android_kernel_motorola_sm6225/net/ipv6
Eric Dumazet 12d94a8049 ipv6: fix NULL dereference in ip6_route_dev_notify()
Based on a syzkaller report [1], I found that a per cpu allocation
failure in snmp6_alloc_dev() would then lead to NULL dereference in
ip6_route_dev_notify().

It seems this is a very old bug, thus no Fixes tag in this submission.

Let's add in6_dev_put_clear() helper, as we will probably use
it elsewhere (once available/present in net-next)

[1]
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 17294 Comm: syz-executor6 Not tainted 4.13.0-rc2+ #10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88019f456680 task.stack: ffff8801c6e58000
RIP: 0010:__read_once_size include/linux/compiler.h:250 [inline]
RIP: 0010:atomic_read arch/x86/include/asm/atomic.h:26 [inline]
RIP: 0010:refcount_sub_and_test+0x7d/0x1b0 lib/refcount.c:178
RSP: 0018:ffff8801c6e5f1b0 EFLAGS: 00010202
RAX: 0000000000000037 RBX: dffffc0000000000 RCX: ffffc90005d25000
RDX: ffff8801c6e5f218 RSI: ffffffff82342bbf RDI: 0000000000000001
RBP: ffff8801c6e5f240 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff10038dcbe37
R13: 0000000000000006 R14: 0000000000000001 R15: 00000000000001b8
FS:  00007f21e0429700(0000) GS:ffff8801dc100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001ddbc22000 CR3: 00000001d632b000 CR4: 00000000001426e0
DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 refcount_dec_and_test+0x1a/0x20 lib/refcount.c:211
 in6_dev_put include/net/addrconf.h:335 [inline]
 ip6_route_dev_notify+0x1c9/0x4a0 net/ipv6/route.c:3732
 notifier_call_chain+0x136/0x2c0 kernel/notifier.c:93
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
 call_netdevice_notifiers_info+0x51/0x90 net/core/dev.c:1678
 call_netdevice_notifiers net/core/dev.c:1694 [inline]
 rollback_registered_many+0x91c/0xe80 net/core/dev.c:7107
 rollback_registered+0x1be/0x3c0 net/core/dev.c:7149
 register_netdevice+0xbcd/0xee0 net/core/dev.c:7587
 register_netdev+0x1a/0x30 net/core/dev.c:7669
 loopback_net_init+0x76/0x160 drivers/net/loopback.c:214
 ops_init+0x10a/0x570 net/core/net_namespace.c:118
 setup_net+0x313/0x710 net/core/net_namespace.c:294
 copy_net_ns+0x27c/0x580 net/core/net_namespace.c:418
 create_new_namespaces+0x425/0x880 kernel/nsproxy.c:107
 unshare_nsproxy_namespaces+0xae/0x1e0 kernel/nsproxy.c:206
 SYSC_unshare kernel/fork.c:2347 [inline]
 SyS_unshare+0x653/0xfa0 kernel/fork.c:2297
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x4512c9
RSP: 002b:00007f21e0428c08 EFLAGS: 00000216 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 0000000000718150 RCX: 00000000004512c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000062020200
RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000216 R12: 00000000004b973d
R13: 00000000ffffffff R14: 000000002001d000 R15: 00000000000002dd
Code: 50 2b 34 82 c7 00 f1 f1 f1 f1 c7 40 04 04 f2 f2 f2 c7 40 08 f3 f3
f3 f3 e8 a1 43 39 ff 4c 89 f8 48 8b 95 70 ff ff ff 48 c1 e8 03 <0f> b6
0c 18 4c 89 f8 83 e0 07 83 c0 03 38 c8 7c 08 84 c9 0f 85
RIP: __read_once_size include/linux/compiler.h:250 [inline] RSP:
ffff8801c6e5f1b0
RIP: atomic_read arch/x86/include/asm/atomic.h:26 [inline] RSP:
ffff8801c6e5f1b0
RIP: refcount_sub_and_test+0x7d/0x1b0 lib/refcount.c:178 RSP:
ffff8801c6e5f1b0
---[ end trace e441d046c6410d31 ]---

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-15 17:06:34 -07:00
..
ila Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-06-15 11:59:32 -04:00
netfilter Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next 2017-06-30 06:27:09 -07:00
addrconf.c net, ipv6: convert inet6_ifaddr.refcnt from atomic_t to refcount_t 2017-07-04 01:29:04 -07:00
addrconf_core.c Ipvlan should return an error when an address is already in use. 2017-06-09 12:26:07 -04:00
addrlabel.c net, ipv6: convert ip6addrlbl_entry.refcnt from atomic_t to refcount_t 2017-07-04 01:29:04 -07:00
af_inet6.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-04-26 22:39:08 -04:00
ah6.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2017-06-23 14:17:31 -04:00
anycast.c net, ipv6: convert ifacaddr6.aca_refcnt from atomic_t to refcount_t 2017-07-04 01:29:04 -07:00
calipso.c net, calipso: convert calipso_doi.refcount from atomic_t to refcount_t 2017-07-04 22:35:16 +01:00
datagram.c net: convert sock.sk_refcnt from atomic_t to refcount_t 2017-07-01 07:39:08 -07:00
esp6.c net: convert sock.sk_wmem_alloc from atomic_t to refcount_t 2017-07-01 07:39:08 -07:00
esp6_offload.c esp6_offload: Fix IP6CB(skb)->nhoff for ESP GRO 2017-06-22 10:49:14 +02:00
exthdrs.c udp6: fix jumbogram reception 2017-07-31 22:01:21 -07:00
exthdrs_core.c ipv6: constify the skb pointer of ipv6_find_tlv(). 2016-06-27 15:06:15 -04:00
exthdrs_offload.c
fib6_rules.c ipv6: Do not leak throw route references 2017-06-20 15:34:02 -04:00
fou6.c fou: make local function static 2017-05-21 13:42:36 -04:00
icmp.c net: don't global ICMP rate limit packets originating from loopback 2017-06-14 15:33:58 -04:00
inet6_connection_sock.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-01-28 10:33:06 -05:00
inet6_hashtables.c net: convert sock.sk_refcnt from atomic_t to refcount_t 2017-07-01 07:39:08 -07:00
ip6_checksum.c ipv6: fix checksum annotation in udp6_csum_init 2016-06-14 15:26:42 -04:00
ip6_fib.c net: ipv6: Compare lwstate in detecting duplicate nexthops 2017-07-06 10:48:01 +01:00
ip6_flowlabel.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
ip6_gre.c net: add netlink_ext_ack argument to rtnl_link_ops.validate 2017-06-26 23:13:22 -04:00
ip6_icmp.c ipv6: icmp: add a force_saddr param to icmp6_send() 2016-06-18 22:11:38 -07:00
ip6_input.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-04-20 10:35:33 -04:00
ip6_offload.c ipv6: Fix leak in ipv6_gso_segment(). 2017-06-04 21:41:10 -04:00
ip6_offload.h udp: Add GRO functions to UDP socket 2016-04-07 16:53:29 -04:00
ip6_output.c udp: consistently apply ufo or fragmentation 2017-08-10 09:52:12 -07:00
ip6_tunnel.c net: add netlink_ext_ack argument to rtnl_link_ops.validate 2017-06-26 23:13:22 -04:00
ip6_udp_tunnel.c ip6_udp_tunnel: remove unused IPCB related codes 2016-11-02 15:18:36 -04:00
ip6_vti.c net: add netlink_ext_ack argument to rtnl_link_ops.validate 2017-06-26 23:13:22 -04:00
ip6mr.c ip6mr: add netlink notifications on mrt6msg cache reports 2017-06-21 11:22:53 -04:00
ipcomp6.c net: inet: Support UID-based routing in IP protocols. 2016-11-04 14:45:23 -04:00
ipv6_sockglue.c Merge branch 'work.memdup_user' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-07-05 16:05:24 -07:00
Kconfig ipv6: sr: select DST_CACHE by default 2017-03-27 16:05:06 -07:00
Makefile esp: Add a software GRO codepath 2017-02-15 11:04:11 +01:00
mcast.c net, ipv6: convert ifmcaddr6.mca_refcnt from atomic_t to refcount_t 2017-07-04 01:29:04 -07:00
mcast_snoop.c
mip6.c ktime: Get rid of ktime_equal() 2016-12-25 17:21:23 +01:00
ndisc.c networking: make skb_put & friends return void pointers 2017-06-16 11:48:39 -04:00
netfilter.c net: inet: Support UID-based routing in IP protocols. 2016-11-04 14:45:23 -04:00
output_core.c ipv6: avoid overflow of offset in ip6_find_1stfragopt 2017-07-19 22:50:14 -07:00
ping.c net: ping: do not abuse udp_poll() 2017-06-04 22:56:55 -04:00
proc.c proc: snmp6: Use correct type in memset 2017-06-12 09:53:14 -04:00
protocol.c net: Add sysctl to toggle early demux for tcp and udp 2017-03-24 13:17:07 -07:00
raw.c net: ping: do not abuse udp_poll() 2017-06-04 22:56:55 -04:00
reassembly.c ipv6: on reassembly, record frag_max_size 2016-11-03 15:41:11 -04:00
route.c ipv6: fix NULL dereference in ip6_route_dev_notify() 2017-08-15 17:06:34 -07:00
seg6.c ipv6: drop unused variables in seg6_genl_dumphac 2017-05-21 13:42:36 -04:00
seg6_hmac.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-02-07 16:29:30 -05:00
seg6_iptunnel.c net: add extack arg to lwtunnel build state 2017-05-30 11:55:32 -04:00
sit.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-06-30 12:43:08 -04:00
syncookies.c ipv4: ipv6: initialize treq->txhash in cookie_v[46]_check() 2017-07-18 11:22:51 -07:00
sysctl_net_ipv6.c calipso: Add a label cache. 2016-06-27 15:06:17 -04:00
tcp_ipv6.c tcp: fix possible deadlock in TCP stack vs BPF filter 2017-08-14 22:31:27 -07:00
tcpv6_offload.c
tunnel6.c ipv6: fix tunnel error handling 2015-11-03 10:52:13 -05:00
udp.c udp6: fix jumbogram reception 2017-07-31 22:01:21 -07:00
udp_impl.h udp: make *udp*_queue_rcv_skb() functions static 2017-05-18 10:23:33 -04:00
udp_offload.c net: avoid skb_warn_bad_offload false positives on UFO 2017-08-08 21:39:01 -07:00
udplite.c udplite: call proper backlog handlers 2016-11-24 15:32:14 -05:00
xfrm6_input.c xfrm6: Fix IPv6 payload_len in xfrm6_transport_finish 2017-06-22 10:49:14 +02:00
xfrm6_mode_beet.c networking: make skb_pull & friends return void pointers 2017-06-16 11:48:39 -04:00
xfrm6_mode_ro.c ipv6: xfrm: Handle errors reported by xfrm6_find_1stfragopt() 2017-06-02 13:57:27 -04:00
xfrm6_mode_transport.c ipv6: xfrm: Handle errors reported by xfrm6_find_1stfragopt() 2017-06-02 13:57:27 -04:00
xfrm6_mode_tunnel.c xfrm: Add encapsulation header offsets while SKB is not encrypted 2017-04-14 10:07:39 +02:00
xfrm6_output.c xfrm: Add an IPsec hardware offloading API 2017-04-14 10:06:10 +02:00
xfrm6_policy.c xfrm: policy: make policy backend const 2017-02-09 10:22:19 +01:00
xfrm6_protocol.c xfrm: input: constify xfrm_input_afinfo 2017-02-09 10:22:17 +01:00
xfrm6_state.c
xfrm6_tunnel.c net, ipv6: convert xfrm6_tunnel_spi.refcnt from atomic_t to refcount_t 2017-07-04 01:29:04 -07:00