INFO: task syz-executor871:8121 blocked for more than 140 seconds. Not tainted 4.19.211-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor871 D27504 8121 8119 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 fuse_wait_on_page_writeback fs/fuse/file.c:383 [inline] fuse_wait_on_page_writeback.isra.0+0x11b/0x170 fs/fuse/file.c:379 fuse_launder_page fs/fuse/file.c:2033 [inline] fuse_launder_page+0xb6/0xe0 fs/fuse/file.c:2026 do_launder_page mm/truncate.c:655 [inline] invalidate_inode_pages2_range+0x795/0x1110 mm/truncate.c:725 fuse_finish_open+0x2e2/0x590 fs/fuse/file.c:182 fuse_open_common+0x254/0x2c0 fs/fuse/file.c:222 do_dentry_open+0x4aa/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0x793/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f235c0c64c9 Code: Bad RIP value. RSP: 002b:00007f235c0772f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 00007f235c1574c0 RCX: 00007f235c0c64c9 RDX: 00007f235c0c64c9 RSI: 0000000000000000 RDI: 00000000200001c0 RBP: 00007f235c124164 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e R13: 00007f235c120158 R14: 00007f235c122160 R15: 00007f235c1574c8 Showing all locks held in the system: 1 lock held by khungtaskd/1559: #0: 00000000da8d2d3a (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7777: #0: 00000000e121ca08 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 2 locks held by syz-executor871/8121: #0: 000000009ea3a631 (sb_writers#11){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline] #0: 000000009ea3a631 (sb_writers#11){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360 #1: 00000000ada9d1a3 (&sb->s_type->i_mutex_key#17){+.+.}, at: inode_lock include/linux/fs.h:748 [inline] #1: 00000000ada9d1a3 (&sb->s_type->i_mutex_key#17){+.+.}, at: fuse_open_common+0x1bc/0x2c0 fs/fuse/file.c:215 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1559 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 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+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4694 Comm: systemd-journal Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:149 [inline] RIP: 0010:unwind_next_frame+0x24a/0x1400 arch/x86/kernel/unwind_orc.c:422 Code: 8d 43 ff 39 c6 0f 83 06 0e 00 00 48 b8 00 00 00 00 00 fc ff df 89 f2 48 8d 3c 95 bc 91 17 8c 48 89 f9 48 c1 e9 03 0f b6 0c 01 <48> 89 f8 83 e0 07 83 c0 03 38 c8 7c 27 84 c9 74 23 48 89 54 24 30 RSP: 0018:ffff8880a0817908 EFLAGS: 00000a06 RAX: dffffc0000000000 RBX: 1ffff11014102f2a RCX: 0000000000000000 RDX: 00000000000022ef RSI: 00000000000022ef RDI: ffffffff8c181d78 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000001 R10: ffff8880a0817b4f R11: 0000000000074071 R12: ffff8880a0817b38 R13: ffff8880a0817b25 R14: ffff8880a0817af0 R15: ffffffff8122efe1 FS: 00007f7bafb1f8c0(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7bacef0020 CR3: 00000000a1710000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __unwind_start+0x5b8/0x960 arch/x86/kernel/unwind_orc.c:667 unwind_start arch/x86/include/asm/unwind.h:60 [inline] __save_stack_trace+0x72/0x190 arch/x86/kernel/stacktrace.c:43 save_stack mm/kasan/kasan.c:448 [inline] set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:553 kmem_cache_alloc+0x122/0x370 mm/slab.c:3559 getname_flags+0xce/0x590 fs/namei.c:140 do_sys_open+0x26c/0x520 fs/open.c:1079 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f7baf0ae840 Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 RSP: 002b:00007fffe29f0168 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007fffe29f0470 RCX: 00007f7baf0ae840 RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 00005578586f3d50 RBP: 000000000000000d R08: 0000000000000000 R09: 00000000ffffffff R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff R13: 00005578586e7040 R14: 00007fffe29f0430 R15: 00005578586f2280 ---------------- Code disassembly (best guess): 0: 8d 43 ff lea -0x1(%rbx),%eax 3: 39 c6 cmp %eax,%esi 5: 0f 83 06 0e 00 00 jae 0xe11 b: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 12: fc ff df 15: 89 f2 mov %esi,%edx 17: 48 8d 3c 95 bc 91 17 lea -0x73e86e44(,%rdx,4),%rdi 1e: 8c 1f: 48 89 f9 mov %rdi,%rcx 22: 48 c1 e9 03 shr $0x3,%rcx 26: 0f b6 0c 01 movzbl (%rcx,%rax,1),%ecx * 2a: 48 89 f8 mov %rdi,%rax <-- trapping instruction 2d: 83 e0 07 and $0x7,%eax 30: 83 c0 03 add $0x3,%eax 33: 38 c8 cmp %cl,%al 35: 7c 27 jl 0x5e 37: 84 c9 test %cl,%cl 39: 74 23 je 0x5e 3b: 48 89 54 24 30 mov %rdx,0x30(%rsp)