attempt to access beyond end of device loop0: rw=0, want=18442984958116442986, limit=16203 INFO: task syz-executor5:3889 blocked for more than 140 seconds. Not tainted 4.9.124-g09eb2ba #31 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor5 D27864 3889 1 0x00000004 ffff8801d95cc800 0000000000000000 ffff8801b7f2b480 ffff8801d9a6b000 ffff8801db321c18 ffff88019e21f4e0 ffffffff839f0afd ffffffff81237da7 0000000000000000 ffff8801d95cd0c0 0000000600000007 ffff8801db3224e8 Call Trace: [] schedule+0x7f/0x1b0 kernel/sched/core.c:3553 [] rwsem_down_read_failed+0x1e4/0x320 kernel/locking/rwsem-xadd.c:260 [] call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94 [] __down_read arch/x86/include/asm/rwsem.h:65 [inline] [] down_read+0x52/0xb0 kernel/locking/rwsem.c:24 [] inode_lock_shared include/linux/fs.h:776 [inline] [] lookup_slow+0x141/0x470 fs/namei.c:1645 [] walk_component+0x716/0x1bb0 fs/namei.c:1784 [] link_path_walk+0x889/0x1200 fs/namei.c:2120 [] path_openat+0x1ad/0x3590 fs/namei.c:3533 [] do_filp_open+0x197/0x270 fs/namei.c:3568 [] do_sys_open+0x30d/0x5c0 fs/open.c:1072 [] SYSC_open fs/open.c:1090 [inline] [] SyS_open+0x2d/0x40 fs/open.c:1085 [] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282 [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb Showing all locks held in the system: 2 locks held by khungtaskd/519: #0: (rcu_read_lock){......}, at: [] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline] #0: (rcu_read_lock){......}, at: [] watchdog+0x11c/0xa20 kernel/hung_task.c:239 #1: (tasklist_lock){.+.+..}, at: [] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336 2 locks held by getty/3780: #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142 1 lock held by syz-executor5/3889: #0: (&sb->s_type->i_mutex_key#26){++++++}, at: [] inode_lock_shared include/linux/fs.h:776 [inline] #0: (&sb->s_type->i_mutex_key#26){++++++}, at: [] lookup_slow+0x141/0x470 fs/namei.c:1645 2 locks held by syz-executor5/16196: #0: (sb_writers#10){.+.+.+}, at: [] sb_start_write include/linux/fs.h:1573 [inline] #0: (sb_writers#10){.+.+.+}, at: [] mnt_want_write+0x3f/0xb0 fs/namespace.c:391 #1: (&sb->s_type->i_mutex_key#26){++++++}, at: [] inode_lock include/linux/fs.h:766 [inline] #1: (&sb->s_type->i_mutex_key#26){++++++}, at: [] do_last fs/namei.c:3312 [inline] #1: (&sb->s_type->i_mutex_key#26){++++++}, at: [] path_openat+0xed5/0x3590 fs/namei.c:3534 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 519 Comm: khungtaskd Not tainted 4.9.124-g09eb2ba #31 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801d85d7d08 ffffffff81eb95e9 0000000000000000 0000000000000001 0000000000000001 0000000000000001 ffffffff810b9fa0 ffff8801d85d7d40 ffffffff81ec4927 0000000000000001 0000000000000000 0000000000000003 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99 [] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60 [] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37 [] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline] [] check_hung_task kernel/hung_task.c:125 [inline] [] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline] [] watchdog+0x6b4/0xa20 kernel/hung_task.c:239 [] kthread+0x26d/0x300 kernel/kthread.c:211 [] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 16180 Comm: syz-executor5 Not tainted 4.9.124-g09eb2ba #31 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff88019a81c800 task.stack: ffff8801999e8000 RIP: 0010:[] c [] check_kcov_mode kernel/kcov.c:66 [inline] RIP: 0010:[] c [] __sanitizer_cov_trace_pc+0x1a/0x50 kernel/kcov.c:100 RSP: 0018:ffff8801999ef250 EFLAGS: 00000246 RAX: ffff88019a81c800 RBX: ffffea0006d0f8c0 RCX: ffffc900076e9000 RDX: 0000000000000000 RSI: ffffffff8143c51b RDI: 0000000000000246 RBP: ffff8801999ef250 R08: ffff88019a81d160 R09: 0000000000000001 R10: 0000000000000000 R11: 1ffff10033503a27 R12: 0000000000000007 R13: dffffc0000000000 R14: 0000000002420848 R15: ffff8801d5d46548 FS: 00007f9ed8379700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000014f8000 CR3: 00000001cee70000 CR4: 00000000001606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: ffff8801999ef2a8c ffffffff8143c529c ffffffff81628cbac 0000020006d0f8c0c fffffbfff098c560c 0000000000000008c 0000000000000003c ffffea0006d0f8dcc ffff8801d5d46548c 0000000000000200c dffffc0000000000c ffff8801999ef348c Call Trace: [] pagecache_get_page+0x69/0x720 mm/filemap.c:1207 [] find_or_create_page include/linux/pagemap.h:309 [inline] [] grow_dev_page fs/buffer.c:1005 [inline] [] grow_buffers fs/buffer.c:1078 [inline] [] __getblk_slow fs/buffer.c:1105 [inline] [] __getblk_gfp+0x249/0x710 fs/buffer.c:1386 [] __bread_gfp+0x2d/0x270 fs/buffer.c:1420 [] sb_bread include/linux/buffer_head.h:300 [inline] [] fat__get_entry+0x4c8/0x8f0 fs/fat/dir.c:100 [] fat_get_entry fs/fat/dir.c:128 [inline] [] fat_search_long+0x277/0x1180 fs/fat/dir.c:477 [] vfat_find+0x134/0x180 fs/fat/namei_vfat.c:708 [] vfat_lookup+0xe1/0x530 fs/fat/namei_vfat.c:731 [] lookup_open+0x63d/0x1930 fs/namei.c:3203 [] do_last fs/namei.c:3315 [inline] [] path_openat+0xef8/0x3590 fs/namei.c:3534 [] do_filp_open+0x197/0x270 fs/namei.c:3568 [] do_sys_open+0x30d/0x5c0 fs/open.c:1072 [] SYSC_openat fs/open.c:1099 [inline] [] SyS_openat+0x30/0x40 fs/open.c:1093 [] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282 [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb Code: cf9 cfe cff cff c66 c2e c0f c1f c84 c00 c00 c00 c00 c00 c0f c1f c00 c55 c48 c89 ce5 c65 c48 c8b c04 c25 cc0 c7d c01 c00 c65 c8b c15 c4c c70 ccb c7e c81 ce2 c00 c01 c1f c00 c<48> c8b c75 c08 c75 c2b c8b c90 c80 c12 c00 c00 c83 cfa c02 c75 c20 c48 c8b c88 c88 c