linux/net
Eric Dumazet 8be2d38bb3 tcp: md5: reject TCP_MD5SIG or TCP_MD5SIG_EXT on established sockets
[ Upstream commit 7212303268 ]

syzbot/KMSAN reported an uninit-value in tcp_parse_options() [1]

I believe this was caused by a TCP_MD5SIG being set on live
flow.

This is highly unexpected, since TCP option space is limited.

For instance, presence of TCP MD5 option automatically disables
TCP TimeStamp option at SYN/SYNACK time, which we can not do
once flow has been established.

Really, adding/deleting an MD5 key only makes sense on sockets
in CLOSE or LISTEN state.

[1]
BUG: KMSAN: uninit-value in tcp_parse_options+0xd74/0x1a30 net/ipv4/tcp_input.c:3720
CPU: 1 PID: 6177 Comm: syzkaller192004 Not tainted 4.16.0+ #83
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
 tcp_parse_options+0xd74/0x1a30 net/ipv4/tcp_input.c:3720
 tcp_fast_parse_options net/ipv4/tcp_input.c:3858 [inline]
 tcp_validate_incoming+0x4f1/0x2790 net/ipv4/tcp_input.c:5184
 tcp_rcv_established+0xf60/0x2bb0 net/ipv4/tcp_input.c:5453
 tcp_v4_do_rcv+0x6cd/0xd90 net/ipv4/tcp_ipv4.c:1469
 sk_backlog_rcv include/net/sock.h:908 [inline]
 __release_sock+0x2d6/0x680 net/core/sock.c:2271
 release_sock+0x97/0x2a0 net/core/sock.c:2786
 tcp_sendmsg+0xd6/0x100 net/ipv4/tcp.c:1464
 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747
 SyS_sendto+0x8a/0xb0 net/socket.c:1715
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x448fe9
RSP: 002b:00007fd472c64d38 EFLAGS: 00000216 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00000000006e5a30 RCX: 0000000000448fe9
RDX: 000000000000029f RSI: 0000000020a88f88 RDI: 0000000000000004
RBP: 00000000006e5a34 R08: 0000000020e68000 R09: 0000000000000010
R10: 00000000200007fd R11: 0000000000000216 R12: 0000000000000000
R13: 00007fff074899ef R14: 00007fd472c659c0 R15: 0000000000000009

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188
 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314
 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc_node mm/slub.c:2737 [inline]
 __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:984 [inline]
 tcp_send_ack+0x18c/0x910 net/ipv4/tcp_output.c:3624
 __tcp_ack_snd_check net/ipv4/tcp_input.c:5040 [inline]
 tcp_ack_snd_check net/ipv4/tcp_input.c:5053 [inline]
 tcp_rcv_established+0x2103/0x2bb0 net/ipv4/tcp_input.c:5469
 tcp_v4_do_rcv+0x6cd/0xd90 net/ipv4/tcp_ipv4.c:1469
 sk_backlog_rcv include/net/sock.h:908 [inline]
 __release_sock+0x2d6/0x680 net/core/sock.c:2271
 release_sock+0x97/0x2a0 net/core/sock.c:2786
 tcp_sendmsg+0xd6/0x100 net/ipv4/tcp.c:1464
 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747
 SyS_sendto+0x8a/0xb0 net/socket.c:1715
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2

Fixes: cfb6eeb4c8 ("[TCP]: MD5 Signature Option (RFC2385) support.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-29 07:50:06 +02:00
..
6lowpan 6lowpan: put mcast compression in an own function 2015-10-21 00:49:25 +02:00
9p net/9p: Switch to wait_event_killable() 2017-11-30 08:37:25 +00:00
802
8021q vlan: also check phy_driver ts_info for vlan's real device 2018-04-13 19:50:25 +02:00
appletalk
atm
ax25 ax25: Fix segfault after sock connection timeout 2017-02-04 09:45:09 +01:00
batman-adv batman-adv: handle race condition for claims between gateways 2018-03-22 09:23:21 +01:00
bluetooth Bluetooth: Send HCI Set Event Mask Page 2 command only when needed 2018-04-13 19:50:21 +02:00
bridge netfilter: bridge: ebt_among: add more missing match size checks 2018-04-08 11:51:59 +02:00
caif net: caif: Fix a sleep-in-atomic bug in cfpkt_create_pfx 2017-07-05 14:37:14 +02:00
can can: af_can: canfd_rcv(): replace WARN_ONCE by pr_warn_once 2018-01-31 12:06:08 +01:00
ceph libceph: NULL deref on crush_decode() error path 2018-04-13 19:50:10 +02:00
core net: fix deadlock while clearing neighbor proxy table 2018-04-29 07:50:06 +02:00
dcb net/dcb: make dcbnl.c explicitly non-modular 2015-10-09 07:52:27 -07:00
dccp dccp: check sk for closed state in dccp_sendmsg() 2018-03-31 18:12:33 +02:00
decnet dn_getsockoptdecnet: move nf_{get/set}sockopt outside sock lock 2018-02-25 11:03:38 +01:00
dns_resolver KEYS: DNS: limit the length of option strings 2018-04-29 07:50:04 +02:00
dsa net: dsa: select NET_SWITCHDEV 2017-11-15 17:13:11 +01:00
ethernet net: introduce device min_header_len 2017-02-18 16:39:27 +01:00
hsr net/hsr: fix a warning message 2015-11-23 14:56:15 -05:00
ieee802154 net: ieee802154: fix net_device reference release too early 2018-04-13 19:50:10 +02:00
ipv4 tcp: md5: reject TCP_MD5SIG or TCP_MD5SIG_EXT on established sockets 2018-04-29 07:50:06 +02:00
ipv6 ipv6: the entire IPv6 header chain must fit the first fragment 2018-04-13 19:50:27 +02:00
ipx ipx: call ipxitf_put() in ioctl error path 2017-05-25 14:30:13 +02:00
irda irda: do not leak initialized list.dev to userspace 2017-08-30 10:19:21 +02:00
iucv net/iucv: Free memory obtained by kzalloc 2018-03-31 18:12:33 +02:00
key af_key: Fix slab-out-of-bounds in pfkey_compile_policy. 2018-04-13 19:50:01 +02:00
l2tp l2tp: check sockaddr length in pppol2tp_connect() 2018-04-29 07:50:04 +02:00
l3mdev net: Add netif_is_l3_slave 2015-10-07 04:27:43 -07:00
lapb
llc llc: fix NULL pointer deref for SOCK_ZAPPED 2018-04-29 07:50:06 +02:00
mac80211 mac80211: bail out from prep_connection() if a reconfig is ongoing 2018-04-13 19:50:01 +02:00
mac802154 mac802154: llsec: use kzfree 2015-10-21 00:49:24 +02:00
mpls mpls, nospec: Sanitize array index in mpls_label_ok() 2018-03-11 16:19:47 +01:00
netfilter netfilter: ctnetlink: fix incorrect nf_ct_put during hash resize 2018-04-13 19:50:10 +02:00
netlabel netlabel: add address family checks to netlbl_{sock,req}_delattr() 2016-08-20 18:09:22 +02:00
netlink netlink: make sure nladdr has correct size in netlink_connect() 2018-04-13 19:50:24 +02:00
netrom
nfc NFC: fix device-allocation error return 2017-11-30 08:37:23 +00:00
openvswitch openvswitch: Delete conntrack entry clashing with an expectation. 2018-03-24 10:58:43 +01:00
packet packet: fix bitfield update race 2018-04-29 07:50:05 +02:00
phonet phonet: properly unshare skbs in phonet_rcv() 2016-01-31 11:29:00 -08:00
rds rds; Reset rs->rs_bound_addr in rds_add_bound() failure path 2018-04-13 19:50:13 +02:00
rfkill rfkill: fix rfkill_fop_read wait_event usage 2016-03-03 15:07:26 -08:00
rose
rxrpc rxrpc: check return value of skb_to_sgvec always 2018-04-13 19:50:23 +02:00
sched net sched actions: fix dumping which requires several messages to user space 2018-04-13 19:50:27 +02:00
sctp sctp: do not check port in sctp_inet6_cmp_addr 2018-04-29 07:50:05 +02:00
sunrpc rpc_pipefs: fix double-dput() 2018-04-24 09:32:11 +02:00
switchdev switchdev: pass pointer to fib_info instead of copy 2016-06-24 10:18:16 -07:00
tipc tipc: add policy for TIPC_NLA_NET_ADDR 2018-04-29 07:50:06 +02:00
unix net/unix: don't show information about sockets from other namespaces 2017-11-18 11:11:06 +01:00
vmw_vsock vsock: use new wait API for vsock_stream_sendmsg() 2017-11-30 08:37:19 +00:00
wimax
wireless nl80211: Sanitize array index in parse_txq_params 2018-02-25 11:03:53 +01:00
x25 net: x25: fix one potential use-after-free issue 2018-04-13 19:50:07 +02:00
xfrm xfrm: fix state migration copy replay sequence numbers 2018-04-13 19:50:08 +02:00
compat.c audit: log 32-bit socketcalls 2017-10-08 10:14:18 +02:00
Kconfig Make DST_CACHE a silent config option 2018-02-25 11:03:37 +01:00
Makefile net: Introduce L3 Master device abstraction 2015-09-29 20:40:32 -07:00
socket.c bpf: introduce BPF_JIT_ALWAYS_ON config 2018-02-03 17:04:24 +01:00
sysctl_net.c net: Use ns_capable_noaudit() when determining net sysctl permissions 2016-09-15 08:27:50 +02:00