WSL2-Linux-Kernel/net/ipv6
Eric Dumazet 8ce48623f0 ipv6: tcp: restore IP6CB for pktoptions skbs
Baozeng Ding reported following KASAN splat :

BUG: KASAN: use-after-free in ip6_datagram_recv_specific_ctl+0x13f1/0x15c0 at addr ffff880029c84ec8
Read of size 1 by task poc/25548
Call Trace:
 [<ffffffff82cf43c9>] dump_stack+0x12e/0x185 /lib/dump_stack.c:15
 [<     inline     >] print_address_description /mm/kasan/report.c:204
 [<ffffffff817ced3b>] kasan_report_error+0x48b/0x4b0 /mm/kasan/report.c:283
 [<     inline     >] kasan_report /mm/kasan/report.c:303
 [<ffffffff817ced9e>] __asan_report_load1_noabort+0x3e/0x40 /mm/kasan/report.c:321
 [<ffffffff85c71da1>] ip6_datagram_recv_specific_ctl+0x13f1/0x15c0 /net/ipv6/datagram.c:687
 [<ffffffff85c734c3>] ip6_datagram_recv_ctl+0x33/0x40
 [<ffffffff85c0b07c>] do_ipv6_getsockopt.isra.4+0xaec/0x2150
 [<ffffffff85c0c7f6>] ipv6_getsockopt+0x116/0x230
 [<ffffffff859b5a12>] tcp_getsockopt+0x82/0xd0 /net/ipv4/tcp.c:3035
 [<ffffffff855fb385>] sock_common_getsockopt+0x95/0xd0 /net/core/sock.c:2647
 [<     inline     >] SYSC_getsockopt /net/socket.c:1776
 [<ffffffff855f8ba2>] SyS_getsockopt+0x142/0x230 /net/socket.c:1758
 [<ffffffff8685cdc5>] entry_SYSCALL_64_fastpath+0x23/0xc6
Memory state around the buggy address:
 ffff880029c84d80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff880029c84e00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> ffff880029c84e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff880029c84f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff880029c84f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff

He also provided a syzkaller reproducer.

Issue is that ip6_datagram_recv_specific_ctl() expects to find IP6CB
data that was moved at a different place in tcp_v6_rcv()

This patch moves tcp_v6_restore_cb() up and calls it from
tcp_v6_do_rcv() when np->pktoptions is set.

Fixes: 971f10eca1 ("tcp: better TCP_SKB_CB layout to reduce cache line misses")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Baozeng Ding <sploving1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-13 11:07:34 -04:00
..
ila ila: make nla_policy const 2016-09-01 14:09:01 -07:00
netfilter Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2016-09-25 23:34:19 +02:00
Kconfig fou: fix IPv6 Kconfig options 2016-05-31 14:07:49 -07:00
Makefile Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/selinux into next 2016-07-07 10:15:34 +10:00
addrconf.c ipv6 addrconf: disallow rtr_solicits < -1 2016-10-07 23:43:56 -04:00
addrconf_core.c
addrlabel.c
af_inet6.c tcp: Set read_sock and peek_len proto_ops 2016-08-28 23:32:41 -04:00
ah6.c
anycast.c
calipso.c calipso: fix resource leak on calipso_genopt failure 2016-08-13 14:56:17 -07:00
datagram.c
esp6.c
exthdrs.c Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/selinux into next 2016-07-07 10:15:34 +10:00
exthdrs_core.c ipv6: constify the skb pointer of ipv6_find_tlv(). 2016-06-27 15:06:15 -04:00
exthdrs_offload.c
fib6_rules.c net: flow: Add l3mdev flow update 2016-09-10 23:12:51 -07:00
fou6.c fou: add Kconfig options for IPv6 support 2016-05-29 22:24:21 -07:00
icmp.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-06-30 05:03:36 -04:00
inet6_connection_sock.c
inet6_hashtables.c
ip6_checksum.c ipv6: fix checksum annotation in udp6_csum_init 2016-06-14 15:26:42 -04:00
ip6_fib.c ipv6: report NLM_F_CREATE and NLM_F_EXCL flags in RTM_NEWROUTE events 2016-09-09 16:50:23 -07:00
ip6_flowlabel.c
ip6_gre.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-10-02 22:20:41 -04:00
ip6_icmp.c ipv6: icmp: add a force_saddr param to icmp6_send() 2016-06-18 22:11:38 -07:00
ip6_input.c net: vrf: ipv6 support for local traffic to local addresses 2016-06-08 00:25:38 -07:00
ip6_offload.c gso: Support partial splitting at the frag_list pointer 2016-09-19 20:59:34 -04:00
ip6_offload.h
ip6_output.c net: ipv6: Remove l3mdev_get_saddr6 2016-09-10 23:12:53 -07:00
ip6_tunnel.c ip6_tunnel: add collect_md mode to IPv6 tunnels 2016-09-17 10:13:07 -04:00
ip6_udp_tunnel.c
ip6_vti.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-09-23 06:46:57 -04:00
ip6mr.c ipmr, ip6mr: fix scheduling while atomic and a deadlock with ipmr_get_route 2016-09-25 23:41:39 -04:00
ipcomp6.c
ipv6_sockglue.c Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/selinux into next 2016-07-07 10:15:34 +10:00
mcast.c net/multicast: should not send source list records when have filter mode change 2016-08-08 16:04:39 -07:00
mcast_snoop.c
mip6.c
ndisc.c net: l3mdev: remove redundant calls 2016-09-10 23:12:52 -07:00
netfilter.c
output_core.c net: l3mdev: Add hook to output path 2016-09-10 23:12:52 -07:00
ping.c ipv6: release dst in ping_v6_sendmsg 2016-09-06 12:54:17 -07:00
proc.c proc: Reduce cache miss in snmp6_seq_show 2016-09-30 01:50:44 -04:00
protocol.c
raw.c net: l3mdev: Add hook to output path 2016-09-10 23:12:52 -07:00
reassembly.c
route.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-10-02 22:20:41 -04:00
sit.c sit: make function ipip6_valid_ip_proto() static 2016-08-12 21:52:18 -07:00
syncookies.c
sysctl_net_ipv6.c calipso: Add a label cache. 2016-06-27 15:06:17 -04:00
tcp_ipv6.c ipv6: tcp: restore IP6CB for pktoptions skbs 2016-10-13 11:07:34 -04:00
tcpv6_offload.c
tunnel6.c
udp.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-08-30 00:54:02 -04:00
udp_impl.h ipv6: udp: remove udp_v6_clear_sk() 2016-08-23 23:23:50 -07:00
udp_offload.c
udplite.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-08-30 00:54:02 -04:00
xfrm6_input.c vti6: fix input path 2016-09-21 10:09:14 +02:00
xfrm6_mode_beet.c
xfrm6_mode_ro.c
xfrm6_mode_transport.c
xfrm6_mode_tunnel.c
xfrm6_output.c
xfrm6_policy.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-09-12 15:52:44 -07:00
xfrm6_protocol.c
xfrm6_state.c
xfrm6_tunnel.c vti6: fix input path 2016-09-21 10:09:14 +02:00