linux/net
Eric Dumazet 688838934c rtnetlink: ndo_dflt_fdb_dump() only work for ARPHRD_ETHER devices
kmsan was able to trigger a kernel-infoleak using a gre device [1]

nlmsg_populate_fdb_fill() has a hard coded assumption
that dev->addr_len is ETH_ALEN, as normally guaranteed
for ARPHRD_ETHER devices.

A similar issue was fixed recently in commit da71577545
("rtnetlink: Disallow FDB configuration for non-Ethernet device")

[1]
BUG: KMSAN: kernel-infoleak in copyout lib/iov_iter.c:143 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x4c0/0x2700 lib/iov_iter.c:576
CPU: 0 PID: 6697 Comm: syz-executor310 Not tainted 4.20.0-rc3+ #95
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+0x32d/0x480 lib/dump_stack.c:113
 kmsan_report+0x12c/0x290 mm/kmsan/kmsan.c:683
 kmsan_internal_check_memory+0x32a/0xa50 mm/kmsan/kmsan.c:743
 kmsan_copy_to_user+0x78/0xd0 mm/kmsan/kmsan_hooks.c:634
 copyout lib/iov_iter.c:143 [inline]
 _copy_to_iter+0x4c0/0x2700 lib/iov_iter.c:576
 copy_to_iter include/linux/uio.h:143 [inline]
 skb_copy_datagram_iter+0x4e2/0x1070 net/core/datagram.c:431
 skb_copy_datagram_msg include/linux/skbuff.h:3316 [inline]
 netlink_recvmsg+0x6f9/0x19d0 net/netlink/af_netlink.c:1975
 sock_recvmsg_nosec net/socket.c:794 [inline]
 sock_recvmsg+0x1d1/0x230 net/socket.c:801
 ___sys_recvmsg+0x444/0xae0 net/socket.c:2278
 __sys_recvmsg net/socket.c:2327 [inline]
 __do_sys_recvmsg net/socket.c:2337 [inline]
 __se_sys_recvmsg+0x2fa/0x450 net/socket.c:2334
 __x64_sys_recvmsg+0x4a/0x70 net/socket.c:2334
 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x441119
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 db 0a fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fffc7f008a8 EFLAGS: 00000207 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000441119
RDX: 0000000000000040 RSI: 00000000200005c0 RDI: 0000000000000003
RBP: 00000000006cc018 R08: 0000000000000100 R09: 0000000000000100
R10: 0000000000000100 R11: 0000000000000207 R12: 0000000000402080
R13: 0000000000402110 R14: 0000000000000000 R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:246 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:261 [inline]
 kmsan_internal_chain_origin+0x13d/0x240 mm/kmsan/kmsan.c:469
 kmsan_memcpy_memmove_metadata+0x1a9/0xf70 mm/kmsan/kmsan.c:344
 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:362
 __msan_memcpy+0x61/0x70 mm/kmsan/kmsan_instr.c:162
 __nla_put lib/nlattr.c:744 [inline]
 nla_put+0x20a/0x2d0 lib/nlattr.c:802
 nlmsg_populate_fdb_fill+0x444/0x810 net/core/rtnetlink.c:3466
 nlmsg_populate_fdb net/core/rtnetlink.c:3775 [inline]
 ndo_dflt_fdb_dump+0x73a/0x960 net/core/rtnetlink.c:3807
 rtnl_fdb_dump+0x1318/0x1cb0 net/core/rtnetlink.c:3979
 netlink_dump+0xc79/0x1c90 net/netlink/af_netlink.c:2244
 __netlink_dump_start+0x10c4/0x11d0 net/netlink/af_netlink.c:2352
 netlink_dump_start include/linux/netlink.h:216 [inline]
 rtnetlink_rcv_msg+0x141b/0x1540 net/core/rtnetlink.c:4910
 netlink_rcv_skb+0x394/0x640 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4965
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x1699/0x1740 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x13c7/0x1440 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 ___sys_sendmsg+0xe3b/0x1240 net/socket.c:2116
 __sys_sendmsg net/socket.c:2154 [inline]
 __do_sys_sendmsg net/socket.c:2163 [inline]
 __se_sys_sendmsg+0x305/0x460 net/socket.c:2161
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:246 [inline]
 kmsan_internal_poison_shadow+0x6d/0x130 mm/kmsan/kmsan.c:170
 kmsan_kmalloc+0xa1/0x100 mm/kmsan/kmsan_hooks.c:186
 __kmalloc+0x14c/0x4d0 mm/slub.c:3825
 kmalloc include/linux/slab.h:551 [inline]
 __hw_addr_create_ex net/core/dev_addr_lists.c:34 [inline]
 __hw_addr_add_ex net/core/dev_addr_lists.c:80 [inline]
 __dev_mc_add+0x357/0x8a0 net/core/dev_addr_lists.c:670
 dev_mc_add+0x6d/0x80 net/core/dev_addr_lists.c:687
 ip_mc_filter_add net/ipv4/igmp.c:1128 [inline]
 igmp_group_added+0x4d4/0xb80 net/ipv4/igmp.c:1311
 __ip_mc_inc_group+0xea9/0xf70 net/ipv4/igmp.c:1444
 ip_mc_inc_group net/ipv4/igmp.c:1453 [inline]
 ip_mc_up+0x1c3/0x400 net/ipv4/igmp.c:1775
 inetdev_event+0x1d03/0x1d80 net/ipv4/devinet.c:1522
 notifier_call_chain kernel/notifier.c:93 [inline]
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x13d/0x240 kernel/notifier.c:401
 __dev_notify_flags+0x3da/0x860 net/core/dev.c:1733
 dev_change_flags+0x1ac/0x230 net/core/dev.c:7569
 do_setlink+0x165f/0x5ea0 net/core/rtnetlink.c:2492
 rtnl_newlink+0x2ad7/0x35a0 net/core/rtnetlink.c:3111
 rtnetlink_rcv_msg+0x1148/0x1540 net/core/rtnetlink.c:4947
 netlink_rcv_skb+0x394/0x640 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4965
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x1699/0x1740 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x13c7/0x1440 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 ___sys_sendmsg+0xe3b/0x1240 net/socket.c:2116
 __sys_sendmsg net/socket.c:2154 [inline]
 __do_sys_sendmsg net/socket.c:2163 [inline]
 __se_sys_sendmsg+0x305/0x460 net/socket.c:2161
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Bytes 36-37 of 105 are uninitialized
Memory access of size 105 starts at ffff88819686c000
Data copied to user address 0000000020000380

Fixes: d83b060360 ("net: add fdb generic dump routine")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Ido Schimmel <idosch@mellanox.com>
Cc: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-04 20:28:22 -08:00
..
6lowpan
9p Merge branch 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-11-03 10:35:52 -07:00
802
8021q netpoll: allow cleanup to be synchronous 2018-10-19 17:01:43 -07:00
appletalk
atm Revert "net: simplify sock_poll_wait" 2018-10-23 10:57:06 -07:00
ax25
batman-adv batman-adv: Expand merged fragment buffer for full packet 2018-11-12 10:41:29 +01:00
bluetooth Merge branch 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-11-01 19:58:52 -07:00
bpf bpf: add tests for direct packet access from CGROUP_SKB 2018-10-19 13:49:34 -07:00
bpfilter net: bpfilter: Set user mode helper's command line 2018-10-22 19:37:36 -07:00
bridge net: bridge: fix vlan stats use-after-free on destruction 2018-11-17 21:38:44 -08:00
caif Revert "net: simplify sock_poll_wait" 2018-10-23 10:57:06 -07:00
can can: raw: check for CAN FD capable netdev in raw_sendmsg() 2018-11-09 17:19:34 +01:00
ceph libceph: fall back to sendmsg for slab pages 2018-11-19 17:59:47 +01:00
core rtnetlink: ndo_dflt_fdb_dump() only work for ARPHRD_ETHER devices 2018-12-04 20:28:22 -08:00
dcb
dccp Revert "net: simplify sock_poll_wait" 2018-10-23 10:57:06 -07:00
decnet
dns_resolver dns: Allow the dns resolver to retrieve a server set 2018-10-04 09:40:52 -07:00
dsa net: dsa: Fix tagging attribute location 2018-11-30 17:17:39 -08:00
ethernet
hsr
ieee802154
ife
ipv4 tcp: fix SNMP TCP timeout under-estimation 2018-11-30 17:22:41 -08:00
ipv6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2018-11-28 11:02:45 -08:00
iucv Revert "net: simplify sock_poll_wait" 2018-10-23 10:57:06 -07:00
kcm
key
l2tp l2tp: fix a sock refcnt leak in l2tp_tunnel_register 2018-11-14 22:49:31 -08:00
l3mdev
lapb
llc llc: do not use sk_eat_skb() 2018-10-22 19:59:20 -07:00
mac80211 mac80211: implement ieee80211_tx_rate_update to update rate 2018-10-12 13:05:40 +02:00
mac802154 mac802154: Remove VLA usage of skcipher 2018-09-28 12:46:07 +08:00
mpls net/mpls: Handle kernel side filtering of route dumps 2018-10-16 00:14:07 -07:00
ncsi net/ncsi: Add NCSI Broadcom OEM command 2018-10-17 22:14:54 -07:00
netfilter netfilter: nf_tables: deactivate expressions in rule replecement routine 2018-11-28 10:56:40 +01:00
netlabel
netlink netlink: Add answer_flags to netlink_callback 2018-10-16 00:13:12 -07:00
netrom
nfc Merge branch 'work.tty-ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-10-24 14:43:41 +01:00
nsh
openvswitch openvswitch: fix spelling mistake "execeeds" -> "exceeds" 2018-11-30 13:18:09 -08:00
packet packet: copy user buffers before orphan or clone 2018-11-23 11:08:03 -08:00
phonet
psample
qrtr
rds Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-10-12 21:38:46 -07:00
rfkill
rose
rxrpc rxrpc: Fix life check 2018-11-15 11:35:40 -08:00
sched net/sched: act_police: fix memory leak in case of invalid control action 2018-11-30 17:14:06 -08:00
sctp sctp: kfree_rcu asoc 2018-12-03 15:54:41 -08:00
smc net/smc: use after free fix in smc_wr_tx_put_slot() 2018-11-21 16:14:56 -08:00
strparser bpf, sockmap: convert to generic sk_msg interface 2018-10-15 12:23:19 -07:00
sunrpc NFS client bugfixes for Linux 4.20 2018-11-15 10:59:37 -06:00
switchdev
tipc tipc: fix lockdep warning during node delete 2018-11-27 16:30:39 -08:00
tls Merge branch 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-11-01 19:58:52 -07:00
unix Revert "net: simplify sock_poll_wait" 2018-10-23 10:57:06 -07:00
vmw_vsock
wimax
wireless nl80211: Add per peer statistics to compute FCS error rate 2018-10-12 12:56:34 +02:00
x25 net/x25: handle call collisions 2018-11-29 14:25:36 -08:00
xdp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-10-19 11:03:06 -07:00
xfrm Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-11-03 18:25:17 -07:00
compat.c
Kconfig bpf, sockmap: convert to generic sk_msg interface 2018-10-15 12:23:19 -07:00
Makefile
socket.c socket: do a generic_file_splice_read when proto_ops has no splice_read 2018-11-17 21:34:11 -08:00
sysctl_net.c