bisecting fixing commit since a844dc4c544291470aa69edbe2434b040794e269 building syzkaller on b31eda3df81f62eb7efde0c5d7a9f24ee7e34e6f testing commit a844dc4c544291470aa69edbe2434b040794e269 with gcc (GCC) 8.1.0 kernel signature: 6ba8c5e25f03ecf6c806844cabd7b00eee67a6e5a3c56e39ebfac7ca1d0199a7 all runs: crashed: kernel BUG at kernel/time/timer.c:LINE! testing current HEAD 050272a0423e68207fd2367831ae610680129062 testing commit 050272a0423e68207fd2367831ae610680129062 with gcc (GCC) 8.1.0 kernel signature: 54125a0de1ca490cf3fc15fd84d0a2b4283997bc3c02924faf83fc95a2619119 all runs: crashed: kernel BUG at kernel/time/timer.c:LINE! revisions tested: 2, total time: 23m46.044245814s (build: 16m56.783193877s, test: 5m58.965034508s) the crash still happens on HEAD commit msg: Linux 4.14.177 crash: kernel BUG at kernel/time/timer.c:LINE! sp2: Found TNC sp4: Found TNC sp5: Synchronizing with TNC sp3: Found TNC ------------[ cut here ]------------ kernel BUG at kernel/time/timer.c:1089! sp5: Found TNC invalid opcode: 0000 [#1] PREEMPT SMP KASAN Modules linked in: CPU: 0 PID: 7464 Comm: kworker/u4:6 Not tainted 4.14.177-syzkaller #0 sp0: Synchronizing with TNC Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound flush_to_ldisc task: ffff8880a476e0c0 task.stack: ffff888088940000 RIP: 0010:add_timer+0x5ec/0xab0 kernel/time/timer.c:1089 RSP: 0018:ffff888088947b40 EFLAGS: 00010282 RAX: 1ffff11013da9609 RBX: 1ffff11011128f6f RCX: 0000000000000000 RDX: dffffc0000000000 RSI: ffff8880a476e9c0 RDI: ffff88809ed4b048 RBP: ffff888088947c00 R08: ffff8880a476e9e0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000 R13: ffff88809fd0a760 R14: ffff888088947bd8 R15: ffff88809ed4b040 FS: 0000000000000000(0000) GS:ffff8880aec00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 sp1: Synchronizing with TNC CR2: 00007f5e1e58e5c0 CR3: 0000000094035000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: sp2: Synchronizing with TNC decode_prio_command drivers/net/hamradio/6pack.c:934 [inline] sixpack_decode drivers/net/hamradio/6pack.c:1003 [inline] sixpack_receive_buf+0x8ed/0x1180 drivers/net/hamradio/6pack.c:458 tty_ldisc_receive_buf+0xff/0x1b0 drivers/tty/tty_buffer.c:459 tty_port_default_receive_buf+0x5f/0x90 drivers/tty/tty_port.c:37 6pack: bad checksum 32 receive_buf drivers/tty/tty_buffer.c:475 [inline] flush_to_ldisc+0x197/0x390 drivers/tty/tty_buffer.c:527 process_one_work+0x79e/0x16c0 kernel/workqueue.c:2116 6pack: protocol violation worker_thread+0xcc/0xee0 kernel/workqueue.c:2250 kthread+0x338/0x400 kernel/kthread.c:232 6pack: protocol violation ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 6pack: protocol violation Code: 8b a5 58 ff ff ff 48 8b 9d 50 ff ff ff 4c 8b ad 48 ff ff ff 65 ff 0d 44 4e b3 7e 0f 85 e0 fd ff ff e8 7a 9f b1 ff e9 d6 fd ff ff <0f> 0b 0f 0b 4c 89 a5 68 ff ff ff e9 b2 fd ff ff 65 ff 05 1d 4e 6pack: bad checksum 32 RIP: add_timer+0x5ec/0xab0 kernel/time/timer.c:1089 RSP: ffff888088947b40 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation sp4: Synchronizing with TNC 6pack: protocol violation 6pack: protocol violation sp5: Synchronizing with TNC 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 13 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 52 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 19 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 13 6pack: protocol violation 6pack: bad checksum 13 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 52 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 52 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 19 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 13 6pack: protocol violation sp6: Synchronizing with TNC 6pack: protocol violation 6pack: bad checksum 19 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 32 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 13 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 52 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 52 6pack: protocol violation 6pack: bad checksum 19 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum f6 6pack: bad checksum 94 sp5: Found TNC 6pack: bad checksum 34 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation sp7: Synchronizing with TNC 6pack: protocol violation sp8: Synchronizing with TNC 6pack: protocol violation 6pack: protocol violation sp9: Synchronizing with TNC 6pack: protocol violation 6pack: bad checksum 19 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 32 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum f6 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 94 6pack: protocol violation 6pack: protocol violation sp2: Found TNC 6pack: protocol violation 6pack: bad checksum f6 6pack: protocol violation sp7: Synchronizing with TNC 6pack: bad checksum 13 6pack: bad checksum 34 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 94 sp10: Synchronizing with TNC 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation sp4: Found TNC 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum f6 6pack: bad checksum 94 sp0: Found TNC 6pack: bad checksum 34 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 34 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 13 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 13 6pack: bad checksum 52 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 32 6pack: protocol violation 6pack: bad checksum 13 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 13 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 13 6pack: bad checksum 13 6pack: protocol violation 6pack: bad checksum f6 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 52 6pack: bad checksum 94 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 19 6pack: protocol violation 6pack: protocol violation sp1: Found TNC 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 52 6pack: protocol violation 6pack: bad checksum 52 6pack: bad checksum 13 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 34 6pack: bad checksum 19 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 19 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 19 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 32 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 32 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 32 6pack: protocol violation 6pack: protocol violation 6pack: bad checksum 1f 6pack: protocol violation 6pack: protocol violation ---[ end trace 5b6f829594578ccc ]--- 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation 6pack: protocol violation