On Tue, Oct 23, 2018 at 03:13:02AM -0700, syzbot wrote: > Hello, > > syzbot found the following crash on: > > HEAD commit: ca9eb48fe01f Merge tag 'regulator-v5.0' of git://git.kerne.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=1482a939400000 > kernel config: https://syzkaller.appspot.com/x/.config?x=963b24abf3f7c2d8 > dashboard link: https://syzkaller.appspot.com/bug?extid=e786ba000564d103a6fe > 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+e786ba000564d103a6fe@xxxxxxxxxxxxxxxxxxxxxxxxx > > input: syz0 as /devices/virtual/input/input6 > BUG: please report to dccp@xxxxxxxxxxxxxxx => prev = 2, last = 2 at > net/dccp/ccids/lib/packet_history.c:425/tfrc_rx_hist_sample_rtt() > CPU: 1 PID: 18 Comm: ksoftirqd/1 Not tainted 4.19.0+ #298 > 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+0x1c4/0x2b6 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:931 [inline] > __sk_receive_skb+0x3e5/0xec0 net/core/sock.c:473 > 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+0x1e9/0x750 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+0xed/0x600 net/ipv4/ip_input.c:524 > __netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4913 > __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:5023 > process_backlog+0x218/0x6f0 net/core/dev.c:5829 > napi_poll net/core/dev.c:6249 [inline] > net_rx_action+0x7c5/0x1950 net/core/dev.c:6315 > __do_softirq+0x30c/0xb03 kernel/softirq.c:292 > run_ksoftirqd+0x94/0x100 kernel/softirq.c:653 > smpboot_thread_fn+0x68b/0xa00 kernel/smpboot.c:164 > kthread+0x35a/0x420 kernel/kthread.c:246 > ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413 > net_ratelimit: 18 callbacks suppressed > dccp_close: ABORT with 105978 bytes unread > input: syz0 as /devices/virtual/input/input7 > input: syz0 as /devices/virtual/input/input8 > dccp_close: ABORT with 52730 bytes unread > input: syz0 as /devices/virtual/input/input9 > dccp_close: ABORT with 105978 bytes unread > dccp_close: ABORT with 105978 bytes unread > dccp_close: ABORT with 77306 bytes unread > dccp_close: ABORT with 89594 bytes unread > input: syz0 as /devices/virtual/input/input10 > input: syz0 as /devices/virtual/input/input11 > input: syz0 as /devices/virtual/input/input12 > input: syz0 as /devices/virtual/input/input13 > input: syz0 as /devices/virtual/input/input14 > input: syz0 as /devices/virtual/input/input15 > input: syz0 as /devices/virtual/input/input16 > input: syz0 as /devices/virtual/input/input17 > input: syz0 as /devices/virtual/input/input18 > > > --- > 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 syzkaller@xxxxxxxxxxxxxxxx. > > syzbot will keep track of this bug report. See: > https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with > syzbot. > #syz dup: BUG: please report to dccp@xxxxxxxxxxxxxxx => prev = 0, last = 0 at net/dccp/ccids/lib/packet_history.c:LINE/tfrc_rx_hist_sample_rtt() Still occurring, see existing thread with reproducer here: https://groups.google.com/d/msg/syzkaller-bugs/u5nq3PdPkIc/M7tbibYVCQAJ - Eric
