linux-uconsole/net
Eric Dumazet 103835df68 neigh: fix use-after-free read in pneigh_get_next
[ Upstream commit f3e92cb8e2 ]

Nine years ago, I added RCU handling to neighbours, not pneighbours.
(pneigh are not commonly used)

Unfortunately I missed that /proc dump operations would use a
common entry and exit point : neigh_seq_start() and neigh_seq_stop()

We need to read_lock(tbl->lock) or risk use-after-free while
iterating the pneigh structures.

We might later convert pneigh to RCU and revert this patch.

sysbot reported :

BUG: KASAN: use-after-free in pneigh_get_next.isra.0+0x24b/0x280 net/core/neighbour.c:3158
Read of size 8 at addr ffff888097f2a700 by task syz-executor.0/9825

CPU: 1 PID: 9825 Comm: syz-executor.0 Not tainted 5.2.0-rc4+ #32
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+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:188
 __kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 kasan_report+0x12/0x20 mm/kasan/common.c:614
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132
 pneigh_get_next.isra.0+0x24b/0x280 net/core/neighbour.c:3158
 neigh_seq_next+0xdb/0x210 net/core/neighbour.c:3240
 seq_read+0x9cf/0x1110 fs/seq_file.c:258
 proc_reg_read+0x1fc/0x2c0 fs/proc/inode.c:221
 do_loop_readv_writev fs/read_write.c:714 [inline]
 do_loop_readv_writev fs/read_write.c:701 [inline]
 do_iter_read+0x4a4/0x660 fs/read_write.c:935
 vfs_readv+0xf0/0x160 fs/read_write.c:997
 kernel_readv fs/splice.c:359 [inline]
 default_file_splice_read+0x475/0x890 fs/splice.c:414
 do_splice_to+0x127/0x180 fs/splice.c:877
 splice_direct_to_actor+0x2d2/0x970 fs/splice.c:954
 do_splice_direct+0x1da/0x2a0 fs/splice.c:1063
 do_sendfile+0x597/0xd00 fs/read_write.c:1464
 __do_sys_sendfile64 fs/read_write.c:1525 [inline]
 __se_sys_sendfile64 fs/read_write.c:1511 [inline]
 __x64_sys_sendfile64+0x1dd/0x220 fs/read_write.c:1511
 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4592c9
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f4aab51dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000004592c9
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000005
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000080000000 R11: 0000000000000246 R12: 00007f4aab51e6d4
R13: 00000000004c689d R14: 00000000004db828 R15: 00000000ffffffff

Allocated by task 9827:
 save_stack+0x23/0x90 mm/kasan/common.c:71
 set_track mm/kasan/common.c:79 [inline]
 __kasan_kmalloc mm/kasan/common.c:489 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:503
 __do_kmalloc mm/slab.c:3660 [inline]
 __kmalloc+0x15c/0x740 mm/slab.c:3669
 kmalloc include/linux/slab.h:552 [inline]
 pneigh_lookup+0x19c/0x4a0 net/core/neighbour.c:731
 arp_req_set_public net/ipv4/arp.c:1010 [inline]
 arp_req_set+0x613/0x720 net/ipv4/arp.c:1026
 arp_ioctl+0x652/0x7f0 net/ipv4/arp.c:1226
 inet_ioctl+0x2a0/0x340 net/ipv4/af_inet.c:926
 sock_do_ioctl+0xd8/0x2f0 net/socket.c:1043
 sock_ioctl+0x3ed/0x780 net/socket.c:1194
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:696
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 9824:
 save_stack+0x23/0x90 mm/kasan/common.c:71
 set_track mm/kasan/common.c:79 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459
 __cache_free mm/slab.c:3432 [inline]
 kfree+0xcf/0x220 mm/slab.c:3755
 pneigh_ifdown_and_unlock net/core/neighbour.c:812 [inline]
 __neigh_ifdown+0x236/0x2f0 net/core/neighbour.c:356
 neigh_ifdown+0x20/0x30 net/core/neighbour.c:372
 arp_ifdown+0x1d/0x21 net/ipv4/arp.c:1274
 inetdev_destroy net/ipv4/devinet.c:319 [inline]
 inetdev_event+0xa14/0x11f0 net/ipv4/devinet.c:1544
 notifier_call_chain+0xc2/0x230 kernel/notifier.c:95
 __raw_notifier_call_chain kernel/notifier.c:396 [inline]
 raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:403
 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1749
 call_netdevice_notifiers_extack net/core/dev.c:1761 [inline]
 call_netdevice_notifiers net/core/dev.c:1775 [inline]
 rollback_registered_many+0x9b9/0xfc0 net/core/dev.c:8178
 rollback_registered+0x109/0x1d0 net/core/dev.c:8220
 unregister_netdevice_queue net/core/dev.c:9267 [inline]
 unregister_netdevice_queue+0x1ee/0x2c0 net/core/dev.c:9260
 unregister_netdevice include/linux/netdevice.h:2631 [inline]
 __tun_detach+0xd8a/0x1040 drivers/net/tun.c:724
 tun_detach drivers/net/tun.c:741 [inline]
 tun_chr_close+0xe0/0x180 drivers/net/tun.c:3451
 __fput+0x2ff/0x890 fs/file_table.c:280
 ____fput+0x16/0x20 fs/file_table.c:313
 task_work_run+0x145/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:185 [inline]
 exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:168
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
 do_syscall_64+0x58e/0x680 arch/x86/entry/common.c:304
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff888097f2a700
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 0 bytes inside of
 64-byte region [ffff888097f2a700, ffff888097f2a740)
The buggy address belongs to the page:
page:ffffea00025fca80 refcount:1 mapcount:0 mapping:ffff8880aa400340 index:0x0
flags: 0x1fffc0000000200(slab)
raw: 01fffc0000000200 ffffea000250d548 ffffea00025726c8 ffff8880aa400340
raw: 0000000000000000 ffff888097f2a000 0000000100000020 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888097f2a600: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
 ffff888097f2a680: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff888097f2a700: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                   ^
 ffff888097f2a780: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff888097f2a800: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc

Fixes: 767e97e1e0 ("neigh: RCU conversion of struct neighbour")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-22 08:15:13 +02:00
..
6lowpan 6lowpan: iphc: reset mac_header after decompress to fix panic 2018-07-06 12:32:12 +02:00
9p 9p: do not trust pdu content for stat item size 2019-04-20 09:16:00 +02:00
802
8021q vlan: disable SIOCSHWTSTAMP in container 2019-05-16 19:41:30 +02:00
appletalk appletalk: Fix use-after-free in atalk_proc_exit 2019-04-20 09:16:05 +02:00
atm net: atm: Fix potential Spectre v1 vulnerabilities 2019-04-27 09:36:30 +02:00
ax25 ax25: fix inconsistent lock state in ax25_destroy_timer 2019-06-22 08:15:13 +02:00
batman-adv batman-adv: allow updating DAT entry timeouts on incoming ARP Replies 2019-05-31 06:46:31 -07:00
bluetooth Revert "Bluetooth: Align minimum encryption key size for LE and BR/EDR connections" 2019-06-15 11:54:11 +02:00
bpf bpf/test_run: support cgroup local storage 2018-08-03 00:47:32 +02:00
bpfilter net: bpfilter: use get_pid_task instead of pid_task 2018-10-17 22:03:40 -07:00
bridge bridge: Fix error path for kobject_init_and_add() 2019-05-16 19:41:29 +02:00
caif Revert "net: simplify sock_poll_wait" 2018-11-04 14:50:51 +01:00
can can: bcm: check timer values before ktime conversion 2019-01-31 08:14:39 +01:00
ceph libceph: wait for latest osdmap in ceph_monc_blacklist_add() 2019-03-27 14:14:39 +09:00
core neigh: fix use-after-free read in pneigh_get_next 2019-06-22 08:15:13 +02:00
dcb net: dcb: Add priority-to-DSCP map getters 2018-07-27 13:17:50 -07:00
dccp dccp: do not use ipv6 header for ipv4 flow 2019-04-03 06:26:15 +02:00
decnet decnet: fix using plain integer as NULL warning 2018-08-09 14:11:24 -07:00
dns_resolver net: remove blank lines at end of file 2018-07-24 14:10:43 -07:00
dsa net: dsa: Fix error cleanup path in dsa_init_module 2019-05-16 19:41:29 +02:00
ethernet net: Convert GRO SKB handling to list_head. 2018-06-26 11:33:04 +09:00
hsr net/hsr: fix possible crash in add_timer() 2019-03-19 13:12:38 +01:00
ieee802154 ieee802154: lowpan_header_create check must check daddr 2019-01-09 17:38:31 +01:00
ife
ipv4 tcp: enforce tcp_min_snd_mss in tcp_mtu_probing() 2019-06-17 19:51:56 +02:00
ipv6 ipv6: flowlabel: fl6_sock_lookup() must use atomic_inc_not_zero 2019-06-22 08:15:13 +02:00
iucv Revert "net: simplify sock_poll_wait" 2018-11-04 14:50:51 +01:00
kcm kcm: switch order of device registration to fix a crash 2019-04-17 08:38:40 +02:00
key xfrm: clean up xfrm protocol checks 2019-05-25 18:23:41 +02:00
l2tp l2tp: use rcu_dereference_sk_user_data() in l2tp_udp_encap_recv() 2019-05-05 14:42:37 +02:00
l3mdev
lapb lapb: fixed leak of control-blocks. 2019-06-22 08:15:13 +02:00
llc llc: fix skb leak in llc_build_and_send_ui_pkt() 2019-06-04 08:02:31 +02:00
mac80211 mac80211/cfg80211: update bss channel on channel switch 2019-05-31 06:46:14 -07:00
mac802154 net: mac802154: tx: expand tailroom if necessary 2018-08-06 11:21:37 +02:00
mpls mpls: Return error for RTA_GATEWAY attribute 2019-03-10 07:17:19 +01:00
ncsi net/ncsi: Fixup .dumpit message flags and ID check in Netlink handler 2018-08-22 21:39:08 -07:00
netfilter netfilter: nf_flow_table: fix netdev refcnt leak 2019-06-15 11:54:06 +02:00
netlabel netlabel: fix out-of-bounds memory accesses 2019-03-10 07:17:18 +01:00
netlink genetlink: Fix a memory leak on error path 2019-04-03 06:26:15 +02:00
netrom net: netrom: Fix error cleanup path of nr_proto_init 2019-05-02 09:58:57 +02:00
nfc NFC: nci: Add some bounds checking in nci_hci_cmd_received() 2019-05-16 19:41:27 +02:00
nsh nsh: set mac len based on inner packet 2018-07-12 16:55:29 -07:00
openvswitch openvswitch: fix flow actions reallocation 2019-04-17 08:38:41 +02:00
packet packet: unconditionally free po->rollover 2019-06-11 12:20:49 +02:00
phonet phonet: fix building with clang 2019-03-23 20:09:51 +01:00
psample
qrtr net: qrtr: Reset the node and port ID of broadcast messages 2018-07-05 20:20:03 +09:00
rds net: rds: fix memory leak in rds_ib_flush_mr_pool 2019-06-11 12:20:49 +02:00
rfkill Here are quite a large number of fixes, notably: 2018-09-03 22:12:02 -07:00
rose net/rose: fix unbound loop in rose_loopback_timer() 2019-05-02 09:59:00 +02:00
rxrpc rxrpc: Fix net namespace cleanup 2019-05-05 14:42:38 +02:00
sched net: sched: don't use tc_action->order during action dump 2019-06-04 08:02:32 +02:00
sctp Fix memory leak in sctp_process_init 2019-06-11 12:20:47 +02:00
smc net/smc: fix smc_poll in SMC_INIT state 2019-03-19 13:12:41 +01:00
strparser net: strparser: partially revert "strparser: Call skb_unclone conditionally" 2019-05-16 19:41:27 +02:00
sunrpc sunrpc: don't mark uninitialised items as VALID. 2019-05-02 09:58:55 +02:00
switchdev
tipc tipc: fix modprobe tipc failed after switch order of device registration 2019-06-04 08:02:34 +02:00
tls net/tls: replace the sleeping lock around RX resync with a bit lock 2019-06-11 12:20:49 +02:00
unix missing barriers in some of unix_sock ->addr and ->path accesses 2019-03-19 13:12:41 +01:00
vmw_vsock vsock/virtio: Initialize core virtio vsock before registering the driver 2019-05-25 18:23:22 +02:00
wimax wimax: remove blank lines at EOF 2018-07-24 14:10:42 -07:00
wireless mac80211/cfg80211: update bss channel on channel switch 2019-05-31 06:46:14 -07:00
x25 net/x25: fix a race in x25_bind() 2019-03-19 13:12:40 +01:00
xdp xsk: fix umem memory leak on cleanup 2019-05-04 09:20:12 +02:00
xfrm xfrm: Honor original L3 slave device in xfrmi policy lookup 2019-05-25 18:23:41 +02:00
compat.c sock: Make sock->sk_stamp thread-safe 2019-01-09 17:38:33 +01:00
Kconfig net: remove blank lines at end of file 2018-07-24 14:10:43 -07:00
Makefile bpfilter: check compiler capability in Kconfig 2018-06-28 13:36:39 +09:00
socket.c net: socket: set sock->sk to NULL after calling proto_ops::release() 2019-03-10 07:17:18 +01:00
sysctl_net.c