linux/net/ipv4
Nikolay Aleksandrov eeaac3634e net: nexthop: don't allow empty NHA_GROUP
Currently the nexthop code will use an empty NHA_GROUP attribute, but it
requires at least 1 entry in order to function properly. Otherwise we
end up derefencing null or random pointers all over the place due to not
having any nh_grp_entry members allocated, nexthop code relies on having at
least the first member present. Empty NHA_GROUP doesn't make any sense so
just disallow it.
Also add a WARN_ON for any future users of nexthop_create_group().

 BUG: kernel NULL pointer dereference, address: 0000000000000080
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 0 P4D 0
 Oops: 0000 [#1] SMP
 CPU: 0 PID: 558 Comm: ip Not tainted 5.9.0-rc1+ #93
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-2.fc32 04/01/2014
 RIP: 0010:fib_check_nexthop+0x4a/0xaa
 Code: 0f 84 83 00 00 00 48 c7 02 80 03 f7 81 c3 40 80 fe fe 75 12 b8 ea ff ff ff 48 85 d2 74 6b 48 c7 02 40 03 f7 81 c3 48 8b 40 10 <48> 8b 80 80 00 00 00 eb 36 80 78 1a 00 74 12 b8 ea ff ff ff 48 85
 RSP: 0018:ffff88807983ba00 EFLAGS: 00010213
 RAX: 0000000000000000 RBX: ffff88807983bc00 RCX: 0000000000000000
 RDX: ffff88807983bc00 RSI: 0000000000000000 RDI: ffff88807bdd0a80
 RBP: ffff88807983baf8 R08: 0000000000000dc0 R09: 000000000000040a
 R10: 0000000000000000 R11: ffff88807bdd0ae8 R12: 0000000000000000
 R13: 0000000000000000 R14: ffff88807bea3100 R15: 0000000000000001
 FS:  00007f10db393700(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000080 CR3: 000000007bd0f004 CR4: 00000000003706f0
 Call Trace:
  fib_create_info+0x64d/0xaf7
  fib_table_insert+0xf6/0x581
  ? __vma_adjust+0x3b6/0x4d4
  inet_rtm_newroute+0x56/0x70
  rtnetlink_rcv_msg+0x1e3/0x20d
  ? rtnl_calcit.isra.0+0xb8/0xb8
  netlink_rcv_skb+0x5b/0xac
  netlink_unicast+0xfa/0x17b
  netlink_sendmsg+0x334/0x353
  sock_sendmsg_nosec+0xf/0x3f
  ____sys_sendmsg+0x1a0/0x1fc
  ? copy_msghdr_from_user+0x4c/0x61
  ___sys_sendmsg+0x63/0x84
  ? handle_mm_fault+0xa39/0x11b5
  ? sockfd_lookup_light+0x72/0x9a
  __sys_sendmsg+0x50/0x6e
  do_syscall_64+0x54/0xbe
  entry_SYSCALL_64_after_hwframe+0x44/0xa9
 RIP: 0033:0x7f10dacc0bb7
 Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb cd 66 0f 1f 44 00 00 8b 05 9a 4b 2b 00 85 c0 75 2e 48 63 ff 48 63 d2 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 8b 15 b1 f2 2a 00 f7 d8 64 89 02 48
 RSP: 002b:00007ffcbe628bf8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
 RAX: ffffffffffffffda RBX: 00007ffcbe628f80 RCX: 00007f10dacc0bb7
 RDX: 0000000000000000 RSI: 00007ffcbe628c60 RDI: 0000000000000003
 RBP: 000000005f41099c R08: 0000000000000001 R09: 0000000000000008
 R10: 00000000000005e9 R11: 0000000000000246 R12: 0000000000000000
 R13: 0000000000000000 R14: 00007ffcbe628d70 R15: 0000563a86c6e440
 Modules linked in:
 CR2: 0000000000000080

CC: David Ahern <dsahern@gmail.com>
Fixes: 430a049190 ("nexthop: Add support for nexthop groups")
Reported-by: syzbot+a61aa19b0c14c8770bd9@syzkaller.appspotmail.com
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-22 12:39:55 -07:00
..
bpfilter net: Revert "net: optimize the sockptr_t for unified kernel/user address spaces" 2020-08-10 12:06:44 -07:00
netfilter Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-08-05 20:13:21 -07:00
Kconfig net: ipv4: remove duplicate "the the" phrase in Kconfig text 2020-08-18 16:02:16 -07:00
Makefile udp_tunnel: add central NIC RX port offload infrastructure 2020-07-10 13:54:00 -07:00
af_inet.c net: remove compat_sock_common_{get,set}sockopt 2020-07-19 18:16:40 -07:00
ah4.c
arp.c
bpf_tcp_ca.c
cipso_ipv4.c net: ipv4: kerneldoc fixes 2020-07-13 17:20:39 -07:00
datagram.c
devinet.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-05-31 17:48:46 -07:00
esp4.c
esp4_offload.c net: Add MODULE_DESCRIPTION entries to network modules 2020-06-20 21:33:57 -07:00
fib_frontend.c ipv4: nexthop version of fib_info_nh_uses_dev 2020-05-26 16:06:07 -07:00
fib_lookup.h
fib_notifier.c
fib_rules.c fib: use indirect call wrappers in the most common fib_rules_ops 2020-07-28 17:42:31 -07:00
fib_semantics.c net: Fix the arp error in some cases 2020-06-18 20:21:51 -07:00
fib_trie.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-08-02 01:02:12 -07:00
fou.c net: Add MODULE_DESCRIPTION entries to network modules 2020-06-20 21:33:57 -07:00
gre_demux.c
gre_offload.c net: gre: recompute gre csum for sctp over gre tunnels 2020-08-03 15:29:44 -07:00
icmp.c icmp6: support rfc 4884 2020-07-24 17:12:41 -07:00
igmp.c ip*_mc_gsfget(): lift copyout of struct group_filter into callers 2020-05-20 20:31:27 -04:00
inet_connection_sock.c net: refactor bind_bucket fastreuse into helper 2020-08-11 15:49:08 -07:00
inet_diag.c inet_diag: support for wider protocol numbers 2020-07-09 12:38:41 -07:00
inet_fragment.c
inet_hashtables.c net: initialize fastreuse on inet_inherit_port 2020-08-11 15:49:08 -07:00
inet_timewait_sock.c
inetpeer.c
ip_forward.c
ip_fragment.c
ip_gre.c net: add a new ndo_tunnel_ioctl method 2020-05-19 15:45:11 -07:00
ip_input.c
ip_options.c net/ipv4: merge ip_options_get and ip_options_get_from_user 2020-07-24 15:41:54 -07:00
ip_output.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-07-11 00:46:00 -07:00
ip_sockglue.c icmp: prepare rfc 4884 for ipv6 2020-07-24 17:12:41 -07:00
ip_tunnel.c ip_tunnel: fix use-after-free in ip_tunnel_lookup() 2020-06-18 20:12:34 -07:00
ip_tunnel_core.c Revert "ipv4: tunnel: fix compilation on ARCH=um" 2020-08-12 13:26:37 -07:00
ip_vti.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2020-07-30 14:39:31 -07:00
ipcomp.c ipcomp: assign if_id to child tunnel from parent tunnel 2020-07-09 12:55:37 +02:00
ipconfig.c
ipip.c net: ipip: implement header_ops->parse_protocol for AF_PACKET 2020-06-30 12:29:39 -07:00
ipmr.c ipmr: Copy option to correct variable 2020-07-27 11:39:55 -07:00
ipmr_base.c
metrics.c
netfilter.c
netlink.c
nexthop.c net: nexthop: don't allow empty NHA_GROUP 2020-08-22 12:39:55 -07:00
ping.c ipv4: fill fl4_icmp_{type,code} in ping_v4_sendmsg 2020-07-07 15:26:37 -07:00
proc.c tcp: add SNMP counter for no. of duplicate segments reported by DSACK 2020-07-17 12:54:30 -07:00
protocol.c
raw.c net: pass a sockptr_t into ->setsockopt 2020-07-24 15:41:54 -07:00
raw_diag.c
route.c ipv4: route: Ignore output interface in FIB lookup for PMTU route 2020-08-04 13:01:45 -07:00
syncookies.c tcp: fix build fong CONFIG_MPTCP=n 2020-08-01 11:46:29 -07:00
sysctl_net_ipv4.c tcp: correct read of TFO keys on big endian systems 2020-08-10 12:12:35 -07:00
tcp.c tcp: correct read of TFO keys on big endian systems 2020-08-10 12:12:35 -07:00
tcp_bbr.c
tcp_bic.c
tcp_bpf.c bpf: tcp: Recv() should return 0 when the peer socket is closed 2020-06-12 15:10:12 -07:00
tcp_cdg.c
tcp_cong.c tcp: make sure listeners don't initialize congestion-control state 2020-07-09 13:07:45 -07:00
tcp_cubic.c tcp_cubic: fix spurious HYSTART_DELAY exit upon drop in min RTT 2020-06-25 16:08:47 -07:00
tcp_dctcp.c
tcp_dctcp.h
tcp_diag.c
tcp_fastopen.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-08-13 20:03:11 -07:00
tcp_highspeed.c Replace HTTP links with HTTPS ones: IPv* 2020-07-06 13:23:03 -07:00
tcp_htcp.c Replace HTTP links with HTTPS ones: IPv* 2020-07-06 13:23:03 -07:00
tcp_hybla.c
tcp_illinois.c
tcp_input.c tcp: apply a floor of 1 for RTT samples from TCP timestamps 2020-08-03 17:54:03 -07:00
tcp_ipv4.c bpf: Refactor to provide aux info to bpf_iter_init_seq_priv_t 2020-07-25 20:16:32 -07:00
tcp_lp.c
tcp_metrics.c
tcp_minisocks.c mptcp: add new sock flag to deal with join subflows 2020-05-15 12:30:13 -07:00
tcp_nv.c
tcp_offload.c
tcp_output.c tcp: rename request_sock cookie_ts bit to syncookie 2020-07-31 16:55:32 -07:00
tcp_rate.c
tcp_recovery.c
tcp_scalable.c
tcp_timer.c net: ipv4: kerneldoc fixes 2020-07-13 17:20:39 -07:00
tcp_ulp.c
tcp_vegas.c
tcp_vegas.h
tcp_veno.c Replace HTTP links with HTTPS ones: IPv* 2020-07-06 13:23:03 -07:00
tcp_westwood.c
tcp_yeah.c
tunnel4.c tunnel4: add cb_handler to struct xfrm_tunnel 2020-07-09 12:51:36 +02:00
udp.c udp, bpf: Ignore connections in reuseport group after BPF sk lookup 2020-07-31 02:00:48 +02:00
udp_bpf.c
udp_diag.c
udp_impl.h net: pass a sockptr_t into ->setsockopt 2020-07-24 15:41:54 -07:00
udp_offload.c
udp_tunnel_core.c udp_tunnel: add central NIC RX port offload infrastructure 2020-07-10 13:54:00 -07:00
udp_tunnel_nic.c udp_tunnel: add the ability to hard-code IANA VXLAN 2020-08-03 10:13:54 -07:00
udp_tunnel_stub.c udp_tunnel: add central NIC RX port offload infrastructure 2020-07-10 13:54:00 -07:00
udplite.c net/ipv4: remove compat_ip_{get,set}sockopt 2020-07-19 18:16:41 -07:00
xfrm4_input.c xfrm: state: remove extract_input indirection from xfrm_state_afinfo 2020-05-06 09:40:08 +02:00
xfrm4_output.c xfrm: fix unused variable warning if CONFIG_NETFILTER=n 2020-05-11 15:12:27 +02:00
xfrm4_policy.c
xfrm4_protocol.c
xfrm4_state.c xfrm: remove output_finish indirection from xfrm_state_afinfo 2020-05-06 09:40:08 +02:00
xfrm4_tunnel.c