audit: type=1400 audit(1601357270.954:8): avc: denied { execmem } for pid=6396 comm="syz-executor010" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1 EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue INFO: task syz-executor010:6397 blocked for more than 140 seconds. Not tainted 4.14.198-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor010 D27160 6397 6396 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 io_schedule+0xb5/0x120 kernel/sched/core.c:5036 bit_wait_io+0x12/0x90 kernel/sched/wait_bit.c:249 __wait_on_bit_lock+0xc2/0x1d0 kernel/sched/wait_bit.c:89 out_of_line_wait_on_bit_lock+0xbc/0xd0 kernel/sched/wait_bit.c:116 wait_on_bit_lock_io include/linux/wait_bit.h:213 [inline] __lock_buffer+0x43/0x50 fs/buffer.c:72 lock_buffer include/linux/buffer_head.h:374 [inline] __sync_dirty_buffer+0x214/0x290 fs/buffer.c:3251 __ext4_handle_dirty_metadata+0x169/0x480 fs/ext4/ext4_jbd2.c:300 ext4_convert_inline_data_nolock+0x4ce/0xb40 fs/ext4/inline.c:1246 ext4_convert_inline_data+0x2ae/0x2fc fs/ext4/inline.c:2000 ext4_fallocate+0x106/0x1d80 fs/ext4/extents.c:4968 vfs_fallocate+0x346/0x790 fs/open.c:319 SYSC_fallocate fs/open.c:342 [inline] SyS_fallocate+0x4a/0x80 fs/open.c:336 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x445489 RSP: 002b:00007ffebbb4f898 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000445489 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00000000006d1018 R08: 0000000000000001 R09: 0000000000000001 R10: 000000000000ffe0 R11: 0000000000000246 R12: 00000000004025f0 R13: 0000000000402680 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/1068: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 2 locks held by syz-executor010/6397: #0: (sb_writers#3){.+.+}, at: [] file_start_write include/linux/fs.h:2712 [inline] #0: (sb_writers#3){.+.+}, at: [] vfs_fallocate+0x5c1/0x790 fs/open.c:318 #1: (&ei->xattr_sem){++++}, at: [] ext4_write_lock_xattr fs/ext4/xattr.h:141 [inline] #1: (&ei->xattr_sem){++++}, at: [] ext4_convert_inline_data+0x19d/0x2fc fs/ext4/inline.c:1998 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1068 Comm: khungtaskd Not tainted 4.14.198-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x283 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x17f lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5b9/0xb40 kernel/hung_task.c:274 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at pc 0xffffffff8655830e