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
..
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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
addrconf_core.c
addrconf.c	ipv6 addrconf: disallow rtr_solicits < -1	2016-10-07 23:43:56 -04:00
addrlabel.c
af_inet6.c
ah6.c
anycast.c
calipso.c
datagram.c
esp6.c
exthdrs_core.c
exthdrs_offload.c
exthdrs.c
fib6_rules.c
fou6.c
icmp.c
inet6_connection_sock.c
inet6_hashtables.c
ip6_checksum.c
ip6_fib.c
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
ip6_input.c
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
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
Kconfig
Makefile
mcast_snoop.c
mcast.c
mip6.c
ndisc.c
netfilter.c
output_core.c
ping.c
proc.c	proc: Reduce cache miss in snmp6_seq_show	2016-09-30 01:50:44 -04:00
protocol.c
raw.c
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
syncookies.c
sysctl_net_ipv6.c
tcp_ipv6.c	ipv6: tcp: restore IP6CB for pktoptions skbs	2016-10-13 11:07:34 -04:00
tcpv6_offload.c
tunnel6.c
udp_impl.h
udp_offload.c
udp.c
udplite.c
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