Hello, syzbot found the following issue on: HEAD commit: c7d102232649 Merge tag 'net-5.14-rc4' of git://git.kernel... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1308610a300000 kernel config: https://syzkaller.appspot.com/x/.config?x=6cc86e19161c9d37 dashboard link: https://syzkaller.appspot.com/bug?extid=9981a614060dcee6eeca compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.1 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15874fda300000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10a507b6300000 The issue was bisected to: commit 9d71dd0c70099914fcd063135da3c580865e924c Author: The j1939 authors <linux-can@xxxxxxxxxxxxxxx> Date: Mon Oct 8 09:48:36 2018 +0000 can: add support of SAE J1939 protocol bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=17a70c66300000 final oops: https://syzkaller.appspot.com/x/report.txt?x=14670c66300000 console output: https://syzkaller.appspot.com/x/log.txt?x=10670c66300000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+9981a614060dcee6eeca@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol") vcan0: j1939_tp_rxtimer: 0xffff888012588c00: rx timeout, send abort vcan0: j1939_xtp_rx_abort_one: 0xffff88802f335800: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. ------------[ cut here ]------------ WARNING: CPU: 1 PID: 19 at net/can/j1939/transport.c:1085 j1939_session_deactivate net/can/j1939/transport.c:1085 [inline] WARNING: CPU: 1 PID: 19 at net/can/j1939/transport.c:1085 j1939_session_deactivate_activate_next net/can/j1939/transport.c:1095 [inline] WARNING: CPU: 1 PID: 19 at net/can/j1939/transport.c:1085 j1939_xtp_rx_abort_one+0x666/0x790 net/can/j1939/transport.c:1329 Modules linked in: CPU: 1 PID: 19 Comm: ksoftirqd/1 Not tainted 5.14.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:j1939_session_deactivate net/can/j1939/transport.c:1085 [inline] RIP: 0010:j1939_session_deactivate_activate_next net/can/j1939/transport.c:1095 [inline] RIP: 0010:j1939_xtp_rx_abort_one+0x666/0x790 net/can/j1939/transport.c:1329 Code: e9 88 fa ff ff e8 da 5f 8b f8 4c 89 f7 be 03 00 00 00 48 83 c4 20 5b 41 5c 41 5d 41 5e 41 5f 5d e9 af 1f 11 fb e8 ba 5f 8b f8 <0f> 0b e9 4b fd ff ff e8 ae 5f 8b f8 0f 0b e9 ca fd ff ff 89 e9 80 RSP: 0018:ffffc90000d975a0 EFLAGS: 00010246 RAX: ffffffff88f4c4f6 RBX: 0000000000000001 RCX: ffff8880124354c0 RDX: 0000000000000301 RSI: 0000000000000001 RDI: 0000000000000002 RBP: 1ffff11005e66b00 R08: ffffffff88f4c23a R09: ffffed1005e66b06 R10: ffffed1005e66b06 R11: 0000000000000000 R12: ffff88802f335800 R13: 0000000000000009 R14: ffff8880221ad070 R15: ffff88802f335828 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004b8120 CR3: 00000000334c1000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: j1939_xtp_rx_abort net/can/j1939/transport.c:1340 [inline] j1939_tp_cmd_recv+0x374/0x1200 net/can/j1939/transport.c:2065 j1939_tp_recv+0x1f7/0x540 net/can/j1939/transport.c:2098 j1939_can_recv+0x652/0xa10 net/can/j1939/main.c:101 deliver net/can/af_can.c:574 [inline] can_rcv_filter+0x35e/0x800 net/can/af_can.c:608 can_receive+0x2e8/0x410 net/can/af_can.c:665 can_rcv+0xda/0x1f0 net/can/af_can.c:696 __netif_receive_skb_one_core net/core/dev.c:5498 [inline] __netif_receive_skb+0x1d1/0x500 net/core/dev.c:5612 process_backlog+0x4d8/0x940 net/core/dev.c:6492 __napi_poll+0xba/0x4f0 net/core/dev.c:7047 napi_poll net/core/dev.c:7114 [inline] net_rx_action+0x62c/0xf30 net/core/dev.c:7201 __do_softirq+0x372/0x783 kernel/softirq.c:558 run_ksoftirqd+0xa2/0x100 kernel/softirq.c:920 smpboot_thread_fn+0x533/0x9d0 kernel/smpboot.c:164 kthread+0x453/0x480 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 --- This report 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 issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. For information about bisection process see: https://goo.gl/tpsmEJ#bisection syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches
