syzbot


INFO: task hung in iterate_dir

Status: auto-closed as invalid on 2019/02/22 15:19
First crash: 2133d, last: 2133d

Sample crash report:
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
INFO: task syz-executor0:17608 blocked for more than 120 seconds.
device loop0 blocksize: 4096
      Not tainted 4.9.107-gdb2c520 #46
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
__find_get_block_slow() failed. block=1, b_blocknr=8
syz-executor0   D
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=8
29816 17608  16891 0x00000004
device loop0 blocksize: 4096
 ffff880174268000 ffff880183363480
__find_get_block_slow() failed. block=1, b_blocknr=8
 ffff880183363480b_state=0x00000029, b_size=512
 ffff8801b4bf1800device loop0 blocksize: 4096
 ffff8801db221c18 ffff8801c25f7bf0
__find_get_block_slow() failed. block=1, b_blocknr=8
 ffffffff839e8c1db_state=0x00000029, b_size=512
 ffffffff812355f7device loop0 blocksize: 4096
 0000000000000000 ffff8801742688c0
__find_get_block_slow() failed. block=1, b_blocknr=8
 0000000600000007b_state=0x00000029, b_size=512
 ffff8801db2224e8device loop0 blocksize: 4096
Call Trace:
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=8
 [<ffffffff839ea21f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3557
b_state=0x00000029, b_size=512
 [<ffffffff839f4644>] rwsem_down_read_failed+0x1e4/0x320 kernel/locking/rwsem-xadd.c:260
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
 [<ffffffff81ee8058>] call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94
device loop0 blocksize: 4096
 [<ffffffff839f3572>] __down_read arch/x86/include/asm/rwsem.h:65 [inline]
 [<ffffffff839f3572>] down_read+0x52/0xb0 kernel/locking/rwsem.c:24
__find_get_block_slow() failed. block=1, b_blocknr=8
 [<ffffffff815b3c83>] inode_lock_shared include/linux/fs.h:776 [inline]
 [<ffffffff815b3c83>] iterate_dir+0xc3/0x600 fs/readdir.c:39
b_state=0x00000029, b_size=512
 [<ffffffff815b5047>] SYSC_getdents64 fs/readdir.c:313 [inline]
 [<ffffffff815b5047>] SyS_getdents64+0x137/0x280 fs/readdir.c:294
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
device loop0 blocksize: 4096
 [<ffffffff839f9b13>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
__find_get_block_slow() failed. block=1, b_blocknr=8

Showing all locks held in the system:
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
2 locks held by khungtaskd/519:
 #0: 
__find_get_block_slow() failed. block=1, b_blocknr=8
 (b_state=0x00000029, b_size=512
rcu_read_lockdevice loop0 blocksize: 4096
){......}, at: [<ffffffff8136662c>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
){......}, at: [<ffffffff8136662c>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1: 
b_state=0x00000029, b_size=512
 (device loop0 blocksize: 4096
tasklist_lock){.+.?..}, at: [<ffffffff81425cb7>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
1 lock held by rsyslogd/3676:
 #0: 
__find_get_block_slow() failed. block=1, b_blocknr=8
 (b_state=0x00000029, b_size=512
&f->f_pos_lockdevice loop0 blocksize: 4096
){+.+.+.}, at: [<ffffffff815d7fac>] __fdget_pos+0xac/0xd0 fs/file.c:781
2 locks held by getty/3772:
b_state=0x00000029, b_size=512
 #0: 
device loop0 blocksize: 4096
 (&tty->ldisc_sem){++++++}, at: [<ffffffff839f7cc2>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1: 
b_state=0x00000029, b_size=512
 (device loop0 blocksize: 4096
&ldata->atomic_read_lock){+.+...}, at: [<ffffffff8211fc62>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2133
b_state=0x00000029, b_size=512
2 locks held by syz-executor0/17608:
device loop0 blocksize: 4096
 #0:  (&f->f_pos_lock){+.+.+.}
__find_get_block_slow() failed. block=1, b_blocknr=8
, at: [<ffffffff815d7fac>] __fdget_pos+0xac/0xd0 fs/file.c:781
 #1: 
device loop0 blocksize: 4096
 (&sb->s_type->i_mutex_key#16){++++++}__find_get_block_slow() failed. block=1, b_blocknr=8
, at: [<ffffffff815b3c83>] inode_lock_shared include/linux/fs.h:776 [inline]
, at: [<ffffffff815b3c83>] iterate_dir+0xc3/0x600 fs/readdir.c:39
2 locks held by syz-executor0/17616:
device loop0 blocksize: 4096
 #0:  (sb_writers#13
__find_get_block_slow() failed. block=1, b_blocknr=8
){.+.+.+}b_state=0x00000029, b_size=512
, at: [<ffffffff815e084f>] sb_start_write include/linux/fs.h:1573 [inline]
, at: [<ffffffff815e084f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&sb->s_type->i_mutex_key#16
__find_get_block_slow() failed. block=1, b_blocknr=8
/1b_state=0x00000029, b_size=512
){+.+.+.}device loop0 blocksize: 4096
, at: [<ffffffff815a9e3a>] inode_lock_nested include/linux/fs.h:801 [inline]
, at: [<ffffffff815a9e3a>] filename_create+0x17a/0x490 fs/namei.c:3639

b_state=0x00000029, b_size=512
=============================================

device loop0 blocksize: 4096
NMI backtrace for cpu 0
CPU: 0 PID: 519 Comm: khungtaskd Not tainted 4.9.107-gdb2c520 #46
__find_get_block_slow() failed. block=1, b_blocknr=8
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d85efd08
b_state=0x00000029, b_size=512
 ffffffff81eb3da9device loop0 blocksize: 4096
 0000000000000000 0000000000000000
 0000000000000000
b_state=0x00000029, b_size=512
 0000000000000001device loop0 blocksize: 4096
 ffffffff810b96a0 ffff8801d85efd40
 ffffffff81ebf0a7
b_state=0x00000029, b_size=512
 0000000000000000device loop0 blocksize: 4096
 0000000000000000 0000000000000003
__find_get_block_slow() failed. block=1, b_blocknr=8
 [<ffffffff81eb3da9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb3da9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
 [<ffffffff81ebf0a7>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
 [<ffffffff81ebf03a>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
device loop0 blocksize: 4096
 [<ffffffff810b97a4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
__find_get_block_slow() failed. block=1, b_blocknr=8
 [<ffffffff81366bc4>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81366bc4>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81366bc4>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81366bc4>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
 [<ffffffff8119d04d>] kthread+0x26d/0x300 kernel/kthread.c:211
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
 [<ffffffff839f9cdc>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
device loop0 blocksize: 4096
Sending NMI from CPU 0 to CPUs 1:
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
NMI backtrace for cpu 1
CPU: 1 PID: 17577 Comm: syz-executor0 Not tainted 4.9.107-gdb2c520 #46
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801b4bf1800 task.stack: ffff880173e50000
RIP: 0010:[<ffffffff8135e98b>] c [<ffffffff8135e98b>] __write_once_size include/linux/compiler.h:272 [inline]
RIP: 0010:[<ffffffff8135e98b>] c [<ffffffff8135e98b>] __sanitizer_cov_trace_pc+0x4b/0x50 kernel/kcov.c:108
RSP: 0018:ffff880173e57268  EFLAGS: 00000046
RAX: 0000000000040000 RBX: ffff880173e572f0 RCX: ffffc900116b7000
RDX: 0000000000040000 RSI: ffffffff81ed3df2 RDI: ffff880173e572f5
RBP: ffff880173e57268 R08: fffffbfff0b5d8d6 R09: fffffbfff0b5d8d4
R10: fffffbfff0b5d8d5 R11: ffffffff85aec6a9 R12: ffffffff85aec6aa
R13: ffff880173e57450 R14: 0000000000000030 R15: 0000000000000010
FS:  00007f2012dc2700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c420dad000 CR3: 00000001b6d64000 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff880173e57398c ffffffff81ed3df2c 0000000000000025c ffff880173e57370c
 ffffffff83cceaa9c 20ff8801cbf63f40c 1ffff1002e7cae5ac ffffffff00000000c
 1000881000000008c 0000000000000029c ffff880173e57410c 0000080900000000c
Call Trace:
 [<ffffffff81ed3df2>] number+0x1d2/0xa80 lib/vsprintf.c:417
 [<ffffffff81ee007a>] vsnprintf+0x118a/0x1840 lib/vsprintf.c:2110
 [<ffffffff81ee075d>] vscnprintf+0x2d/0x60 lib/vsprintf.c:2147
 [<ffffffff8125f264>] vprintk_emit+0xf4/0x790 kernel/printk/printk.c:1847
 [<ffffffff8125f928>] vprintk+0x28/0x30 kernel/printk/printk.c:1913
 [<ffffffff8125f94d>] vprintk_default+0x1d/0x30 kernel/printk/printk.c:1914
 [<ffffffff8142ca8c>] vprintk_func kernel/printk/internal.h:36 [inline]
 [<ffffffff8142ca8c>] printk+0xaf/0xd7 kernel/printk/printk.c:1975
 [<ffffffff81cba355>] __find_get_block_slow.cold.57+0x82/0xf0 fs/buffer.c:242
 [<ffffffff8162434e>] __find_get_block+0x23e/0x4c0 fs/buffer.c:1360
 [<ffffffff81625159>] __getblk_slow fs/buffer.c:1101 [inline]
 [<ffffffff81625159>] __getblk_gfp+0x189/0x710 fs/buffer.c:1386
 [<ffffffff81628afd>] __bread_gfp+0x2d/0x270 fs/buffer.c:1420
 [<ffffffff818b6d28>] sb_bread include/linux/buffer_head.h:300 [inline]
 [<ffffffff818b6d28>] fat__get_entry+0x4c8/0x8f0 fs/fat/dir.c:100
 [<ffffffff818beb27>] fat_get_entry fs/fat/dir.c:128 [inline]
 [<ffffffff818beb27>] fat_search_long+0x277/0x1180 fs/fat/dir.c:477
 [<ffffffff818d8fb4>] vfat_find+0x134/0x180 fs/fat/namei_vfat.c:708
 [<ffffffff818d9791>] vfat_lookup+0xe1/0x530 fs/fat/namei_vfat.c:731
 [<ffffffff81593c6c>] lookup_real fs/namei.c:1522 [inline]
 [<ffffffff81593c6c>] __lookup_hash+0x11c/0x190 fs/namei.c:1542
 [<ffffffff815a9e66>] filename_create+0x1a6/0x490 fs/namei.c:3640
 [<ffffffff815abb45>] user_path_create fs/namei.c:3697 [inline]
 [<ffffffff815abb45>] SYSC_mknodat fs/namei.c:3764 [inline]
 [<ffffffff815abb45>] SyS_mknodat+0x195/0x430 fs/namei.c:3752
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f9b13>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: c8b c90 c80 c12 c00 c00 c83 cfa c02 c75 c20 c48 c8b c88 c88 c12 c00 c00 c8b c80 c84 c12 c00 c00 c48 c8b c11 c48 c83 cc2 c01 c48 c39 cd0 c76 c07 c48 c89 c34 cd1 c48 c89 c11 c<5d> cc3 c0f c1f c00 c55 c48 c89 ce5 c41 c57 c41 c56 c41 c55 c41 c54 c53 c48 c89 cf3 c
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/06/11 06:51 https://android.googlesource.com/kernel/common android-4.9 db2c520bb56b 866118af .config console log report ci-android-49-kasan-gce-root
* Struck through repros no longer work on HEAD.