BUG: please report to dccp@xxxxxxxxxxxxxxx => prev = 5, last = 5 at net/dccp/ccids/lib/packet_history.c:LINE/tfrc_rx_his

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    771b65e89c8a Add linux-next specific files for 20181011
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=167d2376400000
kernel config:  https://syzkaller.appspot.com/x/.config?x=45f1c06c4da0a925
dashboard link: https://syzkaller.appspot.com/bug?extid=e326127852f785c44347
compiler:       gcc (GCC) 8.0.1 20180413 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+e326127852f785c44347@xxxxxxxxxxxxxxxxxxxxxxxxx

BUG: please report to dccp@xxxxxxxxxxxxxxx => prev = 5, last = 5 at  
net/dccp/ccids/lib/packet_history.c:425/tfrc_rx_hist_sample_rtt()
CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 4.19.0-rc7-next-20181011+ #92
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+0x244/0x3ab lib/dump_stack.c:113
 tfrc_rx_hist_sample_rtt.cold.3+0x54/0x5c  
net/dccp/ccids/lib/packet_history.c:422
 ccid3_hc_rx_packet_recv+0x5c4/0xeb0 net/dccp/ccids/ccid3.c:767
 ccid_hc_rx_packet_recv net/dccp/ccid.h:185 [inline]
 dccp_deliver_input_to_ccids+0xf0/0x280 net/dccp/input.c:180
 dccp_rcv_established+0x87/0xb0 net/dccp/input.c:378
 dccp_v4_do_rcv+0x153/0x180 net/dccp/ipv4.c:656
 sk_backlog_rcv include/net/sock.h:932 [inline]
 __sk_receive_skb+0x3e0/0xeb0 net/core/sock.c:473
binder: send failed reply for transaction 41 to 27388:27389
 dccp_v4_rcv+0x10f9/0x1f58 net/dccp/ipv4.c:877
 ip_local_deliver_finish+0x2e9/0xda0 net/ipv4/ip_input.c:215
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ip_local_deliver+0x1e4/0x740 net/ipv4/ip_input.c:256
 dst_input include/net/dst.h:450 [inline]
 ip_rcv_finish+0x1f9/0x300 net/ipv4/ip_input.c:415
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ip_rcv+0xe8/0x600 net/ipv4/ip_input.c:524
 __netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4908
 __netif_receive_skb+0x27/0x1e0 net/core/dev.c:5018
 process_backlog+0x24e/0x7a0 net/core/dev.c:5822
 napi_poll net/core/dev.c:6242 [inline]
 net_rx_action+0x7fa/0x19b0 net/core/dev.c:6308
 __do_softirq+0x30d/0xb26 kernel/softirq.c:292
 run_ksoftirqd+0x5e/0x100 kernel/softirq.c:654
 smpboot_thread_fn+0x68b/0xa00 kernel/smpboot.c:164
 kthread+0x35a/0x440 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
dccp_close: ABORT with 52224 bytes unread
binder: send failed reply for transaction 43 to 27399:27404
dccp_close: ABORT with 3584 bytes unread
binder: send failed reply for transaction 45 to 27417:27418
binder: send failed reply for transaction 47 to 27424:27425
dccp_close: ABORT with 105984 bytes unread
dccp_close: ABORT with 105984 bytes unread
dccp_close: ABORT with 105984 bytes unread
nf_conntrack: default automatic helper assignment has been turned off for  
security reasons and CT-based  firewall rule not found. Use the iptables CT  
target to attach helpers instead.
Dead loop on virtual device ip6_vti0, fix it urgently!
Dead loop on virtual device ip6_vti0, fix it urgently!
Dead loop on virtual device ip6_vti0, fix it urgently!
Dead loop on virtual device ip6_vti0, fix it urgently!
Dead loop on virtual device ip6_vti0, fix it urgently!
Dead loop on virtual device ip6_vti0, fix it urgently!
IPVS: sync thread started: state = BACKUP, mcast_ifn = team_slave_0, syncid  
= 0, id = 0
Dead loop on virtual device ip6_vti0, fix it urgently!
IPVS: sync thread started: state = BACKUP, mcast_ifn = team_slave_0, syncid  
= 0, id = 0
IPVS: ftp: loaded support on port[0] = 21

: renamed from bpq0
IPVS: ftp: loaded support on port[0] = 21


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