Re: BUG: please report to d...@vger.kernel.org => prev = 0, last = 0 at net/dccp/ccids/lib/packet_history.c:LINE/tfrc_rx_his

2018-05-08 Thread Eric Biggers 
On Wed, May 09, 2018 at 07:23:41AM +0200, 'Dmitry Vyukov' via syzkaller-bugs 
wrote:
> On Wed, May 9, 2018 at 7:05 AM, Eric Biggers  wrote:
> > On Sat, May 05, 2018 at 05:57:02PM -0700, syzbot wrote:
> >> Hello,
> >>
> >> syzbot found the following crash on:
> >>
> >> HEAD commit:c1c07416cdd4 Merge tag 'kbuild-fixes-v4.17' of 
> >> git://git.k..
> >> git tree:   upstream
> >> console output: https://syzkaller.appspot.com/x/log.txt?x=13d5de4780
> >> kernel config:  https://syzkaller.appspot.com/x/.config?x=5a1dc06635c10d27
> >> dashboard link: 
> >> https://syzkaller.appspot.com/bug?extid=99858724c0ba555a12ea
> >> compiler:   gcc (GCC) 8.0.1 20180413 (experimental)
> >> syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=170afde780
> >> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=141b4be780
> >>
> >> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> >> Reported-by: syzbot+99858724c0ba555a1...@syzkaller.appspotmail.com
> >>
> >> random: sshd: uninitialized urandom read (32 bytes read)
> >> random: sshd: uninitialized urandom read (32 bytes read)
> >> random: sshd: uninitialized urandom read (32 bytes read)
> >> random: sshd: uninitialized urandom read (32 bytes read)
> >> BUG: please report to d...@vger.kernel.org => prev = 0, last = 0 at
> >> net/dccp/ccids/lib/packet_history.c:425/tfrc_rx_hist_sample_rtt()
> >> CPU: 0 PID: 4495 Comm: syz-executor551 Not tainted 4.17.0-rc3+ #34
> >> 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+0x1b9/0x294 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+0x5c8/0xed0 net/dccp/ccids/ccid3.c:765
> >>  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:654
> >>  sk_backlog_rcv include/net/sock.h:909 [inline]
> >>  __sk_receive_skb+0x3a2/0xd60 net/core/sock.c:513
> >>  dccp_v4_rcv+0x10e5/0x1f3f net/dccp/ipv4.c:875
> >>  ip_local_deliver_finish+0x2e3/0xd80 net/ipv4/ip_input.c:215
> >>  NF_HOOK include/linux/netfilter.h:288 [inline]
> >>  ip_local_deliver+0x1e1/0x720 net/ipv4/ip_input.c:256
> >>  dst_input include/net/dst.h:450 [inline]
> >>  ip_rcv_finish+0x81b/0x2200 net/ipv4/ip_input.c:396
> >>  NF_HOOK include/linux/netfilter.h:288 [inline]
> >>  ip_rcv+0xb70/0x143d net/ipv4/ip_input.c:492
> >>  __netif_receive_skb_core+0x26f5/0x3630 net/core/dev.c:4592
> >>  __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:4657
> >>  process_backlog+0x219/0x760 net/core/dev.c:5337
> >>  napi_poll net/core/dev.c:5735 [inline]
> >>  net_rx_action+0x7b7/0x1930 net/core/dev.c:5801
> >>  __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285
> >>  do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1046
> >>  
> >>  do_softirq.part.17+0x14d/0x190 kernel/softirq.c:329
> >>  do_softirq arch/x86/include/asm/preempt.h:23 [inline]
> >>  __local_bh_enable_ip+0x1ec/0x230 kernel/softirq.c:182
> >>  local_bh_enable include/linux/bottom_half.h:32 [inline]
> >>  rcu_read_unlock_bh include/linux/rcupdate.h:728 [inline]
> >>  ip_finish_output2+0xab2/0x1840 net/ipv4/ip_output.c:231
> >>  ip_finish_output+0x828/0xf80 net/ipv4/ip_output.c:317
> >>  NF_HOOK_COND include/linux/netfilter.h:277 [inline]
> >>  ip_output+0x21b/0x850 net/ipv4/ip_output.c:405
> >>  dst_output include/net/dst.h:444 [inline]
> >>  ip_local_out+0xc5/0x1b0 net/ipv4/ip_output.c:124
> >>  ip_queue_xmit+0x9d7/0x1f70 net/ipv4/ip_output.c:504
> >>  dccp_transmit_skb+0x999/0x12e0 net/dccp/output.c:142
> >>  dccp_xmit_packet+0x250/0x790 net/dccp/output.c:281
> >>  dccp_write_xmit+0x190/0x1f0 net/dccp/output.c:363
> >>  dccp_sendmsg+0x8c7/0x1020 net/dccp/proto.c:818
> >>  inet_sendmsg+0x19f/0x690 net/ipv4/af_inet.c:798
> >>  sock_sendmsg_nosec net/socket.c:629 [inline]
> >>  sock_sendmsg+0xd5/0x120 net/socket.c:639
> >>  ___sys_sendmsg+0x525/0x940 net/socket.c:2117
> >>  __sys_sendmmsg+0x240/0x6f0 net/socket.c:2212
> >>  __do_sys_sendmmsg net/socket.c:2241 [inline]
> >>  __se_sys_sendmmsg net/socket.c:2238 [inline]
> >>  __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2238
> >>  do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
> >>  entry_SYSCALL_64_after_hwframe+0x49/0xbe
> >> RIP: 0033:0x445d09
> >> RSP: 002b:7f3c7eff5d88 EFLAGS: 0293 ORIG_RAX: 0133
> >> RAX: ffda RBX: 006dac40 RCX: 00445d09
> >> RDX: 0001 RSI: 00
> >>
> >>
> >> ---
> >> This bug is generated by a bot. It may contain errors.
> >> See https://goo.gl/tpsmEJ for more information about syzbot.
> >> syzbot engineers can be reached at syzkal...@googlegroups.com.
> >>
> >> syzbot will keep track of this bug report.
> >> If you forgot to add

Re: BUG: please report to d...@vger.kernel.org => prev = 0, last = 0 at net/dccp/ccids/lib/packet_history.c:LINE/tfrc_rx_his

2018-05-08 Thread Eric Biggers 
On Wed, May 09, 2018 at 07:23:41AM +0200, 'Dmitry Vyukov' via syzkaller-bugs 
wrote:
> On Wed, May 9, 2018 at 7:05 AM, Eric Biggers  wrote:
> > On Sat, May 05, 2018 at 05:57:02PM -0700, syzbot wrote:
> >> Hello,
> >>
> >> syzbot found the following crash on:
> >>
> >> HEAD commit:c1c07416cdd4 Merge tag 'kbuild-fixes-v4.17' of 
> >> git://git.k..
> >> git tree:   upstream
> >> console output: https://syzkaller.appspot.com/x/log.txt?x=13d5de4780
> >> kernel config:  https://syzkaller.appspot.com/x/.config?x=5a1dc06635c10d27
> >> dashboard link: 
> >> https://syzkaller.appspot.com/bug?extid=99858724c0ba555a12ea
> >> compiler:   gcc (GCC) 8.0.1 20180413 (experimental)
> >> syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=170afde780
> >> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=141b4be780
> >>
> >> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> >> Reported-by: syzbot+99858724c0ba555a1...@syzkaller.appspotmail.com
> >>
> >> random: sshd: uninitialized urandom read (32 bytes read)
> >> random: sshd: uninitialized urandom read (32 bytes read)
> >> random: sshd: uninitialized urandom read (32 bytes read)
> >> random: sshd: uninitialized urandom read (32 bytes read)
> >> BUG: please report to d...@vger.kernel.org => prev = 0, last = 0 at
> >> net/dccp/ccids/lib/packet_history.c:425/tfrc_rx_hist_sample_rtt()
> >> CPU: 0 PID: 4495 Comm: syz-executor551 Not tainted 4.17.0-rc3+ #34
> >> 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+0x1b9/0x294 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+0x5c8/0xed0 net/dccp/ccids/ccid3.c:765
> >>  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:654
> >>  sk_backlog_rcv include/net/sock.h:909 [inline]
> >>  __sk_receive_skb+0x3a2/0xd60 net/core/sock.c:513
> >>  dccp_v4_rcv+0x10e5/0x1f3f net/dccp/ipv4.c:875
> >>  ip_local_deliver_finish+0x2e3/0xd80 net/ipv4/ip_input.c:215
> >>  NF_HOOK include/linux/netfilter.h:288 [inline]
> >>  ip_local_deliver+0x1e1/0x720 net/ipv4/ip_input.c:256
> >>  dst_input include/net/dst.h:450 [inline]
> >>  ip_rcv_finish+0x81b/0x2200 net/ipv4/ip_input.c:396
> >>  NF_HOOK include/linux/netfilter.h:288 [inline]
> >>  ip_rcv+0xb70/0x143d net/ipv4/ip_input.c:492
> >>  __netif_receive_skb_core+0x26f5/0x3630 net/core/dev.c:4592
> >>  __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:4657
> >>  process_backlog+0x219/0x760 net/core/dev.c:5337
> >>  napi_poll net/core/dev.c:5735 [inline]
> >>  net_rx_action+0x7b7/0x1930 net/core/dev.c:5801
> >>  __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285
> >>  do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1046
> >>  
> >>  do_softirq.part.17+0x14d/0x190 kernel/softirq.c:329
> >>  do_softirq arch/x86/include/asm/preempt.h:23 [inline]
> >>  __local_bh_enable_ip+0x1ec/0x230 kernel/softirq.c:182
> >>  local_bh_enable include/linux/bottom_half.h:32 [inline]
> >>  rcu_read_unlock_bh include/linux/rcupdate.h:728 [inline]
> >>  ip_finish_output2+0xab2/0x1840 net/ipv4/ip_output.c:231
> >>  ip_finish_output+0x828/0xf80 net/ipv4/ip_output.c:317
> >>  NF_HOOK_COND include/linux/netfilter.h:277 [inline]
> >>  ip_output+0x21b/0x850 net/ipv4/ip_output.c:405
> >>  dst_output include/net/dst.h:444 [inline]
> >>  ip_local_out+0xc5/0x1b0 net/ipv4/ip_output.c:124
> >>  ip_queue_xmit+0x9d7/0x1f70 net/ipv4/ip_output.c:504
> >>  dccp_transmit_skb+0x999/0x12e0 net/dccp/output.c:142
> >>  dccp_xmit_packet+0x250/0x790 net/dccp/output.c:281
> >>  dccp_write_xmit+0x190/0x1f0 net/dccp/output.c:363
> >>  dccp_sendmsg+0x8c7/0x1020 net/dccp/proto.c:818
> >>  inet_sendmsg+0x19f/0x690 net/ipv4/af_inet.c:798
> >>  sock_sendmsg_nosec net/socket.c:629 [inline]
> >>  sock_sendmsg+0xd5/0x120 net/socket.c:639
> >>  ___sys_sendmsg+0x525/0x940 net/socket.c:2117
> >>  __sys_sendmmsg+0x240/0x6f0 net/socket.c:2212
> >>  __do_sys_sendmmsg net/socket.c:2241 [inline]
> >>  __se_sys_sendmmsg net/socket.c:2238 [inline]
> >>  __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2238
> >>  do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
> >>  entry_SYSCALL_64_after_hwframe+0x49/0xbe
> >> RIP: 0033:0x445d09
> >> RSP: 002b:7f3c7eff5d88 EFLAGS: 0293 ORIG_RAX: 0133
> >> RAX: ffda RBX: 006dac40 RCX: 00445d09
> >> RDX: 0001 RSI: 00
> >>
> >>
> >> ---
> >> This bug is generated by a bot. It may contain errors.
> >> See https://goo.gl/tpsmEJ for more information about syzbot.
> >> syzbot engineers can be reached at syzkal...@googlegroups.com.
> >>
> >> syzbot will keep track of this bug report.
> >> If you forgot to add the Reported-by tag,

Re: BUG: please report to d...@vger.kernel.org => prev = 0, last = 0 at net/dccp/ccids/lib/packet_history.c:LINE/tfrc_rx_his

2018-05-08 Thread Dmitry Vyukov 
On Wed, May 9, 2018 at 7:05 AM, Eric Biggers  wrote:
> On Sat, May 05, 2018 at 05:57:02PM -0700, syzbot wrote:
>> Hello,
>>
>> syzbot found the following crash on:
>>
>> HEAD commit:c1c07416cdd4 Merge tag 'kbuild-fixes-v4.17' of git://git.k..
>> git tree:   upstream
>> console output: https://syzkaller.appspot.com/x/log.txt?x=13d5de4780
>> kernel config:  https://syzkaller.appspot.com/x/.config?x=5a1dc06635c10d27
>> dashboard link: https://syzkaller.appspot.com/bug?extid=99858724c0ba555a12ea
>> compiler:   gcc (GCC) 8.0.1 20180413 (experimental)
>> syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=170afde780
>> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=141b4be780
>>
>> IMPORTANT: if you fix the bug, please add the following tag to the commit:
>> Reported-by: syzbot+99858724c0ba555a1...@syzkaller.appspotmail.com
>>
>> random: sshd: uninitialized urandom read (32 bytes read)
>> random: sshd: uninitialized urandom read (32 bytes read)
>> random: sshd: uninitialized urandom read (32 bytes read)
>> random: sshd: uninitialized urandom read (32 bytes read)
>> BUG: please report to d...@vger.kernel.org => prev = 0, last = 0 at
>> net/dccp/ccids/lib/packet_history.c:425/tfrc_rx_hist_sample_rtt()
>> CPU: 0 PID: 4495 Comm: syz-executor551 Not tainted 4.17.0-rc3+ #34
>> 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+0x1b9/0x294 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+0x5c8/0xed0 net/dccp/ccids/ccid3.c:765
>>  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:654
>>  sk_backlog_rcv include/net/sock.h:909 [inline]
>>  __sk_receive_skb+0x3a2/0xd60 net/core/sock.c:513
>>  dccp_v4_rcv+0x10e5/0x1f3f net/dccp/ipv4.c:875
>>  ip_local_deliver_finish+0x2e3/0xd80 net/ipv4/ip_input.c:215
>>  NF_HOOK include/linux/netfilter.h:288 [inline]
>>  ip_local_deliver+0x1e1/0x720 net/ipv4/ip_input.c:256
>>  dst_input include/net/dst.h:450 [inline]
>>  ip_rcv_finish+0x81b/0x2200 net/ipv4/ip_input.c:396
>>  NF_HOOK include/linux/netfilter.h:288 [inline]
>>  ip_rcv+0xb70/0x143d net/ipv4/ip_input.c:492
>>  __netif_receive_skb_core+0x26f5/0x3630 net/core/dev.c:4592
>>  __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:4657
>>  process_backlog+0x219/0x760 net/core/dev.c:5337
>>  napi_poll net/core/dev.c:5735 [inline]
>>  net_rx_action+0x7b7/0x1930 net/core/dev.c:5801
>>  __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285
>>  do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1046
>>  
>>  do_softirq.part.17+0x14d/0x190 kernel/softirq.c:329
>>  do_softirq arch/x86/include/asm/preempt.h:23 [inline]
>>  __local_bh_enable_ip+0x1ec/0x230 kernel/softirq.c:182
>>  local_bh_enable include/linux/bottom_half.h:32 [inline]
>>  rcu_read_unlock_bh include/linux/rcupdate.h:728 [inline]
>>  ip_finish_output2+0xab2/0x1840 net/ipv4/ip_output.c:231
>>  ip_finish_output+0x828/0xf80 net/ipv4/ip_output.c:317
>>  NF_HOOK_COND include/linux/netfilter.h:277 [inline]
>>  ip_output+0x21b/0x850 net/ipv4/ip_output.c:405
>>  dst_output include/net/dst.h:444 [inline]
>>  ip_local_out+0xc5/0x1b0 net/ipv4/ip_output.c:124
>>  ip_queue_xmit+0x9d7/0x1f70 net/ipv4/ip_output.c:504
>>  dccp_transmit_skb+0x999/0x12e0 net/dccp/output.c:142
>>  dccp_xmit_packet+0x250/0x790 net/dccp/output.c:281
>>  dccp_write_xmit+0x190/0x1f0 net/dccp/output.c:363
>>  dccp_sendmsg+0x8c7/0x1020 net/dccp/proto.c:818
>>  inet_sendmsg+0x19f/0x690 net/ipv4/af_inet.c:798
>>  sock_sendmsg_nosec net/socket.c:629 [inline]
>>  sock_sendmsg+0xd5/0x120 net/socket.c:639
>>  ___sys_sendmsg+0x525/0x940 net/socket.c:2117
>>  __sys_sendmmsg+0x240/0x6f0 net/socket.c:2212
>>  __do_sys_sendmmsg net/socket.c:2241 [inline]
>>  __se_sys_sendmmsg net/socket.c:2238 [inline]
>>  __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2238
>>  do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
>>  entry_SYSCALL_64_after_hwframe+0x49/0xbe
>> RIP: 0033:0x445d09
>> RSP: 002b:7f3c7eff5d88 EFLAGS: 0293 ORIG_RAX: 0133
>> RAX: ffda RBX: 006dac40 RCX: 00445d09
>> RDX: 0001 RSI: 00
>>
>>
>> ---
>> This bug is generated by a bot. It may contain errors.
>> See https://goo.gl/tpsmEJ for more information about syzbot.
>> syzbot engineers can be reached at syzkal...@googlegroups.com.
>>
>> syzbot will keep track of this bug report.
>> If you forgot to add the Reported-by tag, once the fix for this bug is
>> merged
>> into any tree, please reply to this email with:
>> #syz fix: exact-commit-title
>> If you want to test a patch for this bug, please reply with:
>> #syz test: git://repo/address.git branch
>> and provide the patch inline or

Re: BUG: please report to d...@vger.kernel.org => prev = 0, last = 0 at net/dccp/ccids/lib/packet_history.c:LINE/tfrc_rx_his

2018-05-08 Thread Dmitry Vyukov 
On Wed, May 9, 2018 at 7:05 AM, Eric Biggers  wrote:
> On Sat, May 05, 2018 at 05:57:02PM -0700, syzbot wrote:
>> Hello,
>>
>> syzbot found the following crash on:
>>
>> HEAD commit:c1c07416cdd4 Merge tag 'kbuild-fixes-v4.17' of git://git.k..
>> git tree:   upstream
>> console output: https://syzkaller.appspot.com/x/log.txt?x=13d5de4780
>> kernel config:  https://syzkaller.appspot.com/x/.config?x=5a1dc06635c10d27
>> dashboard link: https://syzkaller.appspot.com/bug?extid=99858724c0ba555a12ea
>> compiler:   gcc (GCC) 8.0.1 20180413 (experimental)
>> syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=170afde780
>> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=141b4be780
>>
>> IMPORTANT: if you fix the bug, please add the following tag to the commit:
>> Reported-by: syzbot+99858724c0ba555a1...@syzkaller.appspotmail.com
>>
>> random: sshd: uninitialized urandom read (32 bytes read)
>> random: sshd: uninitialized urandom read (32 bytes read)
>> random: sshd: uninitialized urandom read (32 bytes read)
>> random: sshd: uninitialized urandom read (32 bytes read)
>> BUG: please report to d...@vger.kernel.org => prev = 0, last = 0 at
>> net/dccp/ccids/lib/packet_history.c:425/tfrc_rx_hist_sample_rtt()
>> CPU: 0 PID: 4495 Comm: syz-executor551 Not tainted 4.17.0-rc3+ #34
>> 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+0x1b9/0x294 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+0x5c8/0xed0 net/dccp/ccids/ccid3.c:765
>>  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:654
>>  sk_backlog_rcv include/net/sock.h:909 [inline]
>>  __sk_receive_skb+0x3a2/0xd60 net/core/sock.c:513
>>  dccp_v4_rcv+0x10e5/0x1f3f net/dccp/ipv4.c:875
>>  ip_local_deliver_finish+0x2e3/0xd80 net/ipv4/ip_input.c:215
>>  NF_HOOK include/linux/netfilter.h:288 [inline]
>>  ip_local_deliver+0x1e1/0x720 net/ipv4/ip_input.c:256
>>  dst_input include/net/dst.h:450 [inline]
>>  ip_rcv_finish+0x81b/0x2200 net/ipv4/ip_input.c:396
>>  NF_HOOK include/linux/netfilter.h:288 [inline]
>>  ip_rcv+0xb70/0x143d net/ipv4/ip_input.c:492
>>  __netif_receive_skb_core+0x26f5/0x3630 net/core/dev.c:4592
>>  __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:4657
>>  process_backlog+0x219/0x760 net/core/dev.c:5337
>>  napi_poll net/core/dev.c:5735 [inline]
>>  net_rx_action+0x7b7/0x1930 net/core/dev.c:5801
>>  __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285
>>  do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1046
>>  
>>  do_softirq.part.17+0x14d/0x190 kernel/softirq.c:329
>>  do_softirq arch/x86/include/asm/preempt.h:23 [inline]
>>  __local_bh_enable_ip+0x1ec/0x230 kernel/softirq.c:182
>>  local_bh_enable include/linux/bottom_half.h:32 [inline]
>>  rcu_read_unlock_bh include/linux/rcupdate.h:728 [inline]
>>  ip_finish_output2+0xab2/0x1840 net/ipv4/ip_output.c:231
>>  ip_finish_output+0x828/0xf80 net/ipv4/ip_output.c:317
>>  NF_HOOK_COND include/linux/netfilter.h:277 [inline]
>>  ip_output+0x21b/0x850 net/ipv4/ip_output.c:405
>>  dst_output include/net/dst.h:444 [inline]
>>  ip_local_out+0xc5/0x1b0 net/ipv4/ip_output.c:124
>>  ip_queue_xmit+0x9d7/0x1f70 net/ipv4/ip_output.c:504
>>  dccp_transmit_skb+0x999/0x12e0 net/dccp/output.c:142
>>  dccp_xmit_packet+0x250/0x790 net/dccp/output.c:281
>>  dccp_write_xmit+0x190/0x1f0 net/dccp/output.c:363
>>  dccp_sendmsg+0x8c7/0x1020 net/dccp/proto.c:818
>>  inet_sendmsg+0x19f/0x690 net/ipv4/af_inet.c:798
>>  sock_sendmsg_nosec net/socket.c:629 [inline]
>>  sock_sendmsg+0xd5/0x120 net/socket.c:639
>>  ___sys_sendmsg+0x525/0x940 net/socket.c:2117
>>  __sys_sendmmsg+0x240/0x6f0 net/socket.c:2212
>>  __do_sys_sendmmsg net/socket.c:2241 [inline]
>>  __se_sys_sendmmsg net/socket.c:2238 [inline]
>>  __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2238
>>  do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
>>  entry_SYSCALL_64_after_hwframe+0x49/0xbe
>> RIP: 0033:0x445d09
>> RSP: 002b:7f3c7eff5d88 EFLAGS: 0293 ORIG_RAX: 0133
>> RAX: ffda RBX: 006dac40 RCX: 00445d09
>> RDX: 0001 RSI: 00
>>
>>
>> ---
>> This bug is generated by a bot. It may contain errors.
>> See https://goo.gl/tpsmEJ for more information about syzbot.
>> syzbot engineers can be reached at syzkal...@googlegroups.com.
>>
>> syzbot will keep track of this bug report.
>> If you forgot to add the Reported-by tag, once the fix for this bug is
>> merged
>> into any tree, please reply to this email with:
>> #syz fix: exact-commit-title
>> If you want to test a patch for this bug, please reply with:
>> #syz test: git://repo/address.git branch
>> and provide the patch inline or as an attachment.
>>

Re: BUG: please report to d...@vger.kernel.org => prev = 0, last = 0 at net/dccp/ccids/lib/packet_history.c:LINE/tfrc_rx_his

2018-05-08 Thread Eric Biggers 
On Sat, May 05, 2018 at 05:57:02PM -0700, syzbot wrote:
> Hello,
> 
> syzbot found the following crash on:
> 
> HEAD commit:c1c07416cdd4 Merge tag 'kbuild-fixes-v4.17' of git://git.k..
> git tree:   upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=13d5de4780
> kernel config:  https://syzkaller.appspot.com/x/.config?x=5a1dc06635c10d27
> dashboard link: https://syzkaller.appspot.com/bug?extid=99858724c0ba555a12ea
> compiler:   gcc (GCC) 8.0.1 20180413 (experimental)
> syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=170afde780
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=141b4be780
> 
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+99858724c0ba555a1...@syzkaller.appspotmail.com
> 
> random: sshd: uninitialized urandom read (32 bytes read)
> random: sshd: uninitialized urandom read (32 bytes read)
> random: sshd: uninitialized urandom read (32 bytes read)
> random: sshd: uninitialized urandom read (32 bytes read)
> BUG: please report to d...@vger.kernel.org => prev = 0, last = 0 at
> net/dccp/ccids/lib/packet_history.c:425/tfrc_rx_hist_sample_rtt()
> CPU: 0 PID: 4495 Comm: syz-executor551 Not tainted 4.17.0-rc3+ #34
> 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+0x1b9/0x294 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+0x5c8/0xed0 net/dccp/ccids/ccid3.c:765
>  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:654
>  sk_backlog_rcv include/net/sock.h:909 [inline]
>  __sk_receive_skb+0x3a2/0xd60 net/core/sock.c:513
>  dccp_v4_rcv+0x10e5/0x1f3f net/dccp/ipv4.c:875
>  ip_local_deliver_finish+0x2e3/0xd80 net/ipv4/ip_input.c:215
>  NF_HOOK include/linux/netfilter.h:288 [inline]
>  ip_local_deliver+0x1e1/0x720 net/ipv4/ip_input.c:256
>  dst_input include/net/dst.h:450 [inline]
>  ip_rcv_finish+0x81b/0x2200 net/ipv4/ip_input.c:396
>  NF_HOOK include/linux/netfilter.h:288 [inline]
>  ip_rcv+0xb70/0x143d net/ipv4/ip_input.c:492
>  __netif_receive_skb_core+0x26f5/0x3630 net/core/dev.c:4592
>  __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:4657
>  process_backlog+0x219/0x760 net/core/dev.c:5337
>  napi_poll net/core/dev.c:5735 [inline]
>  net_rx_action+0x7b7/0x1930 net/core/dev.c:5801
>  __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285
>  do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1046
>  
>  do_softirq.part.17+0x14d/0x190 kernel/softirq.c:329
>  do_softirq arch/x86/include/asm/preempt.h:23 [inline]
>  __local_bh_enable_ip+0x1ec/0x230 kernel/softirq.c:182
>  local_bh_enable include/linux/bottom_half.h:32 [inline]
>  rcu_read_unlock_bh include/linux/rcupdate.h:728 [inline]
>  ip_finish_output2+0xab2/0x1840 net/ipv4/ip_output.c:231
>  ip_finish_output+0x828/0xf80 net/ipv4/ip_output.c:317
>  NF_HOOK_COND include/linux/netfilter.h:277 [inline]
>  ip_output+0x21b/0x850 net/ipv4/ip_output.c:405
>  dst_output include/net/dst.h:444 [inline]
>  ip_local_out+0xc5/0x1b0 net/ipv4/ip_output.c:124
>  ip_queue_xmit+0x9d7/0x1f70 net/ipv4/ip_output.c:504
>  dccp_transmit_skb+0x999/0x12e0 net/dccp/output.c:142
>  dccp_xmit_packet+0x250/0x790 net/dccp/output.c:281
>  dccp_write_xmit+0x190/0x1f0 net/dccp/output.c:363
>  dccp_sendmsg+0x8c7/0x1020 net/dccp/proto.c:818
>  inet_sendmsg+0x19f/0x690 net/ipv4/af_inet.c:798
>  sock_sendmsg_nosec net/socket.c:629 [inline]
>  sock_sendmsg+0xd5/0x120 net/socket.c:639
>  ___sys_sendmsg+0x525/0x940 net/socket.c:2117
>  __sys_sendmmsg+0x240/0x6f0 net/socket.c:2212
>  __do_sys_sendmmsg net/socket.c:2241 [inline]
>  __se_sys_sendmmsg net/socket.c:2238 [inline]
>  __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2238
>  do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
>  entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x445d09
> RSP: 002b:7f3c7eff5d88 EFLAGS: 0293 ORIG_RAX: 0133
> RAX: ffda RBX: 006dac40 RCX: 00445d09
> RDX: 0001 RSI: 00
> 
> 
> ---
> This bug is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkal...@googlegroups.com.
> 
> syzbot will keep track of this bug report.
> If you forgot to add the Reported-by tag, once the fix for this bug is
> merged
> into any tree, please reply to this email with:
> #syz fix: exact-commit-title
> If you want to test a patch for this bug, please reply with:
> #syz test: git://repo/address.git branch
> and provide the patch inline or as an attachment.
> To mark this as a duplicate of another syzbot report, please reply with:
> #syz dup: exact-subject-of-another-report

There's already a bug report

Re: BUG: please report to d...@vger.kernel.org => prev = 0, last = 0 at net/dccp/ccids/lib/packet_history.c:LINE/tfrc_rx_his

2018-05-08 Thread Eric Biggers 
On Sat, May 05, 2018 at 05:57:02PM -0700, syzbot wrote:
> Hello,
> 
> syzbot found the following crash on:
> 
> HEAD commit:c1c07416cdd4 Merge tag 'kbuild-fixes-v4.17' of git://git.k..
> git tree:   upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=13d5de4780
> kernel config:  https://syzkaller.appspot.com/x/.config?x=5a1dc06635c10d27
> dashboard link: https://syzkaller.appspot.com/bug?extid=99858724c0ba555a12ea
> compiler:   gcc (GCC) 8.0.1 20180413 (experimental)
> syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=170afde780
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=141b4be780
> 
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+99858724c0ba555a1...@syzkaller.appspotmail.com
> 
> random: sshd: uninitialized urandom read (32 bytes read)
> random: sshd: uninitialized urandom read (32 bytes read)
> random: sshd: uninitialized urandom read (32 bytes read)
> random: sshd: uninitialized urandom read (32 bytes read)
> BUG: please report to d...@vger.kernel.org => prev = 0, last = 0 at
> net/dccp/ccids/lib/packet_history.c:425/tfrc_rx_hist_sample_rtt()
> CPU: 0 PID: 4495 Comm: syz-executor551 Not tainted 4.17.0-rc3+ #34
> 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+0x1b9/0x294 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+0x5c8/0xed0 net/dccp/ccids/ccid3.c:765
>  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:654
>  sk_backlog_rcv include/net/sock.h:909 [inline]
>  __sk_receive_skb+0x3a2/0xd60 net/core/sock.c:513
>  dccp_v4_rcv+0x10e5/0x1f3f net/dccp/ipv4.c:875
>  ip_local_deliver_finish+0x2e3/0xd80 net/ipv4/ip_input.c:215
>  NF_HOOK include/linux/netfilter.h:288 [inline]
>  ip_local_deliver+0x1e1/0x720 net/ipv4/ip_input.c:256
>  dst_input include/net/dst.h:450 [inline]
>  ip_rcv_finish+0x81b/0x2200 net/ipv4/ip_input.c:396
>  NF_HOOK include/linux/netfilter.h:288 [inline]
>  ip_rcv+0xb70/0x143d net/ipv4/ip_input.c:492
>  __netif_receive_skb_core+0x26f5/0x3630 net/core/dev.c:4592
>  __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:4657
>  process_backlog+0x219/0x760 net/core/dev.c:5337
>  napi_poll net/core/dev.c:5735 [inline]
>  net_rx_action+0x7b7/0x1930 net/core/dev.c:5801
>  __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285
>  do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1046
>  
>  do_softirq.part.17+0x14d/0x190 kernel/softirq.c:329
>  do_softirq arch/x86/include/asm/preempt.h:23 [inline]
>  __local_bh_enable_ip+0x1ec/0x230 kernel/softirq.c:182
>  local_bh_enable include/linux/bottom_half.h:32 [inline]
>  rcu_read_unlock_bh include/linux/rcupdate.h:728 [inline]
>  ip_finish_output2+0xab2/0x1840 net/ipv4/ip_output.c:231
>  ip_finish_output+0x828/0xf80 net/ipv4/ip_output.c:317
>  NF_HOOK_COND include/linux/netfilter.h:277 [inline]
>  ip_output+0x21b/0x850 net/ipv4/ip_output.c:405
>  dst_output include/net/dst.h:444 [inline]
>  ip_local_out+0xc5/0x1b0 net/ipv4/ip_output.c:124
>  ip_queue_xmit+0x9d7/0x1f70 net/ipv4/ip_output.c:504
>  dccp_transmit_skb+0x999/0x12e0 net/dccp/output.c:142
>  dccp_xmit_packet+0x250/0x790 net/dccp/output.c:281
>  dccp_write_xmit+0x190/0x1f0 net/dccp/output.c:363
>  dccp_sendmsg+0x8c7/0x1020 net/dccp/proto.c:818
>  inet_sendmsg+0x19f/0x690 net/ipv4/af_inet.c:798
>  sock_sendmsg_nosec net/socket.c:629 [inline]
>  sock_sendmsg+0xd5/0x120 net/socket.c:639
>  ___sys_sendmsg+0x525/0x940 net/socket.c:2117
>  __sys_sendmmsg+0x240/0x6f0 net/socket.c:2212
>  __do_sys_sendmmsg net/socket.c:2241 [inline]
>  __se_sys_sendmmsg net/socket.c:2238 [inline]
>  __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2238
>  do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
>  entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x445d09
> RSP: 002b:7f3c7eff5d88 EFLAGS: 0293 ORIG_RAX: 0133
> RAX: ffda RBX: 006dac40 RCX: 00445d09
> RDX: 0001 RSI: 00
> 
> 
> ---
> This bug is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkal...@googlegroups.com.
> 
> syzbot will keep track of this bug report.
> If you forgot to add the Reported-by tag, once the fix for this bug is
> merged
> into any tree, please reply to this email with:
> #syz fix: exact-commit-title
> If you want to test a patch for this bug, please reply with:
> #syz test: git://repo/address.git branch
> and provide the patch inline or as an attachment.
> To mark this as a duplicate of another syzbot report, please reply with:
> #syz dup: exact-subject-of-another-report

There's already a bug report

BUG: please report to d...@vger.kernel.org => prev = 0, last = 0 at net/dccp/ccids/lib/packet_history.c:LINE/tfrc_rx_his

2018-05-05 Thread syzbot 

Hello,

syzbot found the following crash on:

HEAD commit:c1c07416cdd4 Merge tag 'kbuild-fixes-v4.17' of git://git.k..
git tree:   upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13d5de4780
kernel config:  https://syzkaller.appspot.com/x/.config?x=5a1dc06635c10d27
dashboard link: https://syzkaller.appspot.com/bug?extid=99858724c0ba555a12ea
compiler:   gcc (GCC) 8.0.1 20180413 (experimental)
syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=170afde780
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=141b4be780

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+99858724c0ba555a1...@syzkaller.appspotmail.com

random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
BUG: please report to d...@vger.kernel.org => prev = 0, last = 0 at  
net/dccp/ccids/lib/packet_history.c:425/tfrc_rx_hist_sample_rtt()

CPU: 0 PID: 4495 Comm: syz-executor551 Not tainted 4.17.0-rc3+ #34
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+0x1b9/0x294 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+0x5c8/0xed0 net/dccp/ccids/ccid3.c:765
 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:654
 sk_backlog_rcv include/net/sock.h:909 [inline]
 __sk_receive_skb+0x3a2/0xd60 net/core/sock.c:513
 dccp_v4_rcv+0x10e5/0x1f3f net/dccp/ipv4.c:875
 ip_local_deliver_finish+0x2e3/0xd80 net/ipv4/ip_input.c:215
 NF_HOOK include/linux/netfilter.h:288 [inline]
 ip_local_deliver+0x1e1/0x720 net/ipv4/ip_input.c:256
 dst_input include/net/dst.h:450 [inline]
 ip_rcv_finish+0x81b/0x2200 net/ipv4/ip_input.c:396
 NF_HOOK include/linux/netfilter.h:288 [inline]
 ip_rcv+0xb70/0x143d net/ipv4/ip_input.c:492
 __netif_receive_skb_core+0x26f5/0x3630 net/core/dev.c:4592
 __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:4657
 process_backlog+0x219/0x760 net/core/dev.c:5337
 napi_poll net/core/dev.c:5735 [inline]
 net_rx_action+0x7b7/0x1930 net/core/dev.c:5801
 __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1046
 
 do_softirq.part.17+0x14d/0x190 kernel/softirq.c:329
 do_softirq arch/x86/include/asm/preempt.h:23 [inline]
 __local_bh_enable_ip+0x1ec/0x230 kernel/softirq.c:182
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:728 [inline]
 ip_finish_output2+0xab2/0x1840 net/ipv4/ip_output.c:231
 ip_finish_output+0x828/0xf80 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:277 [inline]
 ip_output+0x21b/0x850 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:444 [inline]
 ip_local_out+0xc5/0x1b0 net/ipv4/ip_output.c:124
 ip_queue_xmit+0x9d7/0x1f70 net/ipv4/ip_output.c:504
 dccp_transmit_skb+0x999/0x12e0 net/dccp/output.c:142
 dccp_xmit_packet+0x250/0x790 net/dccp/output.c:281
 dccp_write_xmit+0x190/0x1f0 net/dccp/output.c:363
 dccp_sendmsg+0x8c7/0x1020 net/dccp/proto.c:818
 inet_sendmsg+0x19f/0x690 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:639
 ___sys_sendmsg+0x525/0x940 net/socket.c:2117
 __sys_sendmmsg+0x240/0x6f0 net/socket.c:2212
 __do_sys_sendmmsg net/socket.c:2241 [inline]
 __se_sys_sendmmsg net/socket.c:2238 [inline]
 __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2238
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x445d09
RSP: 002b:7f3c7eff5d88 EFLAGS: 0293 ORIG_RAX: 0133
RAX: ffda RBX: 006dac40 RCX: 00445d09
RDX: 0001 RSI: 00


---
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BUG: please report to d...@vger.kernel.org => prev = 0, last = 0 at net/dccp/ccids/lib/packet_history.c:LINE/tfrc_rx_his

2018-05-05 Thread syzbot 

Hello,

syzbot found the following crash on:

HEAD commit:c1c07416cdd4 Merge tag 'kbuild-fixes-v4.17' of git://git.k..
git tree:   upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13d5de4780
kernel config:  https://syzkaller.appspot.com/x/.config?x=5a1dc06635c10d27
dashboard link: https://syzkaller.appspot.com/bug?extid=99858724c0ba555a12ea
compiler:   gcc (GCC) 8.0.1 20180413 (experimental)
syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=170afde780
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=141b4be780

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+99858724c0ba555a1...@syzkaller.appspotmail.com

random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
BUG: please report to d...@vger.kernel.org => prev = 0, last = 0 at  
net/dccp/ccids/lib/packet_history.c:425/tfrc_rx_hist_sample_rtt()

CPU: 0 PID: 4495 Comm: syz-executor551 Not tainted 4.17.0-rc3+ #34
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+0x1b9/0x294 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+0x5c8/0xed0 net/dccp/ccids/ccid3.c:765
 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:654
 sk_backlog_rcv include/net/sock.h:909 [inline]
 __sk_receive_skb+0x3a2/0xd60 net/core/sock.c:513
 dccp_v4_rcv+0x10e5/0x1f3f net/dccp/ipv4.c:875
 ip_local_deliver_finish+0x2e3/0xd80 net/ipv4/ip_input.c:215
 NF_HOOK include/linux/netfilter.h:288 [inline]
 ip_local_deliver+0x1e1/0x720 net/ipv4/ip_input.c:256
 dst_input include/net/dst.h:450 [inline]
 ip_rcv_finish+0x81b/0x2200 net/ipv4/ip_input.c:396
 NF_HOOK include/linux/netfilter.h:288 [inline]
 ip_rcv+0xb70/0x143d net/ipv4/ip_input.c:492
 __netif_receive_skb_core+0x26f5/0x3630 net/core/dev.c:4592
 __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:4657
 process_backlog+0x219/0x760 net/core/dev.c:5337
 napi_poll net/core/dev.c:5735 [inline]
 net_rx_action+0x7b7/0x1930 net/core/dev.c:5801
 __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1046
 
 do_softirq.part.17+0x14d/0x190 kernel/softirq.c:329
 do_softirq arch/x86/include/asm/preempt.h:23 [inline]
 __local_bh_enable_ip+0x1ec/0x230 kernel/softirq.c:182
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:728 [inline]
 ip_finish_output2+0xab2/0x1840 net/ipv4/ip_output.c:231
 ip_finish_output+0x828/0xf80 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:277 [inline]
 ip_output+0x21b/0x850 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:444 [inline]
 ip_local_out+0xc5/0x1b0 net/ipv4/ip_output.c:124
 ip_queue_xmit+0x9d7/0x1f70 net/ipv4/ip_output.c:504
 dccp_transmit_skb+0x999/0x12e0 net/dccp/output.c:142
 dccp_xmit_packet+0x250/0x790 net/dccp/output.c:281
 dccp_write_xmit+0x190/0x1f0 net/dccp/output.c:363
 dccp_sendmsg+0x8c7/0x1020 net/dccp/proto.c:818
 inet_sendmsg+0x19f/0x690 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:639
 ___sys_sendmsg+0x525/0x940 net/socket.c:2117
 __sys_sendmmsg+0x240/0x6f0 net/socket.c:2212
 __do_sys_sendmmsg net/socket.c:2241 [inline]
 __se_sys_sendmmsg net/socket.c:2238 [inline]
 __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2238
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x445d09
RSP: 002b:7f3c7eff5d88 EFLAGS: 0293 ORIG_RAX: 0133
RAX: ffda RBX: 006dac40 RCX: 00445d09
RDX: 0001 RSI: 00


---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkal...@googlegroups.com.

syzbot will keep track of this bug report.
If you forgot to add the Reported-by tag, once the fix for this bug is  
merged

into any tree, please reply to this email with:
#syz fix: exact-commit-title
If you want to test a patch for this bug, please reply with:
#syz test: git://repo/address.git branch
and provide the patch inline or as an attachment.
To mark this as a duplicate of another syzbot report, please reply with:
#syz dup: exact-subject-of-another-report
If it's a one-off invalid bug report, please reply with:
#syz invalid
Note: if the crash happens again, it will cause creation of a new bug  
report.

Note: all commands must start from beginning of the line in the email body.