Eric Dumazet 753aa75560 neigh: fix use-after-free read in pneigh_get_next ... [ Upstream commit f3e92cb8e2eb8c27d109e6fd73d3a69a8c09e288 ] 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 08:18:25 +02:00
..
6lowpan	6lowpan: iphc: reset mac_header after decompress to fix panic	2018-10-10 08:52:04 +02:00
9p	9p: do not trust pdu content for stat item size	2019-04-27 09:33:58 +02:00
802
8021q	vlan: disable SIOCSHWTSTAMP in container	2019-05-16 19:45:17 +02:00
appletalk	appletalk: Fix use-after-free in atalk_proc_exit	2019-04-27 09:33:59 +02:00
atm	net: atm: Fix potential Spectre v1 vulnerabilities	2019-04-27 09:33:59 +02:00
ax25	ax25: fix inconsistent lock state in ax25_destroy_timer	2019-06-22 08:18:25 +02:00
batman-adv	batman-adv: fix uninit-value in batadv_interface_tx()	2019-03-23 08:44:17 +01:00
bluetooth	Revert "Bluetooth: Align minimum encryption key size for LE and BR/EDR connections"	2019-06-22 08:18:22 +02:00
bridge	bridge: Fix error path for kobject_init_and_add()	2019-05-16 19:45:17 +02:00
caif	net: caif: Add a missing rcu_read_unlock() in caif_flow_cb	2018-09-05 09:18:34 +02:00
can	can: bcm: check timer values before ktime conversion	2019-02-06 19:43:04 +01:00
ceph	libceph: handle an empty authorize reply	2019-03-23 08:44:18 +01:00
core	neigh: fix use-after-free read in pneigh_get_next	2019-06-22 08:18:25 +02:00
dcb	net: dcb: For wild-card lookups, use priority -1, not 0	2018-09-19 22:48:58 +02:00
dccp	dccp: do not use ipv6 header for ipv4 flow	2019-04-03 06:23:25 +02:00
decnet	dn_getsockoptdecnet: move nf_{get/set}sockopt outside sock lock	2018-02-25 11:03:38 +01:00
dns_resolver	KEYS: DNS: fix parsing multiple options	2018-07-22 14:25:54 +02:00
dsa	net: dsa: slave: Don't propagate flag changes on down slave interfaces	2019-02-20 10:13:15 +01:00
ethernet	net: introduce device min_header_len	2017-02-18 16:39:27 +01:00
hsr	net/hsr: fix possible crash in add_timer()	2019-03-23 08:44:31 +01:00
ieee802154	inet: frags: fix ip6frag_low_thresh boundary	2019-02-08 11:25:32 +01:00
ipv4	tcp: enforce tcp_min_snd_mss in tcp_mtu_probing()	2019-06-17 19:54:22 +02:00
ipv6	ipv6: flowlabel: fl6_sock_lookup() must use atomic_inc_not_zero	2019-06-22 08:18:25 +02:00
ipx	ipx: call ipxitf_put() in ioctl error path	2017-05-25 14:30:13 +02:00
irda	irda: Only insert new objects into the global database via setsockopt	2018-09-15 09:40:40 +02:00
iucv	af_iucv: Move sockaddr length checks to before accessing sa_family in bind and connect handlers	2018-11-10 07:41:35 -08:00
key	af_key: Always verify length of provided sadb_key	2018-06-16 09:54:25 +02:00
l2tp	l2tp: fix infoleak in l2tp_ip6_recvmsg()	2019-03-23 08:44:29 +01:00
l3mdev	net: Add netif_is_l3_slave	2015-10-07 04:27:43 -07:00
lapb	lapb: fixed leak of control-blocks.	2019-06-22 08:18:25 +02:00
llc	llc: fix skb leak in llc_build_and_send_ui_pkt()	2019-06-11 12:24:06 +02:00
mac80211	mac80211/cfg80211: update bss channel on channel switch	2019-06-11 12:23:55 +02:00
mac802154	net: mac802154: tx: expand tailroom if necessary	2018-09-09 20:04:32 +02:00
mpls	mpls, nospec: Sanitize array index in mpls_label_ok()	2018-03-11 16:19:47 +01:00
netfilter	ipvs: do not schedule icmp errors from tunnels	2019-05-16 19:45:06 +02:00
netlabel	netlabel: check for IPV4MASK in addrinfo_get	2018-10-20 09:52:36 +02:00
netlink	netlink: Don't shift on 64 for ngroups	2018-08-09 12:19:28 +02:00
netrom	netrom: switch to sock timer API	2019-02-06 19:43:06 +01:00
nfc	net: nfc: Fix NULL dereference on nfc_llcp_build_tlv fails	2019-03-23 08:44:22 +01:00
openvswitch	openvswitch: fix flow actions reallocation	2019-04-27 09:33:54 +02:00
packet	packet: Fix error path in packet_init	2019-05-16 19:45:17 +02:00
phonet	phonet: fix building with clang	2019-03-23 08:44:34 +01:00
rds	net: rds: fix memory leak in rds_ib_flush_mr_pool	2019-06-11 12:24:12 +02:00
rfkill	rfkill: gpio: fix memory leak in probe error path	2018-05-16 10:06:51 +02:00
rose	net: rose: fix a possible stack overflow	2019-04-03 06:23:25 +02:00
rxrpc	rxrpc: check return value of skb_to_sgvec always	2018-04-13 19:50:23 +02:00
sched	net: create skb_gso_validate_mac_len()	2019-06-11 12:24:10 +02:00
sctp	sctp: initialize _pad of sockaddr_in before copying to user memory	2019-04-27 09:33:55 +02:00
sunrpc	sunrpc: don't mark uninitialised items as VALID.	2019-05-16 19:44:44 +02:00
switchdev	switchdev: pass pointer to fib_info instead of copy	2016-06-24 10:18:16 -07:00
tipc	tipc: fix modprobe tipc failed after switch order of device registration -v2	2019-06-11 12:24:07 +02:00
unix	missing barriers in some of unix_sock ->addr and ->path accesses	2019-03-23 08:44:31 +01:00
vmw_vsock	vsock: cope with memory allocation failure at socket creation time	2019-02-23 09:05:13 +01:00
wimax	net:wimax: Fix doucble word "the the" in networking.xml	2015-08-09 22:43:52 -07:00
wireless	mac80211/cfg80211: update bss channel on channel switch	2019-06-11 12:23:55 +02:00
x25	net/x25: fix a race in x25_bind()	2019-03-23 08:44:30 +01:00
xfrm	xfrm: policy: Fix out-of-bound array accesses in __xfrm_policy_unlink	2019-06-11 12:23:48 +02:00
compat.c	sock: Make sock->sk_stamp thread-safe	2019-01-13 10:05:28 +01:00
Kconfig	Make DST_CACHE a silent config option	2018-02-25 11:03:37 +01:00
Makefile	net: Introduce L3 Master device abstraction	2015-09-29 20:40:32 -07:00
socket.c	sockfs: getxattr: Fail with -EOPNOTSUPP for invalid attribute names	2019-03-23 08:44:21 +01:00
sysctl_net.c	net: Use ns_capable_noaudit() when determining net sysctl permissions	2016-09-15 08:27:50 +02:00