 82 03 01 00 00 48 39 fe 7d 0f 49 89 f0 49 01 d0 49 39 f8 0f 8f 9f 00 00 00 48 89 d1 <f3> a4 c3 48 81 fa a8 02 00 00 72 05 40 38 fe 74 3b 48 83 ea 20
RIP: __memmove+0x24/0x1a0 arch/x86/lib/memmove_64.S:43 RSP: ffff8801cc046e28
CR2: ffff8801cccb8000
====

We don't need to copy headers for packets which do not have preceding
headers of vlan headers, so skip memmove() in that case.

Fixes: 4bbb3e0e82 ("net: Fix vlan untag for bridge and vlan_dev with reorder_hdr off")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-30 12:36:27 -04:00
..
6lowpan
9p virtio: bugfixes 2018-02-15 14:29:27 -08:00
802 treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
8021q vlan: Fix out of order vlan headers with reorder header off 2018-03-16 10:03:47 -04:00
appletalk net: delete /proc THIS_MODULE references 2018-01-16 15:01:33 -05:00
atm vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
ax25 net: delete /proc THIS_MODULE references 2018-01-16 15:01:33 -05:00
batman-adv batman-adv: fix packet loss for broadcasted DHCP packets to a server 2018-03-24 10:25:49 +01:00
bluetooth Bluetooth: Fix missing encryption refresh on Security Request 2018-03-01 19:55:56 +01:00
bpf bpf: fix null pointer deref in bpf_prog_test_run_xdp 2018-02-01 07:43:56 -08:00
bridge netfilter: bridge: ebt_among: add more missing match size checks 2018-03-11 21:24:49 +01:00
caif vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
can can: migrate documentation to restructured text 2018-01-26 10:46:44 +01:00
ceph libceph, ceph: avoid memory leak when specifying same option several times 2018-02-26 16:19:30 +01:00
core net: Fix untag for vlan packets without ethernet header 2018-03-30 12:36:27 -04:00
dcb
dccp dccp: check sk for closed state in dccp_sendmsg() 2018-03-07 13:38:56 -05:00
decnet dn_getsockoptdecnet: move nf_{get/set}sockopt outside sock lock 2018-02-16 15:46:15 -05:00
dns_resolver afs: Support the AFS dynamic root 2018-02-06 14:43:37 +00:00
dsa net: dsa: Fix dsa_is_user_port() test inversion 2018-03-12 21:04:55 -04:00
ethernet
hsr
ieee802154 ieee802154: 6lowpan: fix possible NULL deref in lowpan_device_event() 2018-03-09 11:19:26 -05:00
ife
ipv4 ip_tunnel: Resolve ipsec merge conflict properly. 2018-03-29 11:42:14 -04:00
ipv6 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec 2018-03-29 10:12:47 -04:00
iucv net/iucv: Free memory obtained by kzalloc 2018-03-16 11:42:12 -04:00
kcm kcm: lock lower socket in kcm_attach 2018-03-16 11:12:16 -04:00
key af_key: Fix memory leak in key_notify_policy. 2018-01-10 09:45:11 +01:00
l2tp l2tp: fix races with ipv4-mapped ipv6 addresses 2018-03-12 15:11:09 -04:00
l3mdev
lapb treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts 2017-11-21 16:35:54 -08:00
llc llc: properly handle dev_queue_xmit() return value 2018-03-27 11:56:00 -04:00
mac80211 mac80211: add ieee80211_hw flag for QoS NDP support 2018-03-21 10:56:18 +01:00
mac802154
mpls net: rename skb_gso_validate_mtu -> skb_gso_validate_network_len 2018-03-04 17:49:17 -05:00
ncsi net/ncsi: Don't take any action on HNCDSC AEN 2017-12-18 14:50:11 -05:00
netfilter netfilter: nf_tables: do not hold reference on netdevice from preparation phase 2018-03-22 13:17:52 +01:00
netlabel net/netlabel: Add list_next_rcu() in rcu_dereference(). 2017-11-18 10:32:41 +09:00
netlink netlink: make sure nladdr has correct size in netlink_connect() 2018-03-25 21:14:51 -04:00
netrom net: delete /proc THIS_MODULE references 2018-01-16 15:01:33 -05:00
nfc NFC: llcp: Limit size of SDP URI 2018-02-16 15:16:05 -05:00
nsh
openvswitch openvswitch: meter: fix the incorrect calculation of max delta_t 2018-03-11 22:48:59 -04:00
packet vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
phonet vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
psample
qrtr qrtr: add MODULE_ALIAS macro to smd 2018-02-26 15:07:04 -05:00
rds rds: Incorrect reference counting in TCP socket creation 2018-03-02 09:40:27 -05:00
rfkill vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
rose net: delete /proc THIS_MODULE references 2018-01-16 15:01:33 -05:00
rxrpc rxrpc: Fix send in rxrpc_send_data_packet() 2018-02-22 15:37:47 -05:00
sched net sched actions: fix dumping which requires several messages to user space 2018-03-27 10:59:12 -04:00
sctp net: use skb_is_gso_sctp() instead of open-coding 2018-03-09 11:41:47 -05:00
smc net/smc: use announced length in sock_recvmsg() 2018-03-27 11:59:49 -04:00
strparser strparser: Fix sign of err codes 2018-03-27 11:00:18 -04:00
sunrpc vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
switchdev net: bridge: Add/del switchdev object on host join/leave 2017-11-10 13:41:40 +09:00
tipc tipc: correct initial value for group congestion flag 2018-02-27 11:46:03 -05:00
tls tls: Use correct sk->sk_prot for IPV6 2018-02-27 14:41:48 -05:00
unix net: af_unix: fix typo in UNIX_SKB_FRAGS_SZ comment 2018-02-13 12:21:45 -05:00
vmw_vsock vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
wimax
wireless cfg80211: add missing dependency to CFG80211 suboptions 2018-02-27 10:54:12 +01:00
x25 treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts 2017-11-21 16:35:54 -08:00
xfrm xfrm: Fix transport mode skb control buffer usage. 2018-03-23 07:56:04 +01:00
compat.c
Kconfig Staging/IIO patches for 4.16-rc1 2018-02-01 09:51:57 -08:00
Makefile ipx: move Novell IPX protocol support into staging 2017-11-28 13:55:00 +01:00
socket.c sock_diag: request _diag module only when the family or proto has been registered 2018-03-12 11:03:42 -04:00
sysctl_net.c