linux/net
Eric Dumazet 8b485ce698 tcp: do not inherit fastopen_req from parent
Under fuzzer stress, it is possible that a child gets a non NULL
fastopen_req pointer from its parent at accept() time, when/if parent
morphs from listener to active session.

We need to make sure this can not happen, by clearing the field after
socket cloning.

BUG: Double free or freeing an invalid pointer
Unexpected shadow byte: 0xFB
CPU: 3 PID: 20933 Comm: syz-executor3 Not tainted 4.11.0+ #306
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs
01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x292/0x395 lib/dump_stack.c:52
 kasan_object_err+0x1c/0x70 mm/kasan/report.c:164
 kasan_report_double_free+0x5c/0x70 mm/kasan/report.c:185
 kasan_slab_free+0x9d/0xc0 mm/kasan/kasan.c:580
 slab_free_hook mm/slub.c:1357 [inline]
 slab_free_freelist_hook mm/slub.c:1379 [inline]
 slab_free mm/slub.c:2961 [inline]
 kfree+0xe8/0x2b0 mm/slub.c:3882
 tcp_free_fastopen_req net/ipv4/tcp.c:1077 [inline]
 tcp_disconnect+0xc15/0x13e0 net/ipv4/tcp.c:2328
 inet_child_forget+0xb8/0x600 net/ipv4/inet_connection_sock.c:898
 inet_csk_reqsk_queue_add+0x1e7/0x250
net/ipv4/inet_connection_sock.c:928
 tcp_get_cookie_sock+0x21a/0x510 net/ipv4/syncookies.c:217
 cookie_v4_check+0x1a19/0x28b0 net/ipv4/syncookies.c:384
 tcp_v4_cookie_check net/ipv4/tcp_ipv4.c:1384 [inline]
 tcp_v4_do_rcv+0x731/0x940 net/ipv4/tcp_ipv4.c:1421
 tcp_v4_rcv+0x2dc0/0x31c0 net/ipv4/tcp_ipv4.c:1715
 ip_local_deliver_finish+0x4cc/0xc20 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:257 [inline]
 ip_local_deliver+0x1ce/0x700 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:492 [inline]
 ip_rcv_finish+0xb1d/0x20b0 net/ipv4/ip_input.c:396
 NF_HOOK include/linux/netfilter.h:257 [inline]
 ip_rcv+0xd8c/0x19c0 net/ipv4/ip_input.c:487
 __netif_receive_skb_core+0x1ad1/0x3400 net/core/dev.c:4210
 __netif_receive_skb+0x2a/0x1a0 net/core/dev.c:4248
 process_backlog+0xe5/0x6c0 net/core/dev.c:4868
 napi_poll net/core/dev.c:5270 [inline]
 net_rx_action+0xe70/0x18e0 net/core/dev.c:5335
 __do_softirq+0x2fb/0xb99 kernel/softirq.c:284
 do_softirq_own_stack+0x1c/0x30 arch/x86/entry/entry_64.S:899
 </IRQ>
 do_softirq.part.17+0x1e8/0x230 kernel/softirq.c:328
 do_softirq kernel/softirq.c:176 [inline]
 __local_bh_enable_ip+0x1cf/0x1e0 kernel/softirq.c:181
 local_bh_enable include/linux/bottom_half.h:31 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:931 [inline]
 ip_finish_output2+0x9ab/0x15e0 net/ipv4/ip_output.c:230
 ip_finish_output+0xa35/0xdf0 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:246 [inline]
 ip_output+0x1f6/0x7b0 net/ipv4/ip_output.c:404
 dst_output include/net/dst.h:486 [inline]
 ip_local_out+0x95/0x160 net/ipv4/ip_output.c:124
 ip_queue_xmit+0x9a8/0x1a10 net/ipv4/ip_output.c:503
 tcp_transmit_skb+0x1ade/0x3470 net/ipv4/tcp_output.c:1057
 tcp_write_xmit+0x79e/0x55b0 net/ipv4/tcp_output.c:2265
 __tcp_push_pending_frames+0xfa/0x3a0 net/ipv4/tcp_output.c:2450
 tcp_push+0x4ee/0x780 net/ipv4/tcp.c:683
 tcp_sendmsg+0x128d/0x39b0 net/ipv4/tcp.c:1342
 inet_sendmsg+0x164/0x5b0 net/ipv4/af_inet.c:762
 sock_sendmsg_nosec net/socket.c:633 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:643
 SYSC_sendto+0x660/0x810 net/socket.c:1696
 SyS_sendto+0x40/0x50 net/socket.c:1664
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x446059
RSP: 002b:00007faa6761fb58 EFLAGS: 00000282 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000017 RCX: 0000000000446059
RDX: 0000000000000001 RSI: 0000000020ba3fcd RDI: 0000000000000017
RBP: 00000000006e40a0 R08: 0000000020ba4ff0 R09: 0000000000000010
R10: 0000000020000000 R11: 0000000000000282 R12: 0000000000708150
R13: 0000000000000000 R14: 00007faa676209c0 R15: 00007faa67620700
Object at ffff88003b5bbcb8, in cache kmalloc-64 size: 64
Allocated:
PID = 20909
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x43/0xd0 mm/kasan/kasan.c:513
 set_track mm/kasan/kasan.c:525 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:616
 kmem_cache_alloc_trace+0x82/0x270 mm/slub.c:2745
 kmalloc include/linux/slab.h:490 [inline]
 kzalloc include/linux/slab.h:663 [inline]
 tcp_sendmsg_fastopen net/ipv4/tcp.c:1094 [inline]
 tcp_sendmsg+0x221a/0x39b0 net/ipv4/tcp.c:1139
 inet_sendmsg+0x164/0x5b0 net/ipv4/af_inet.c:762
 sock_sendmsg_nosec net/socket.c:633 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:643
 SYSC_sendto+0x660/0x810 net/socket.c:1696
 SyS_sendto+0x40/0x50 net/socket.c:1664
 entry_SYSCALL_64_fastpath+0x1f/0xbe
Freed:
PID = 20909
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x43/0xd0 mm/kasan/kasan.c:513
 set_track mm/kasan/kasan.c:525 [inline]
 kasan_slab_free+0x73/0xc0 mm/kasan/kasan.c:589
 slab_free_hook mm/slub.c:1357 [inline]
 slab_free_freelist_hook mm/slub.c:1379 [inline]
 slab_free mm/slub.c:2961 [inline]
 kfree+0xe8/0x2b0 mm/slub.c:3882
 tcp_free_fastopen_req net/ipv4/tcp.c:1077 [inline]
 tcp_disconnect+0xc15/0x13e0 net/ipv4/tcp.c:2328
 __inet_stream_connect+0x20c/0xf90 net/ipv4/af_inet.c:593
 tcp_sendmsg_fastopen net/ipv4/tcp.c:1111 [inline]
 tcp_sendmsg+0x23a8/0x39b0 net/ipv4/tcp.c:1139
 inet_sendmsg+0x164/0x5b0 net/ipv4/af_inet.c:762
 sock_sendmsg_nosec net/socket.c:633 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:643
 SYSC_sendto+0x660/0x810 net/socket.c:1696
 SyS_sendto+0x40/0x50 net/socket.c:1664
 entry_SYSCALL_64_fastpath+0x1f/0xbe

Fixes: e994b2f0fb ("tcp: do not lock listener to process SYN packets")
Fixes: 7db92362d2 ("tcp: fix potential double free issue for fastopen_req")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Wei Wang <weiwan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-04 11:00:04 -04:00
..
6lowpan 6lowpan: Don't set IFF_NO_QUEUE 2017-04-12 22:02:40 +02:00
9p net/9p: switch to copy_from_iter_full() 2017-04-21 13:57:22 -04:00
802
8021q netlink: pass extended ACK struct to parsing functions 2017-04-13 13:58:22 -04:00
appletalk lib/vsprintf.c: remove %Z support 2017-02-27 18:43:47 -08:00
atm neighbour: fix nlmsg_pid in notifications 2017-03-22 10:48:49 -07:00
ax25 net: Work around lockdep limitation in sockets that use sockets 2017-03-09 18:23:27 -08:00
batman-adv This feature/cleanup patchset includes the following patches: 2017-04-06 14:37:50 -07:00
bluetooth Bluetooth: Add selftest for ECDH key generation 2017-04-30 16:52:43 +03:00
bpf bpf: Align packet data properly in program testing framework. 2017-05-02 11:46:28 -04:00
bridge Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2017-05-03 10:11:26 -04:00
caif sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h> 2017-03-02 08:42:29 +01:00
can can: fix CAN BCM build with CONFIG_PROC_FS disabled 2017-04-27 09:34:13 +02:00
ceph libceph: force GFP_NOIO for socket allocations 2017-03-23 12:03:36 +01:00
core Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-05-02 16:40:27 -07:00
dcb net: rtnetlink: plumb extended ack to doit function 2017-04-17 15:35:38 -04:00
dccp dccp: fix memory leak during tear-down of unsuccessful connection request 2017-03-13 22:00:42 -07:00
decnet Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next 2017-05-01 10:47:53 -04:00
dns_resolver Merge branch 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-03-03 10:16:38 -08:00
dsa net: dsa: Remove redundant NULL dst check 2017-04-21 10:41:24 -04:00
ethernet Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2017-02-16 21:25:49 -05:00
hsr netlink: extended ACK reporting 2017-04-13 13:58:20 -04:00
ieee802154 netlink: pass extended ACK struct where available 2017-04-13 13:58:22 -04:00
ife net: Introduce ife encapsulation module 2017-02-03 15:16:45 -05:00
ipv4 tcp: do not inherit fastopen_req from parent 2017-05-04 11:00:04 -04:00
ipv6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2017-05-03 10:11:26 -04:00
ipx ipx: call ipxitf_put() in ioctl error path 2017-05-02 15:34:53 -04:00
irda net: Work around lockdep limitation in sockets that use sockets 2017-03-09 18:23:27 -08:00
iucv net: Work around lockdep limitation in sockets that use sockets 2017-03-09 18:23:27 -08:00
kcm kcm: remove a useless copy_from_user() 2017-04-17 13:28:48 -04:00
key Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-04-21 20:23:53 -07:00
l2tp l2tp: remove useless device duplication test in l2tp_eth_create() 2017-04-27 16:32:13 -04:00
l3mdev
lapb
llc net: Work around lockdep limitation in sockets that use sockets 2017-03-09 18:23:27 -08:00
mac80211 cfg80211: add request id to cfg80211_sched_scan_*() api 2017-04-28 14:51:43 +02:00
mac802154 drivers: add explicit interrupt.h includes 2017-03-30 11:05:34 -07:00
mpls net: rtnetlink: plumb extended ack to doit function 2017-04-17 15:35:38 -04:00
ncsi
netfilter Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2017-05-03 10:11:26 -04:00
netlabel netlink: pass extended ACK struct to parsing functions 2017-04-13 13:58:22 -04:00
netlink netlink: pass extended ACK struct where available 2017-04-13 13:58:22 -04:00
netrom net: Work around lockdep limitation in sockets that use sockets 2017-03-09 18:23:27 -08:00
nfc NFC 4.12 pull request 2017-04-21 15:29:40 -04:00
openvswitch Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2017-05-03 10:11:26 -04:00
packet Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-04-26 22:39:08 -04:00
phonet net: rtnetlink: plumb extended ack to doit function 2017-04-17 15:35:38 -04:00
psample
qrtr Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-04-21 20:23:53 -07:00
rds Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-05-02 16:40:27 -07:00
rfkill
rose net: Work around lockdep limitation in sockets that use sockets 2017-03-09 18:23:27 -08:00
rxrpc rxrpc: Trace client call connection 2017-04-06 11:10:41 +01:00
sched net: sched: add helpers to handle extended actions 2017-05-02 15:33:54 -04:00
sctp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-05-02 16:40:27 -07:00
smc net/smc: do not use IB_SEND_INLINE together with mapped data 2017-04-11 23:01:14 -04:00
strparser strparser: destroy workqueue on module exit 2017-03-03 20:43:26 -08:00
sunrpc The restriction of NFSv4 to TCP went overboard and also broke the 2017-04-01 10:43:37 -07:00
switchdev netlink: pass extended ACK struct to parsing functions 2017-04-13 13:58:22 -04:00
tipc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-05-02 16:40:27 -07:00
unix af_unix: Use designated initializers 2017-04-06 12:43:04 -07:00
vmw_vsock VSOCK: Add virtio vsock vsockmon hooks 2017-04-24 12:35:56 -04:00
wimax
wireless cfg80211: add request id to cfg80211_sched_scan_*() api 2017-04-28 14:51:43 +02:00
x25 net: Work around lockdep limitation in sockets that use sockets 2017-03-09 18:23:27 -08:00
xfrm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-05-02 16:40:27 -07:00
compat.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-02-22 10:15:09 -08:00
Kconfig bpf: make jited programs visible in traces 2017-02-17 13:40:05 -05:00
Makefile bpf: introduce BPF_PROG_TEST_RUN command 2017-04-01 12:45:57 -07:00
socket.c l2tp: device MTU setup, tunnel socket needs a lock 2017-04-17 13:01:48 -04:00
sysctl_net.c