linux/net/ipv6
Eric Dumazet 3a5f238f2b ip6_tunnel: fix possible NULL deref in ip6_tnl_xmit
Make sure to test that skb has a dst attached to it.

general protection fault, probably for non-canonical address 0xdffffc0000000011: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000088-0x000000000000008f]
CPU: 0 PID: 32650 Comm: syz-executor.4 Not tainted 5.17.0-rc2-next-20220204-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:ip6_tnl_xmit+0x2140/0x35f0 net/ipv6/ip6_tunnel.c:1127
Code: 4d 85 f6 0f 85 c5 04 00 00 e8 9c b0 66 f9 48 83 e3 fe 48 b8 00 00 00 00 00 fc ff df 48 8d bb 88 00 00 00 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 07 7f 05 e8 11 25 b2 f9 44 0f b6 b3 88 00 00
RSP: 0018:ffffc900141b7310 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc9000c77a000
RDX: 0000000000000011 RSI: ffffffff8811f854 RDI: 0000000000000088
RBP: ffffc900141b7480 R08: 0000000000000000 R09: 0000000000000008
R10: ffffffff8811f846 R11: 0000000000000008 R12: ffffc900141b7548
R13: ffff8880297c6000 R14: 0000000000000000 R15: ffff8880351c8dc0
FS:  00007f9827ba2700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31322000 CR3: 0000000033a70000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ipxip6_tnl_xmit net/ipv6/ip6_tunnel.c:1386 [inline]
 ip6_tnl_start_xmit+0x71e/0x1830 net/ipv6/ip6_tunnel.c:1435
 __netdev_start_xmit include/linux/netdevice.h:4683 [inline]
 netdev_start_xmit include/linux/netdevice.h:4697 [inline]
 xmit_one net/core/dev.c:3473 [inline]
 dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3489
 __dev_queue_xmit+0x2a24/0x3760 net/core/dev.c:4116
 packet_snd net/packet/af_packet.c:3057 [inline]
 packet_sendmsg+0x2265/0x5460 net/packet/af_packet.c:3084
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 sock_write_iter+0x289/0x3c0 net/socket.c:1061
 call_write_iter include/linux/fs.h:2075 [inline]
 do_iter_readv_writev+0x47a/0x750 fs/read_write.c:726
 do_iter_write+0x188/0x710 fs/read_write.c:852
 vfs_writev+0x1aa/0x630 fs/read_write.c:925
 do_writev+0x27f/0x300 fs/read_write.c:968
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f9828c2d059

Fixes: c1f55c5e04 ("ip6_tunnel: allow routing IPv4 traffic in NBMA mode")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Qing Deng <i@moy.cat>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-09 11:56:19 +00:00
..
ila net: ipv6: check return value of rhashtable_init 2021-09-28 12:59:24 +01:00
netfilter netfilter: Remove flowtable relics 2022-01-27 00:00:20 +01:00
addrconf_core.c ipv6: add net device refcount tracker to struct inet6_dev 2021-12-06 16:05:11 -08:00
addrconf.c ipv6/addrconf: switch to per netns inet6_addr_lst hash table 2022-02-08 20:41:32 -08:00
addrlabel.c
af_inet6.c net: bpf: Handle return value of BPF_CGROUP_RUN_PROG_INET{4,6}_POST_BIND() 2022-01-06 17:08:35 -08:00
ah6.c ipv6: ah6: use swap() to make code cleaner 2021-11-18 12:00:15 +00:00
anycast.c
calipso.c
datagram.c
esp6_offload.c net: move gro definitions to include/net/gro.h 2021-11-16 13:16:54 +00:00
esp6.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2022-01-06 11:54:20 +00:00
exthdrs_core.c
exthdrs_offload.c
exthdrs.c ipv6: partially inline ipv6_fixup_options 2022-01-27 19:46:11 -08:00
fib6_notifier.c
fib6_rules.c ipv6: change fib6_rules_net_exit() to batch mode 2022-02-08 20:41:34 -08:00
fou6.c
icmp.c ipv6: do not use per netns icmp sockets 2022-01-25 11:25:21 +00:00
inet6_connection_sock.c
inet6_hashtables.c bpf: Add ingress_ifindex to bpf_sk_lookup 2021-11-10 16:29:58 -08:00
ioam6_iptunnel.c ipv6: ioam: Insertion frequency in lwtunnel output 2022-02-04 20:24:45 -08:00
ioam6.c ipv6: ioam: Support for Queue depth data field 2022-01-02 12:15:13 +00:00
ip6_checksum.c
ip6_fib.c ipv6: annotate accesses to fn->fn_sernum 2022-01-20 20:18:37 -08:00
ip6_flowlabel.c
ip6_gre.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-01-09 17:00:17 -08:00
ip6_icmp.c
ip6_input.c ipv6: make mc_forwarding atomic 2022-02-05 15:20:34 +00:00
ip6_offload.c ipv6: gro: flush instead of assuming different flows on hop_limit mismatch 2022-01-25 13:05:11 +00:00
ip6_offload.h
ip6_output.c ipv6: optimise dst refcounting on cork init 2022-01-27 19:46:11 -08:00
ip6_tunnel.c ip6_tunnel: fix possible NULL deref in ip6_tnl_xmit 2022-02-09 11:56:19 +00:00
ip6_udp_tunnel.c
ip6_vti.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-12-30 12:12:12 -08:00
ip6mr.c ip6mr: introduce ip6mr_net_exit_batch() 2022-02-08 20:41:34 -08:00
ipcomp6.c xfrm: remove hdr_offset indirection 2021-06-11 14:48:50 +02:00
ipv6_sockglue.c net-ipv6: changes to ->tclass (via IPV6_TCLASS) should sk_dst_reset() 2021-11-24 18:57:23 -08:00
Kconfig ipv6: ioam: Add support for the ip6ip6 encapsulation 2021-10-04 12:53:35 +01:00
Makefile net: ipv6: use ipv6-y directly instead of ipv6-objs 2021-09-28 13:13:40 +01:00
mcast_snoop.c
mcast.c ipv6: change return type from int to void for mld_process_v2 2021-09-02 11:29:55 +01:00
mip6.c xfrm: ipv6: move mip6_rthdr_offset into xfrm core 2021-06-11 14:48:50 +02:00
ndisc.c net: ndisc: introduce ndisc_evict_nocarrier sysctl parameter 2021-11-01 19:57:14 -07:00
netfilter.c
output_core.c
ping.c net: bpf: Handle return value of BPF_CGROUP_RUN_PROG_INET{4,6}_POST_BIND() 2022-01-06 17:08:35 -08:00
proc.c
protocol.c
raw.c ipv6: raw: check passed optlen before reading 2021-12-29 12:32:56 -08:00
reassembly.c
route.c ipv6: annotate accesses to fn->fn_sernum 2022-01-20 20:18:37 -08:00
rpl_iptunnel.c
rpl.c
seg6_hmac.c net: ipv6: check return value of rhashtable_init 2021-09-28 12:59:24 +01:00
seg6_iptunnel.c seg6: fix the iif in the IPv6 socket control block 2021-12-09 07:55:42 -08:00
seg6_local.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-01-05 14:36:10 -08:00
seg6.c icmp: ICMPV6: Examine invoking packet for Segment Route Headers. 2022-01-04 12:17:35 +00:00
sit.c sit: allow encapsulated IPv6 traffic to be delivered locally 2022-01-12 13:56:07 -08:00
syncookies.c net: align static siphash keys 2021-11-16 19:07:54 -08:00
sysctl_net_ipv6.c ipv6: ioam: Data plane support for Pre-allocated Trace 2021-07-21 08:14:33 -07:00
tcp_ipv6.c tcp: allocate tcp_death_row outside of struct netns_ipv4 2022-01-26 19:00:31 -08:00
tcpv6_offload.c net: move gro definitions to include/net/gro.h 2021-11-16 13:16:54 +00:00
tunnel6.c
udp_impl.h
udp_offload.c gro: remove rcu_read_lock/rcu_read_unlock from gro_receive handlers 2021-11-24 17:21:42 -08:00
udp.c ipv6: optimise dst refcounting on cork init 2022-01-27 19:46:11 -08:00
udplite.c
xfrm6_input.c
xfrm6_output.c net: ipv6: fix return value of ip6_skb_dst_mtu 2021-07-02 11:57:01 -07:00
xfrm6_policy.c xfrm: use net device refcount tracker helpers 2021-12-09 11:51:45 -08:00
xfrm6_protocol.c
xfrm6_state.c
xfrm6_tunnel.c xfrm: remove description from xfrm_type struct 2021-06-09 09:38:52 +02:00