linux_dsm_epyc7002/include/net
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
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_impl.h
codel_qdisc.h
codel.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_dev.h
dn_fib.h
dn_neigh.h
dn_nsp.h
dn_route.h
dn.h
dsa.h net: dsa: ksz: Rename NET_DSA_TAG_KSZ to _KSZ9477 2018-12-16 14:23:33 -08:00
dsfield.h
dst_cache.h
dst_metadata.h
dst_ops.h
dst.h geneve, vxlan: Don't set exceptions if skb->len < mtu 2018-10-17 21:51:13 -07:00
erspan.h
esp.h
ethoc.h
failover.h
fib_notifier.h
fib_rules.h
firewire.h
flow_dissector.h net/flow_dissector: correct comments on enum flow_dissector_key_id 2018-11-30 13:21:52 -08:00
flow.h net: reorder flowi_common fields to avoid holes 2018-11-30 17:12:39 -08:00
fou.h
fq_impl.h
fq.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
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
ip.h ip: factor out protocol delivery helper 2018-11-07 16:23:05 -08:00
ipcomp.h
ipconfig.h
ipv6_frag.h
ipv6.h ipv6: factor out protocol delivery helper 2018-11-07 16:23:05 -08:00
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_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
llc.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_iptunnel.h
mpls.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_hmac.h
seg6_local.h
seg6.h net: seg6.h: remove an unused #include 2018-12-20 16:56:04 -08:00
slhc_vj.h
smc.h
snmp.h
sock_reuseport.h
sock.h sock: Make sock->sk_stamp thread-safe 2019-01-01 09:47:59 -08:00
Space.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_states.h
tcp.h tcp: reduce POLLOUT events caused by TCP_NOTSENT_LOWAT 2018-12-04 21:21:18 -08:00
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_tunnel.h udp_tunnel: add config option to bind to a device 2018-12-03 14:15:26 -08:00
udp.h net: Convert protocol error handlers from void to int 2018-11-08 17:13:08 -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_sock.h
xdp.h
xfrm.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-12-20 11:53:36 -08:00