linux/net/core
Ido Schimmel da71577545 rtnetlink: Disallow FDB configuration for non-Ethernet device
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>
2018-10-29 20:52:35 -07:00
..
datagram.c net: udp: fix handling of CHECKSUM_COMPLETE packets 2018-10-24 14:18:16 -07:00
dev_addr_lists.c net: change the comment of dev_mc_init 2018-04-19 12:58:20 -04:00
dev_ioctl.c net: remove redundant input checks in SIOCSIFTXQLEN case of dev_ifsioc 2018-07-24 11:36:15 -07:00
dev.c net: Properly unlink GRO packets on overflow. 2018-10-28 10:35:12 -07:00
devlink.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-10-12 21:38:46 -07:00
drop_monitor.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
dst_cache.c net: core: dst_cache_set_ip6: Rename 'addr' parameter to 'saddr' for consistency 2018-03-05 12:52:45 -05:00
dst.c netfilter: nf_tables: add tunnel support 2018-08-03 21:12:12 +02:00
ethtool.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-10-19 11:03:06 -07:00
failover.c net: Introduce generic failover module 2018-05-28 22:59:54 -04:00
fib_notifier.c net: Fix fib notifer to return errno 2018-03-29 14:10:30 -04:00
fib_rules.c net/fib_rules: Update fib_nl_dumprule for strict data checking 2018-10-08 10:39:05 -07:00
filter.c bpf: fix wrong helper enablement in cgroup local storage 2018-10-26 16:03:30 -07:00
flow_dissector.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2018-09-25 20:29:38 -07:00
gen_estimator.c net: core: protect rate estimator statistics pointer with lock 2018-08-11 12:37:10 -07:00
gen_stats.c net/core: make function ___gnet_stats_copy_basic() static 2018-09-28 10:25:11 -07:00
gro_cells.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
hwbm.c net: hwbm: Fix unbalanced spinlock in error case 2016-05-25 12:35:09 -07:00
link_watch.c net: linkwatch: add check for netdevice being present to linkwatch_do_dev 2018-09-19 21:06:46 -07:00
lwt_bpf.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2018-08-07 11:02:05 -07:00
lwtunnel.c ipv6: sr: define core operations for seg6local lightweight tunnel 2017-08-07 14:16:22 -07:00
Makefile bpf, sockmap: convert to generic sk_msg interface 2018-10-15 12:23:19 -07:00
neighbour.c net/neigh: fix NULL deref in pneigh_dump_table() 2018-10-26 16:03:51 -07:00
net_namespace.c net/namespace: Update rtnl_net_dumpid for strict data checking 2018-10-08 10:39:05 -07:00
net-procfs.c proc: introduce proc_create_net{,_data} 2018-05-16 07:24:30 +02:00
net-sysfs.c net: allow to call netif_reset_xps_queues() under cpus_read_lock 2018-08-09 14:25:06 -07:00
net-sysfs.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
net-traces.c net/ipv6: Udate fib6_table_lookup tracepoint 2018-05-24 23:01:15 -04:00
netclassid_cgroup.c cgroup, netclassid: add a preemption point to write_classid 2018-10-23 12:58:17 -07:00
netevent.c netevent: remove automatic variable in register_netevent_notifier() 2015-05-31 00:03:21 -07:00
netpoll.c netpoll: allow cleanup to be synchronous 2018-10-19 17:01:43 -07:00
netprio_cgroup.c net: remove duplicate includes 2017-12-13 13:18:46 -05:00
page_pool.c net/page_pool: Fix inconsistent lock state warning 2018-07-19 23:23:01 -07:00
pktgen.c pktgen: Fix fall-through annotation 2018-09-13 15:36:41 -07:00
ptp_classifier.c ptp: Change ptp_class to a proper bitmask 2015-11-03 11:08:22 -05:00
request_sock.c ipv4: Namespaceify tcp_max_syn_backlog knob 2016-12-29 11:38:31 -05:00
rtnetlink.c rtnetlink: Disallow FDB configuration for non-Ethernet device 2018-10-29 20:52:35 -07:00
scm.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/user.h> 2017-03-02 08:42:29 +01:00
secure_seq.c infiniband: i40iw, nes: don't use wall time for TCP sequence numbers 2018-07-11 12:10:19 -06:00
skbuff.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-10-21 11:54:28 -07:00
skmsg.c tls: convert to generic sk_msg interface 2018-10-15 12:23:19 -07:00
sock_diag.c net: sock_diag: Fix spectre v1 gadget in __sock_diag_cmd() 2018-08-14 10:01:24 -07:00
sock_map.c bpf: skmsg, fix psock create on existing kcm/tls port 2018-10-20 00:40:45 +02:00
sock_reuseport.c bpf: Enable BPF_PROG_TYPE_SK_REUSEPORT bpf prog in reuseport selection 2018-08-11 01:58:46 +02:00
sock.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2018-10-15 23:21:07 -07:00
stream.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
sysctl_net_core.c bpf: add bpf_jit_limit knob to restrict unpriv allocations 2018-10-25 17:11:42 -07:00
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 License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
utils.c net: Remove some unneeded semicolon 2018-08-04 13:05:39 -07:00
xdp.c xdp: remove redundant variable 'headroom' 2018-09-01 01:35:53 +02:00