Hello, When using Healer to fuzz the latest Linux kernel, the following crash was triggered. HEAD commit: 7d2a07b76933 Linux 5.14 git tree: upstream console output: https://drive.google.com/file/d/15bKzfm25-e8kS5RDgiqoT024VpaOBhju/view?usp=sharing kernel config: https://drive.google.com/file/d/1XD9WYDViQLSXN7RGwH8AGGDvP9JvOghx/view?usp=sharing Similar bug reported by Syzbot: https://syzkaller.appspot.com/bug?id=9b6cad151b16cc24fe15fc086a3e53c0a3b2a43c Sorry, I don't have a reproducer for this crash, hope the symbolized report can help. If you fix this issue, please add the following tag to the commit: Reported-by: Hao Sun <sunhao.th@xxxxxxxxx> INFO: task syz-executor:10684 blocked for more than 143 seconds. Not tainted 5.14.0 #25 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:27880 pid:10684 ppid: 9037 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4695 [inline] __schedule+0x974/0x2510 kernel/sched/core.c:6026 schedule+0xd3/0x270 kernel/sched/core.c:6105 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6164 __mutex_lock_common kernel/locking/mutex.c:1036 [inline] __mutex_lock+0x92e/0x1390 kernel/locking/mutex.c:1104 blkdev_put+0x98/0x720 fs/block_dev.c:1534 blkdev_close+0x8c/0xb0 fs/block_dev.c:1586 __fput+0x288/0x920 fs/file_table.c:280 task_work_run+0xe0/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x28d/0x2a0 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4739cd RSP: 002b:00007f1d42ba6198 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 000000000059c0a0 RCX: 00000000004739cd RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 00000000004ebd80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000059c0a0 R13: 00007fffd3a7039f R14: 00007fffd3a70540 R15: 00007f1d42ba6300 INFO: task syz-executor:10690 blocked for more than 143 seconds. Not tainted 5.14.0 #25 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:27456 pid:10690 ppid: 9037 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4695 [inline] __schedule+0x974/0x2510 kernel/sched/core.c:6026 schedule+0xd3/0x270 kernel/sched/core.c:6105 io_schedule+0x17/0x70 kernel/sched/core.c:8076 bit_wait_io+0x12/0xd0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x60/0x190 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0xd5/0x110 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] __wait_on_buffer fs/buffer.c:122 [inline] wait_on_buffer include/linux/buffer_head.h:356 [inline] __block_write_begin_int+0x944/0x1f00 fs/buffer.c:2044 __block_write_begin fs/buffer.c:2056 [inline] block_write_begin+0x58/0x2e0 fs/buffer.c:2116 generic_perform_write+0x1fe/0x510 mm/filemap.c:3656 __generic_file_write_iter+0x24e/0x610 mm/filemap.c:3783 blkdev_write_iter+0x2a3/0x560 fs/block_dev.c:1645 call_write_iter include/linux/fs.h:2114 [inline] new_sync_write+0x42f/0x660 fs/read_write.c:518 vfs_write+0x67a/0xa50 fs/read_write.c:605 ksys_write+0x12d/0x250 fs/read_write.c:658 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: 0033:0x4739cd RSP: 002b:00007f1d42b85198 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000059c158 RCX: 00000000004739cd RDX: 0000000000000078 RSI: 00000000200000c0 RDI: 0000000000000006 RBP: 00000000004ebd80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000059c158 R13: 00007fffd3a7039f R14: 00007fffd3a70540 R15: 00007f1d42b85300 INFO: task syz-executor:10693 blocked for more than 143 seconds. Not tainted 5.14.0 #25 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:28400 pid:10693 ppid: 9037 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4695 [inline] __schedule+0x974/0x2510 kernel/sched/core.c:6026 schedule+0xd3/0x270 kernel/sched/core.c:6105 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6164 __mutex_lock_common kernel/locking/mutex.c:1036 [inline] __mutex_lock+0x92e/0x1390 kernel/locking/mutex.c:1104 blkdev_get_by_dev fs/block_dev.c:1410 [inline] blkdev_get_by_dev+0x457/0xb80 fs/block_dev.c:1383 blkdev_open+0x154/0x2b0 fs/block_dev.c:1512 do_dentry_open+0x4c8/0x11d0 fs/open.c:826 do_open fs/namei.c:3374 [inline] path_openat+0x1bf9/0x27a0 fs/namei.c:3507 do_filp_open+0x1c1/0x290 fs/namei.c:3534 do_sys_openat2+0x61b/0x8f0 fs/open.c:1204 do_sys_open+0xc3/0x140 fs/open.c:1220 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: 0033:0x41a334 RSP: 002b:00007f1d42b63cc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 000000000041a334 RDX: 0000000000000000 RSI: 00007f1d42b63d60 RDI: 00000000ffffff9c RBP: 00007f1d42b63d60 R08: 0000000000000000 R09: 002364626e2f7665 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007fffd3a7039f R14: 00007fffd3a70540 R15: 00007f1d42b64300 INFO: task systemd-udevd:10692 blocked for more than 143 seconds. Not tainted 5.14.0 #25 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:systemd-udevd state:D stack:27640 pid:10692 ppid: 4542 flags:0x00004220 Call Trace: context_switch kernel/sched/core.c:4695 [inline] __schedule+0x974/0x2510 kernel/sched/core.c:6026 schedule+0xd3/0x270 kernel/sched/core.c:6105 io_schedule+0x17/0x70 kernel/sched/core.c:8076 wait_on_page_bit_common+0x57c/0xf10 mm/filemap.c:1301 wait_on_page_bit mm/filemap.c:1362 [inline] wait_on_page_locked include/linux/pagemap.h:689 [inline] do_read_cache_page+0x26d/0x1440 mm/filemap.c:3394 read_mapping_page include/linux/pagemap.h:515 [inline] read_part_sector+0x146/0x670 block/partitions/core.c:726 adfspart_check_ICS+0x9d/0xc90 block/partitions/acorn.c:360 check_partition block/partitions/core.c:147 [inline] blk_add_partitions block/partitions/core.c:611 [inline] bdev_disk_changed block/partitions/core.c:697 [inline] bdev_disk_changed+0x753/0x1130 block/partitions/core.c:664 blkdev_get_whole+0x216/0x3f0 fs/block_dev.c:1269 blkdev_get_by_dev fs/block_dev.c:1417 [inline] blkdev_get_by_dev+0x4c0/0xb80 fs/block_dev.c:1383 blkdev_open+0x154/0x2b0 fs/block_dev.c:1512 do_dentry_open+0x4c8/0x11d0 fs/open.c:826 do_open fs/namei.c:3374 [inline] path_openat+0x1bf9/0x27a0 fs/namei.c:3507 do_filp_open+0x1c1/0x290 fs/namei.c:3534 do_sys_openat2+0x61b/0x8f0 fs/open.c:1204 do_sys_open+0xc3/0x140 fs/open.c:1220 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: 0033:0x7f5595f12840 RSP: 002b:00007ffd28c6bbb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000055f37228aa00 RCX: 00007f5595f12840 RDX: 000055f371560fe3 RSI: 00000000000a0800 RDI: 000055f372286c80 RBP: 00007ffd28c6bd30 R08: 000055f371560670 R09: 0000000000000010 R10: 000055f371560d0c R11: 0000000000000246 R12: 00007ffd28c6bc80 R13: 000055f3722878f0 R14: 0000000000000003 R15: 000000000000000e Showing all locks held in the system: 1 lock held by khungtaskd/1630: #0: ffffffff8b979b80 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 1 lock held by in:imklog/7561: #0: ffff888101e1dc70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:974 2 locks held by agetty/7569: #0: ffff888108bbf098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffffc900002a42e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x8db/0x1250 drivers/tty/n_tty.c:2113 1 lock held by syz-executor/10684: #0: ffff888100c14d18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x98/0x720 fs/block_dev.c:1534 1 lock held by syz-executor/10693: #0: ffff888100c14d18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev fs/block_dev.c:1410 [inline] #0: ffff888100c14d18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x457/0xb80 fs/block_dev.c:1383 1 lock held by systemd-udevd/10692: #0: ffff888100c14d18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev fs/block_dev.c:1410 [inline] #0: ffff888100c14d18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x457/0xb80 fs/block_dev.c:1383 1 lock held by syz-executor/11137: #0: ffff888100c14d18 (&disk->open_mutex){+.+.}-{3:3}, at: iterate_bdevs+0xe0/0x2d0 fs/block_dev.c:1869 1 lock held by syz-executor/11425: #0: ffff888100c14d18 (&disk->open_mutex){+.+.}-{3:3}, at: iterate_bdevs+0xe0/0x2d0 fs/block_dev.c:1869 1 lock held by syz-executor/11428: #0: ffff888100c14d18 (&disk->open_mutex){+.+.}-{3:3}, at: iterate_bdevs+0xe0/0x2d0 fs/block_dev.c:1869 1 lock held by syz-executor/11843: #0: ffff888100c14d18 (&disk->open_mutex){+.+.}-{3:3}, at: iterate_bdevs+0xe0/0x2d0 fs/block_dev.c:1869 1 lock held by syz-executor/12538: #0: ffff888100c14d18 (&disk->open_mutex){+.+.}-{3:3}, at: iterate_bdevs+0xe0/0x2d0 fs/block_dev.c:1869 1 lock held by syz-executor/12540: #0: ffff888100c14d18 (&disk->open_mutex){+.+.}-{3:3}, at: iterate_bdevs+0xe0/0x2d0 fs/block_dev.c:1869
