Eric Dumazet 63530aba78 ax25: fix possible use-after-free ... syzbot found that ax25 routes where not properly protected against concurrent use [1]. In this particular report the bug happened while copying ax25->digipeat. Fix this problem by making sure we call ax25_get_route() while ax25_route_lock is held, so that no modification could happen while using the route. The current two ax25_get_route() callers do not sleep, so this change should be fine. Once we do that, ax25_get_route() no longer needs to grab a reference on the found route. [1] ax25_connect(): syz-executor0 uses autobind, please contact jreuter@yaina.de BUG: KASAN: use-after-free in memcpy include/linux/string.h:352 [inline] BUG: KASAN: use-after-free in kmemdup+0x42/0x60 mm/util.c:113 Read of size 66 at addr ffff888066641a80 by task syz-executor2/531 ax25_connect(): syz-executor0 uses autobind, please contact jreuter@yaina.de CPU: 1 PID: 531 Comm: syz-executor2 Not tainted 5.0.0-rc2+ #10 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+0x1db/0x2d0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x123/0x190 mm/kasan/generic.c:191 memcpy+0x24/0x50 mm/kasan/common.c:130 memcpy include/linux/string.h:352 [inline] kmemdup+0x42/0x60 mm/util.c:113 kmemdup include/linux/string.h:425 [inline] ax25_rt_autobind+0x25d/0x750 net/ax25/ax25_route.c:424 ax25_connect.cold+0x30/0xa4 net/ax25/af_ax25.c:1224 __sys_connect+0x357/0x490 net/socket.c:1664 __do_sys_connect net/socket.c:1675 [inline] __se_sys_connect net/socket.c:1672 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:1672 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458099 Code: 6d 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 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f870ee22c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458099 RDX: 0000000000000048 RSI: 0000000020000080 RDI: 0000000000000005 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 ax25_connect(): syz-executor4 uses autobind, please contact jreuter@yaina.de R10: 0000000000000000 R11: 0000000000000246 R12: 00007f870ee236d4 R13: 00000000004be48e R14: 00000000004ce9a8 R15: 00000000ffffffff Allocated by task 526: save_stack+0x45/0xd0 mm/kasan/common.c:73 set_track mm/kasan/common.c:85 [inline] __kasan_kmalloc mm/kasan/common.c:496 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:469 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:504 ax25_connect(): syz-executor5 uses autobind, please contact jreuter@yaina.de kmem_cache_alloc_trace+0x151/0x760 mm/slab.c:3609 kmalloc include/linux/slab.h:545 [inline] ax25_rt_add net/ax25/ax25_route.c:95 [inline] ax25_rt_ioctl+0x3b9/0x1270 net/ax25/ax25_route.c:233 ax25_ioctl+0x322/0x10b0 net/ax25/af_ax25.c:1763 sock_do_ioctl+0xe2/0x400 net/socket.c:950 sock_ioctl+0x32f/0x6c0 net/socket.c:1074 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0x107b/0x17d0 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+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe ax25_connect(): syz-executor5 uses autobind, please contact jreuter@yaina.de Freed by task 550: save_stack+0x45/0xd0 mm/kasan/common.c:73 set_track mm/kasan/common.c:85 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:458 kasan_slab_free+0xe/0x10 mm/kasan/common.c:466 __cache_free mm/slab.c:3487 [inline] kfree+0xcf/0x230 mm/slab.c:3806 ax25_rt_add net/ax25/ax25_route.c:92 [inline] ax25_rt_ioctl+0x304/0x1270 net/ax25/ax25_route.c:233 ax25_ioctl+0x322/0x10b0 net/ax25/af_ax25.c:1763 sock_do_ioctl+0xe2/0x400 net/socket.c:950 sock_ioctl+0x32f/0x6c0 net/socket.c:1074 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0x107b/0x17d0 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+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888066641a80 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes inside of 96-byte region [ffff888066641a80, ffff888066641ae0) The buggy address belongs to the page: page:ffffea0001999040 count:1 mapcount:0 mapping:ffff88812c3f04c0 index:0x0 flags: 0x1fffc0000000200(slab) ax25_connect(): syz-executor4 uses autobind, please contact jreuter@yaina.de raw: 01fffc0000000200 ffffea0001817948 ffffea0002341dc8 ffff88812c3f04c0 raw: 0000000000000000 ffff888066641000 0000000100000020 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888066641980: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888066641a00: 00 00 00 00 00 00 00 00 02 fc fc fc fc fc fc fc >ffff888066641a80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff888066641b00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888066641b80: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Ralf Baechle <ralf@linux-mips.org> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2019-01-23 11:18:00 -08:00
..
9p	…
bluetooth	Bluetooth: Errata Service Release 8, Erratum 3253	2018-10-14 10:25:47 +02:00
caif	…
iucv	…
netfilter	netfilter: nft_flow_offload: fix interaction with vrf slave device	2019-01-11 00:55:37 +01:00
netns	Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next	2018-12-20 18:20:26 -08:00
nfc	…
phonet	…
sctp	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2018-12-09 21:43:31 -08:00
tc_act	…
6lowpan.h	…
Space.h	…
act_api.h	net/sched: Remove egdev mechanism	2018-12-10 15:54:34 -08:00
addrconf.h	net/ipv6: Add anycast addresses to a global hashtable	2018-11-02 23:54:56 -07:00
af_ieee802154.h	…
af_rxrpc.h	Revert "rxrpc: Allow failed client calls to be retried"	2019-01-15 21:33:36 -08:00
af_unix.h	net: drop a space before tabs	2018-10-31 12:37:12 -07:00
af_vsock.h	…
ah.h	…
arp.h	…
atmclip.h	…
ax25.h	ax25: fix possible use-after-free	2019-01-23 11:18:00 -08:00
ax88796.h	…
bond_3ad.h	…
bond_alb.h	…
bond_options.h	…
bonding.h	…
busy_poll.h	…
calipso.h	…
cfg80211-wext.h	…
cfg80211.h	cfg80211: clarify LCI/civic location documentation	2018-12-18 13:15:04 +01:00
cfg802154.h	…
checksum.h	Remove 'type' argument from access_ok() function	2019-01-03 18:57:57 -08:00
cipso_ipv4.h	…
cls_cgroup.h	…
codel.h	…
codel_impl.h	…
codel_qdisc.h	…
compat.h	…
datalink.h	…
dcbevent.h	…
dcbnl.h	…
devlink.h	devlink: Add 'fw_load_policy' generic parameter	2018-12-03 13:55:43 -08:00
dn.h	…
dn_dev.h	…
dn_fib.h	…
dn_neigh.h	…
dn_nsp.h	…
dn_route.h	…
dsa.h	net: dsa: ksz: Rename NET_DSA_TAG_KSZ to _KSZ9477	2018-12-16 14:23:33 -08:00
dsfield.h	…
dst.h	geneve, vxlan: Don't set exceptions if skb->len < mtu	2018-10-17 21:51:13 -07:00
dst_cache.h	…
dst_metadata.h	…
dst_ops.h	…
erspan.h	…
esp.h	…
ethoc.h	…
failover.h	…
fib_notifier.h	…
fib_rules.h	…
firewire.h	…
flow.h	net: reorder flowi_common fields to avoid holes	2018-11-30 17:12:39 -08:00
flow_dissector.h	net/flow_dissector: correct comments on enum flow_dissector_key_id	2018-11-30 13:21:52 -08:00
fou.h	…
fq.h	…
fq_impl.h	…
garp.h	…
gen_stats.h	net: align gnet_stats_basic_cpu struct	2018-11-17 21:37:29 -08:00
genetlink.h	…
geneve.h	net: add netif_is_geneve()	2018-11-07 23:00:23 -08:00
gre.h	net: Add netif_is_gretap()/netif_is_ip6gretap()	2018-12-10 15:53:04 -08:00
gro_cells.h	…
gtp.h	…
gue.h	…
hwbm.h	…
icmp.h	net: Convert protocol error handlers from void to int	2018-11-08 17:13:08 -08:00
ieee80211_radiotap.h	…
ieee802154_netdev.h	…
if_inet6.h	net/ipv6: Add anycast addresses to a global hashtable	2018-11-02 23:54:56 -07:00
ife.h	…
ila.h	…
inet6_connection_sock.h	…
inet6_hashtables.h	net: allow binding socket in a VRF when there's an unbound socket	2018-11-07 16:12:38 -08:00
inet_common.h	net: use indirect call wrappers at GRO transport layer	2018-12-15 13:23:02 -08:00
inet_connection_sock.h	…
inet_ecn.h	inet: Refactor INET_ECN_decapsulate()	2018-10-17 17:45:07 -07:00
inet_frag.h	…
inet_hashtables.h	net: dccp: fix kernel crash on module load	2018-12-24 15:27:56 -08:00
inet_sock.h	net: ensure unbound stream socket to be chosen when not in a VRF	2018-11-07 16:12:38 -08:00
inet_timewait_sock.h	…
inetpeer.h	…
ip.h	ip: factor out protocol delivery helper	2018-11-07 16:23:05 -08:00
ip6_checksum.h	…
ip6_fib.h	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2018-10-19 11:03:06 -07:00
ip6_route.h	net: Add struct for fib dump filter	2018-10-16 00:13:12 -07:00
ip6_tunnel.h	udp: Support for error handlers of tunnels with arbitrary destination port	2018-11-08 17:13:08 -08:00
ip_fib.h	net: ipv4: Fix memory leak in network namespace dismantle	2019-01-15 13:33:44 -08:00
ip_tunnels.h	ip: validate header length on virtual device xmit	2019-01-01 12:05:02 -08:00
ip_vs.h	…
ipcomp.h	…
ipconfig.h	…
ipv6.h	ipv6: factor out protocol delivery helper	2018-11-07 16:23:05 -08:00
ipv6_frag.h	…
ipx.h	…
iw_handler.h	…
kcm.h	…
l3mdev.h	l3mdev: add function to retreive upper master	2018-12-03 14:15:26 -08:00
lag.h	…
lapb.h	…
lib80211.h	…
llc.h	…
llc_c_ac.h	…
llc_c_ev.h	…
llc_c_st.h	…
llc_conn.h	…
llc_if.h	…
llc_pdu.h	…
llc_s_ac.h	…
llc_s_ev.h	…
llc_s_st.h	…
llc_sap.h	…
lwtunnel.h	…
mac80211.h	mac80211: propagate the support for TWT to the driver	2018-12-18 14:18:49 +01:00
mac802154.h	…
mip6.h	…
mld.h	…
mpls.h	…
mpls_iptunnel.h	…
mrp.h	…
ncsi.h	…
ndisc.h	…
neighbour.h	neighbour: register rtnl doit handler	2018-12-19 13:37:34 -08:00
net_failover.h	…
net_namespace.h	…
net_ratelimit.h	…
netevent.h	…
netlabel.h	…
netlink.h	…
netprio_cgroup.h	…
netrom.h	…
nexthop.h	…
nl802154.h	…
nsh.h	…
p8022.h	…
page_pool.h	…
ping.h	…
pkt_cls.h	net_sched: fold tcf_block_cb_call() into tc_setup_cb_call()	2018-12-14 15:32:19 -08:00
pkt_sched.h	…
pptp.h	…
protocol.h	net: Convert protocol error handlers from void to int	2018-11-08 17:13:08 -08:00
psample.h	…
psnap.h	…
raw.h	net: fix raw socket lookup device bind matching with VRFs	2018-11-07 16:12:39 -08:00
rawv6.h	…
red.h	…
regulatory.h	…
request_sock.h	…
rose.h	…
route.h	…
rsi_91x.h	…
rtnetlink.h	net: Add extack argument to rtnl_create_link	2018-11-06 15:00:45 -08:00
sch_generic.h	net: sched: register callbacks for indirect tc block binds	2018-11-11 09:54:52 -08:00
scm.h	…
secure_seq.h	…
seg6.h	net: seg6.h: remove an unused #include	2018-12-20 16:56:04 -08:00
seg6_hmac.h	…
seg6_local.h	…
slhc_vj.h	…
smc.h	…
snmp.h	…
sock.h	sock: Make sock->sk_stamp thread-safe	2019-01-01 09:47:59 -08:00
sock_reuseport.h	…
stp.h	…
strparser.h	…
switchdev.h	net: switchdev: Add extack to switchdev_handle_port_obj_add() callback	2018-12-12 16:34:22 -08:00
tcp.h	tcp: reduce POLLOUT events caused by TCP_NOTSENT_LOWAT	2018-12-04 21:21:18 -08:00
tcp_states.h	…
timewait_sock.h	…
tipc.h	…
tls.h	Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next	2018-12-20 17:31:36 -08:00
transp_v6.h	…
tso.h	…
tun_proto.h	…
udp.h	net: Convert protocol error handlers from void to int	2018-11-08 17:13:08 -08:00
udp_tunnel.h	udp_tunnel: add config option to bind to a device	2018-12-03 14:15:26 -08:00
udplite.h	…
vsock_addr.h	…
vxlan.h	vxlan: Add vxlan_fdb_clear_offload()	2018-12-07 12:59:08 -08:00
wext.h	…
wimax.h	…
x25.h	…
x25device.h	…
xdp.h	…
xdp_sock.h	…
xfrm.h	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2018-12-20 11:53:36 -08:00