WSL2-Linux-Kernel/net
Willem de Bruijn 2efd4fca70 ip: in cmsg IP(V6)_ORIGDSTADDR call pskb_may_pull
Syzbot reported a read beyond the end of the skb head when returning
IPV6_ORIGDSTADDR:

  BUG: KMSAN: kernel-infoleak in put_cmsg+0x5ef/0x860 net/core/scm.c:242
  CPU: 0 PID: 4501 Comm: syz-executor128 Not tainted 4.17.0+ #9
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
  Google 01/01/2011
  Call Trace:
    __dump_stack lib/dump_stack.c:77 [inline]
    dump_stack+0x185/0x1d0 lib/dump_stack.c:113
    kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:1125
    kmsan_internal_check_memory+0x138/0x1f0 mm/kmsan/kmsan.c:1219
    kmsan_copy_to_user+0x7a/0x160 mm/kmsan/kmsan.c:1261
    copy_to_user include/linux/uaccess.h:184 [inline]
    put_cmsg+0x5ef/0x860 net/core/scm.c:242
    ip6_datagram_recv_specific_ctl+0x1cf3/0x1eb0 net/ipv6/datagram.c:719
    ip6_datagram_recv_ctl+0x41c/0x450 net/ipv6/datagram.c:733
    rawv6_recvmsg+0x10fb/0x1460 net/ipv6/raw.c:521
    [..]

This logic and its ipv4 counterpart read the destination port from
the packet at skb_transport_offset(skb) + 4.

With MSG_MORE and a local SOCK_RAW sender, syzbot was able to cook a
packet that stores headers exactly up to skb_transport_offset(skb) in
the head and the remainder in a frag.

Call pskb_may_pull before accessing the pointer to ensure that it lies
in skb head.

Link: http://lkml.kernel.org/r/CAF=yD-LEJwZj5a1-bAAj2Oy_hKmGygV6rsJ_WOrAYnv-fnayiQ@mail.gmail.com
Reported-by: syzbot+9adb4b567003cac781f0@syzkaller.appspotmail.com
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 16:35:58 -07:00
..
6lowpan License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
9p net/9p/client.c: put refcount of trans_mod in error case in parse_opts() 2018-07-14 11:11:09 -07:00
802 treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
8021q net: fix use-after-free in GRO with ESP 2018-07-02 20:34:04 +09:00
appletalk Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
atm Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
ax25 Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
batman-adv batman-adv: Fix multicast TT issues with bogus ROAM flags 2018-06-23 10:29:33 +02:00
bluetooth Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
bpf bpf: fix panic due to oob in bpf_prog_test_run_skb 2018-07-11 16:10:57 -07:00
bpfilter bpfilter: include bpfilter_umh in assembly instead of using objcopy 2018-06-28 21:39:16 +09:00
bridge Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-06-16 07:39:34 +09:00
caif net: caif: Add a missing rcu_read_unlock() in caif_flow_cb 2018-07-21 16:14:39 -07:00
can Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
ceph The main piece is a set of libceph changes that revamps how OSD 2018-06-15 07:24:58 +09:00
core sock: fix sg page frag coalescing in sk_alloc_sg 2018-07-23 21:28:45 -07:00
dcb treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
dccp Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
decnet Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
dns_resolver KEYS: DNS: fix parsing multiple options 2018-07-16 11:22:14 -07:00
dsa net: dsa: add error handling for pskb_trim_rcsum 2018-06-11 14:19:38 -07:00
ethernet net: core: rework basic flow dissection helper 2018-05-08 00:02:36 -04:00
hsr net: hsr: Convert timers to use timer_setup() 2017-10-25 13:00:27 +09:00
ieee802154 ieee802154: 6lowpan: set IFLA_LINK 2018-07-05 11:13:17 +02:00
ife net: sched: ife: check on metadata length 2018-04-22 21:12:00 -04:00
ipv4 ip: in cmsg IP(V6)_ORIGDSTADDR call pskb_may_pull 2018-07-24 16:35:58 -07:00
ipv6 ip: in cmsg IP(V6)_ORIGDSTADDR call pskb_may_pull 2018-07-24 16:35:58 -07:00
iucv Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
kcm Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
key Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
l2tp Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
l3mdev
lapb treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts 2017-11-21 16:35:54 -08:00
llc Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
mac80211 nl80211/mac80211: allow non-linear skb in rx_control_port 2018-07-06 14:34:42 +02:00
mac802154 net/mac802154: disambiguate mac80215 vs mac802154 trace events 2018-03-28 22:55:18 +02:00
mpls net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
ncsi net/ncsi: Use netdev_dbg for debug messages 2018-06-20 07:26:58 +09:00
netfilter netfilter: nf_tables: move dumper state allocation into ->start 2018-07-24 00:36:33 +02:00
netlabel audit: use inline function to get audit context 2018-05-14 17:24:18 -04:00
netlink Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
netrom Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
nfc net/nfc: Avoid stalls when nfc_alloc_send_skb() returned NULL. 2018-07-18 10:51:45 -07:00
nsh nsh: set mac len based on inner packet 2018-07-12 16:55:29 -07:00
openvswitch treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
packet packet: reset network header if packet shorter than ll reserved space 2018-07-12 16:55:59 -07:00
phonet Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
psample MAINTAINERS: Update Yotam's E-mail 2017-11-01 12:19:03 +09:00
qrtr net: qrtr: Reset the node and port ID of broadcast messages 2018-07-05 20:20:03 +09:00
rds rds: clean up loopback rds_connections on netns deletion 2018-06-27 10:11:03 +09:00
rfkill rfkill: Create rfkill-none LED trigger 2018-05-23 11:26:45 +02:00
rose Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
rxrpc Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
sched net: sched: Using NULL instead of plain integer 2018-07-18 13:44:07 -07:00
sctp sctp: fix the issue that pathmtu may be set lower than MINSEGMENT 2018-07-04 21:36:34 +09:00
smc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-07-18 19:32:54 -07:00
strparser strparser: Remove early eaten to fix full tcp receive buffer stall 2018-06-28 21:37:26 +09:00
sunrpc NFS client bugfixes for Linux 4.18 2018-06-22 06:21:34 +09:00
switchdev net: bridge: Add/del switchdev object on host join/leave 2017-11-10 13:41:40 +09:00
tipc tipc: make function tipc_net_finalize() thread safe 2018-07-07 19:49:02 +09:00
tls tls: check RCV_SHUTDOWN in tls_wait_data 2018-07-20 14:38:14 -07:00
unix Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
vmw_vsock Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
wimax License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
wireless cfg80211: never ignore user regulatory hint 2018-07-24 09:11:31 +02:00
x25 Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
xdp xsk: do not return EMSGSIZE in copy mode for packets larger than MTU 2018-07-13 15:34:31 +02:00
xfrm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
Kconfig net: Introduce generic failover module 2018-05-28 22:59:54 -04:00
Makefile bpfilter: check compiler capability in Kconfig 2018-06-28 13:36:39 +09:00
compat.c net: support compat 64-bit time in {s,g}etsockopt 2018-04-27 19:46:06 -04:00
socket.c net: handle NULL ->poll gracefully 2018-06-29 06:51:51 -07:00
sysctl_net.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00