Hello, syzbot found the following issue on: HEAD commit: 4b358aabb93a Add linux-next specific files for 20210813 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=1603f181300000 kernel config: https://syzkaller.appspot.com/x/.config?x=b99612666fbe2d6a dashboard link: https://syzkaller.appspot.com/bug?extid=7d51f807c81b190a127d compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.1 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+7d51f807c81b190a127d@xxxxxxxxxxxxxxxxxxxxxxxxx INFO: task syz-executor.4:21120 can't die for more than 143 seconds. task:syz-executor.4 state:D stack:28448 pid:21120 ppid: 6572 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4711 [inline] __schedule+0x93a/0x26f0 kernel/sched/core.c:5966 schedule+0xd3/0x270 kernel/sched/core.c:6045 __lock_sock+0x13d/0x260 net/core/sock.c:2645 lock_sock_nested+0xf6/0x120 net/core/sock.c:3178 lock_sock include/net/sock.h:1612 [inline] bt_sock_wait_state+0x249/0x590 net/bluetooth/af_bluetooth.c:557 rfcomm_sock_connect+0x3a5/0x460 net/bluetooth/rfcomm/sock.c:416 __sys_connect_file+0x155/0x1a0 net/socket.c:1890 __sys_connect+0x161/0x190 net/socket.c:1907 __do_sys_connect net/socket.c:1917 [inline] __se_sys_connect net/socket.c:1914 [inline] __x64_sys_connect+0x6f/0xb0 net/socket.c:1914 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665e9 RSP: 002b:00007fa7b02bf188 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665e9 RDX: 0000000000000080 RSI: 0000000020000000 RDI: 0000000000000004 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007fffd83567bf R14: 00007fa7b02bf300 R15: 0000000000022000 INFO: task syz-executor.4:21120 blocked for more than 143 seconds. Not tainted 5.14.0-rc5-next-20210813-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:28448 pid:21120 ppid: 6572 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4711 [inline] __schedule+0x93a/0x26f0 kernel/sched/core.c:5966 schedule+0xd3/0x270 kernel/sched/core.c:6045 __lock_sock+0x13d/0x260 net/core/sock.c:2645 lock_sock_nested+0xf6/0x120 net/core/sock.c:3178 lock_sock include/net/sock.h:1612 [inline] bt_sock_wait_state+0x249/0x590 net/bluetooth/af_bluetooth.c:557 rfcomm_sock_connect+0x3a5/0x460 net/bluetooth/rfcomm/sock.c:416 __sys_connect_file+0x155/0x1a0 net/socket.c:1890 __sys_connect+0x161/0x190 net/socket.c:1907 __do_sys_connect net/socket.c:1917 [inline] __se_sys_connect net/socket.c:1914 [inline] __x64_sys_connect+0x6f/0xb0 net/socket.c:1914 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665e9 RSP: 002b:00007fa7b02bf188 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665e9 RDX: 0000000000000080 RSI: 0000000020000000 RDI: 0000000000000004 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007fffd83567bf R14: 00007fa7b02bf300 R15: 0000000000022000 INFO: task syz-executor.4:21124 can't die for more than 143 seconds. task:syz-executor.4 state:D stack:29104 pid:21124 ppid: 6572 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:4711 [inline] __schedule+0x93a/0x26f0 kernel/sched/core.c:5966 schedule+0xd3/0x270 kernel/sched/core.c:6045 __lock_sock+0x13d/0x260 net/core/sock.c:2645 lock_sock_nested+0xf6/0x120 net/core/sock.c:3178 lock_sock include/net/sock.h:1612 [inline] rfcomm_sk_state_change+0xb4/0x390 net/bluetooth/rfcomm/sock.c:73 __rfcomm_dlc_close+0x1b6/0x8a0 net/bluetooth/rfcomm/core.c:489 rfcomm_dlc_close+0x1ea/0x240 net/bluetooth/rfcomm/core.c:520 __rfcomm_sock_close+0xac/0x260 net/bluetooth/rfcomm/sock.c:220 rfcomm_sock_shutdown+0xe9/0x210 net/bluetooth/rfcomm/sock.c:931 __sys_shutdown_sock net/socket.c:2242 [inline] __sys_shutdown_sock net/socket.c:2236 [inline] __sys_shutdown+0xf1/0x1b0 net/socket.c:2254 __do_sys_shutdown net/socket.c:2262 [inline] __se_sys_shutdown net/socket.c:2260 [inline] __x64_sys_shutdown+0x50/0x70 net/socket.c:2260 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665e9 RSP: 002b:00007fa7b029e188 EFLAGS: 00000246 ORIG_RAX: 0000000000000030 RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665e9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038 R13: 00007fffd83567bf R14: 00007fa7b029e300 R15: 0000000000022000 INFO: task syz-executor.4:21124 blocked for more than 143 seconds. Not tainted 5.14.0-rc5-next-20210813-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:29104 pid:21124 ppid: 6572 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:4711 [inline] __schedule+0x93a/0x26f0 kernel/sched/core.c:5966 schedule+0xd3/0x270 kernel/sched/core.c:6045 __lock_sock+0x13d/0x260 net/core/sock.c:2645 lock_sock_nested+0xf6/0x120 net/core/sock.c:3178 lock_sock include/net/sock.h:1612 [inline] rfcomm_sk_state_change+0xb4/0x390 net/bluetooth/rfcomm/sock.c:73 __rfcomm_dlc_close+0x1b6/0x8a0 net/bluetooth/rfcomm/core.c:489 rfcomm_dlc_close+0x1ea/0x240 net/bluetooth/rfcomm/core.c:520 __rfcomm_sock_close+0xac/0x260 net/bluetooth/rfcomm/sock.c:220 rfcomm_sock_shutdown+0xe9/0x210 net/bluetooth/rfcomm/sock.c:931 __sys_shutdown_sock net/socket.c:2242 [inline] __sys_shutdown_sock net/socket.c:2236 [inline] __sys_shutdown+0xf1/0x1b0 net/socket.c:2254 __do_sys_shutdown net/socket.c:2262 [inline] __se_sys_shutdown net/socket.c:2260 [inline] __x64_sys_shutdown+0x50/0x70 net/socket.c:2260 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665e9 RSP: 002b:00007fa7b029e188 EFLAGS: 00000246 ORIG_RAX: 0000000000000030 RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665e9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038 R13: 00007fffd83567bf R14: 00007fa7b029e300 R15: 0000000000022000 INFO: lockdep is turned off. NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.14.0-rc5-next-20210813-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:254 [inline] watchdog+0xcb7/0xed0 kernel/hung_task.c:339 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 6267 Comm: in:imklog Not tainted 5.14.0-rc5-next-20210813-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__sanitizer_cov_trace_pc+0x37/0x60 kernel/kcov.c:197 Code: 81 e1 00 01 00 00 65 48 8b 14 25 40 f0 01 00 a9 00 01 ff 00 74 0e 85 c9 74 35 8b 82 3c 15 00 00 85 c0 74 2b 8b 82 18 15 00 00 <83> f8 02 75 20 48 8b 8a 20 15 00 00 8b 92 1c 15 00 00 48 8b 01 48 RSP: 0018:ffffc9000c577648 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff8880775b9c80 RSI: ffffffff83f260b5 RDI: 0000000000000003 RBP: 0000000000000000 R08: 000000000000002f R09: 0000000000000000 R10: ffffffff83f26037 R11: 0000000000000000 R12: 0000000000000004 R13: ffffffff898ca243 R14: ffffc9008c577a4f R15: ffffc9000c577a51 FS: 00007f9245542700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9a4b72b008 CR3: 000000006fe68000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: number+0x205/0xae0 lib/vsprintf.c:490 vsnprintf+0xf09/0x14f0 lib/vsprintf.c:2875 sprintf+0xc0/0x100 lib/vsprintf.c:3011 print_syslog kernel/printk/printk.c:1257 [inline] info_print_prefix+0x2d5/0x340 kernel/printk/printk.c:1287 record_print_text+0x14d/0x3e0 kernel/printk/printk.c:1339 syslog_print+0x48c/0x580 kernel/printk/printk.c:1539 do_syslog.part.0+0x202/0x640 kernel/printk/printk.c:1658 do_syslog+0x49/0x60 kernel/printk/printk.c:1643 kmsg_read+0x90/0xb0 fs/proc/kmsg.c:40 pde_read fs/proc/inode.c:311 [inline] proc_reg_read+0x119/0x300 fs/proc/inode.c:321 vfs_read+0x1b5/0x600 fs/read_write.c:494 ksys_read+0x12d/0x250 fs/read_write.c:634 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f9247b8522d Code: c1 20 00 00 75 10 b8 00 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 4e fc ff ff 48 89 04 24 b8 00 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 97 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007f9245521580 EFLAGS: 00000293 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f9247b8522d RDX: 0000000000001fa0 RSI: 00007f9245521da0 RDI: 0000000000000004 RBP: 000055eb855a59d0 R08: 0000000000000000 R09: 0000000004000001 R10: 0000000000000001 R11: 0000000000000293 R12: 00007f9245521da0 R13: 0000000000001fa0 R14: 0000000000001f9f R15: 00007f9245521dd7 ---------------- Code disassembly (best guess): 0: 81 e1 00 01 00 00 and $0x100,%ecx 6: 65 48 8b 14 25 40 f0 mov %gs:0x1f040,%rdx d: 01 00 f: a9 00 01 ff 00 test $0xff0100,%eax 14: 74 0e je 0x24 16: 85 c9 test %ecx,%ecx 18: 74 35 je 0x4f 1a: 8b 82 3c 15 00 00 mov 0x153c(%rdx),%eax 20: 85 c0 test %eax,%eax 22: 74 2b je 0x4f 24: 8b 82 18 15 00 00 mov 0x1518(%rdx),%eax 2a: 83 f8 02 cmp $0x2,%eax <-- trapping instruction 2d: 75 20 jne 0x4f 2f: 48 8b 8a 20 15 00 00 mov 0x1520(%rdx),%rcx 36: 8b 92 1c 15 00 00 mov 0x151c(%rdx),%edx 3c: 48 8b 01 mov (%rcx),%rax 3f: 48 rex.W --- This report is generated by a bot. 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