linux/net/core
Ido Schimmel abd46fca02 rtnetlink: Disallow FDB configuration for non-Ethernet device
[ Upstream commit da71577545 ]

When an FDB entry is configured, the address is validated to have the
length of an Ethernet address, but the device for which the address is
configured can be of any type.

The above can result in the use of uninitialized memory when the address
is later compared against existing addresses since 'dev->addr_len' is
used and it may be greater than ETH_ALEN, as with ip6tnl devices.

Fix this by making sure that FDB entries are only configured for
Ethernet devices.

BUG: KMSAN: uninit-value in memcmp+0x11d/0x180 lib/string.c:863
CPU: 1 PID: 4318 Comm: syz-executor998 Not tainted 4.19.0-rc3+ #49
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
  __dump_stack lib/dump_stack.c:77 [inline]
  dump_stack+0x14b/0x190 lib/dump_stack.c:113
  kmsan_report+0x183/0x2b0 mm/kmsan/kmsan.c:956
  __msan_warning+0x70/0xc0 mm/kmsan/kmsan_instr.c:645
  memcmp+0x11d/0x180 lib/string.c:863
  dev_uc_add_excl+0x165/0x7b0 net/core/dev_addr_lists.c:464
  ndo_dflt_fdb_add net/core/rtnetlink.c:3463 [inline]
  rtnl_fdb_add+0x1081/0x1270 net/core/rtnetlink.c:3558
  rtnetlink_rcv_msg+0xa0b/0x1530 net/core/rtnetlink.c:4715
  netlink_rcv_skb+0x36e/0x5f0 net/netlink/af_netlink.c:2454
  rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4733
  netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
  netlink_unicast+0x1638/0x1720 net/netlink/af_netlink.c:1343
  netlink_sendmsg+0x1205/0x1290 net/netlink/af_netlink.c:1908
  sock_sendmsg_nosec net/socket.c:621 [inline]
  sock_sendmsg net/socket.c:631 [inline]
  ___sys_sendmsg+0xe70/0x1290 net/socket.c:2114
  __sys_sendmsg net/socket.c:2152 [inline]
  __do_sys_sendmsg net/socket.c:2161 [inline]
  __se_sys_sendmsg+0x2a3/0x3d0 net/socket.c:2159
  __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2159
  do_syscall_64+0xb8/0x100 arch/x86/entry/common.c:291
  entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x440ee9
Code: e8 cc ab 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 bb 0a fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff6a93b518 EFLAGS: 00000213 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000440ee9
RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000004002c8 R11: 0000000000000213 R12: 000000000000b4b0
R13: 0000000000401ec0 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
  kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline]
  kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:181
  kmsan_kmalloc+0x98/0x100 mm/kmsan/kmsan_hooks.c:91
  kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan_hooks.c:100
  slab_post_alloc_hook mm/slab.h:446 [inline]
  slab_alloc_node mm/slub.c:2718 [inline]
  __kmalloc_node_track_caller+0x9e7/0x1160 mm/slub.c:4351
  __kmalloc_reserve net/core/skbuff.c:138 [inline]
  __alloc_skb+0x2f5/0x9e0 net/core/skbuff.c:206
  alloc_skb include/linux/skbuff.h:996 [inline]
  netlink_alloc_large_skb net/netlink/af_netlink.c:1189 [inline]
  netlink_sendmsg+0xb49/0x1290 net/netlink/af_netlink.c:1883
  sock_sendmsg_nosec net/socket.c:621 [inline]
  sock_sendmsg net/socket.c:631 [inline]
  ___sys_sendmsg+0xe70/0x1290 net/socket.c:2114
  __sys_sendmsg net/socket.c:2152 [inline]
  __do_sys_sendmsg net/socket.c:2161 [inline]
  __se_sys_sendmsg+0x2a3/0x3d0 net/socket.c:2159
  __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2159
  do_syscall_64+0xb8/0x100 arch/x86/entry/common.c:291
  entry_SYSCALL_64_after_hwframe+0x63/0xe7

v2:
* Make error message more specific (David)

Fixes: 090096bf3d ("net: generic fdb support for drivers without ndo_fdb_<op>")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reported-and-tested-by: syzbot+3a288d5f5530b901310e@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+d53ab4e92a1db04110ff@syzkaller.appspotmail.com
Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-10 07:41:42 -08:00
..
datagram.c net: rename SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA 2015-12-01 15:45:05 -05:00
dev_addr_lists.c net: fix uninit-value in __hw_addr_add_ex() 2018-05-16 10:06:50 +02:00
dev_ioctl.c net: Zero terminate ifr_name in dev_ifname(). 2017-08-11 09:08:52 -07:00
dev.c net: ipv4: update fnhe_pmtu when first hop's MTU changes 2018-10-20 09:52:36 +02:00
drop_monitor.c drop_monitor: consider inserted data in genlmsg_end 2017-01-15 13:41:35 +01:00
dst_cache.c net: dst_cache_per_cpu_dst_set() can be static 2018-02-25 11:03:55 +01:00
dst.c Fix an intermittent pr_emerg warning about lo becoming free. 2017-07-05 14:37:13 +02:00
ethtool.c ethtool: do not vzalloc(0) on registers dump 2017-06-17 06:39:36 +02:00
fib_rules.c fib_rules: fix fib rule dumps across multiple skbs 2015-09-24 15:21:54 -07:00
filter.c bpf: fix 32-bit divide by zero 2018-02-03 17:04:25 +01:00
flow_dissector.c flow_dissector: properly cap thoff field 2018-01-31 12:06:14 +01:00
flow.c flow: Move __get_hash_from_flowi{4,6} into flow_dissector.c 2015-09-01 17:00:24 -07:00
gen_estimator.c net_sched: gen_estimator: extend pps limit 2015-07-08 13:59:20 -07:00
gen_stats.c
link_watch.c dev: introduce dev_get_iflink() 2015-04-02 14:04:59 -04:00
lwtunnel.c dst: Pass net into dst->output 2015-10-08 04:27:03 -07:00
Makefile net: add dst_cache support 2018-02-25 11:03:34 +01:00
neighbour.c neighbour: confirm neigh entries when ARP packet is received 2018-09-29 03:08:52 -07:00
net_namespace.c net: move somaxconn init from sysctl code 2018-04-13 19:50:11 +02:00
net-procfs.c
net-sysfs.c switchdev: rename SWITCHDEV_ATTR_* enum values to SWITCHDEV_ATTR_ID_* 2015-10-03 04:49:37 -07:00
net-sysfs.h
net-traces.c net: FIB tracepoints 2015-08-29 13:05:16 -07:00
netclassid_cgroup.c Merge branch 'master' into for-4.4-fixes 2015-12-07 10:09:03 -05:00
netevent.c netevent: remove automatic variable in register_netevent_notifier() 2015-05-31 00:03:21 -07:00
netpoll.c netpoll: Check for skb->queue_mapping 2017-05-02 21:19:53 -07:00
netprio_cgroup.c cgroup: fix handling of multi-destination migration from subtree_control enabling 2015-12-03 10:18:21 -05:00
pktgen.c net: pktgen: remove rcu locking in pktgen_change_name() 2016-11-15 07:46:38 +01:00
ptp_classifier.c ptp: Change ptp_class to a proper bitmask 2015-11-03 11:08:22 -05:00
request_sock.c tcp: restore fastopen operations 2015-10-05 03:19:06 -07:00
rtnetlink.c rtnetlink: Disallow FDB configuration for non-Ethernet device 2018-11-10 07:41:42 -08:00
scm.c unix: correctly track in-flight fds in sending process user_struct 2016-03-03 15:07:05 -08:00
secure_seq.c net: remove a sparse error in secure_dccpv6_sequence_number() 2015-05-25 22:55:37 -04:00
skbuff.c tcp: use an RB tree for ooo receive queue 2018-10-13 09:11:34 +02:00
sock_diag.c net: core: fix module type in sock_diag_bind 2018-01-17 09:35:29 +01:00
sock.c sock_diag: fix use-after-free read in __sk_free 2018-05-26 08:48:58 +02:00
stream.c net: fix sock_wake_async() rcu protection 2015-12-01 15:45:05 -05:00
sysctl_net_core.c net: move somaxconn init from sysctl code 2018-04-13 19:50:11 +02:00
timestamping.c net: skb_defer_rx_timestamp should check for phydev before setting up classify 2015-07-09 14:17:15 -07:00
tso.c net: tso: add support for IPv6 2015-10-26 22:24:22 -07:00
utils.c net: move net_get_random_once to lib 2015-10-08 05:26:35 -07:00