syzbot


INFO: task hung in process_measurement (3)

Status: upstream: reported on 2025/11/13 09:59
Reported-by: syzbot+4e93a2dbb33785540085@syzkaller.appspotmail.com
First crash: 8d02h, last: 8d02h
Similar bugs (12)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: task hung in process_measurement (2) 1 1 315d 315d 0/3 auto-obsoleted due to no activity on 2025/04/20 01:13
linux-5.15 INFO: task hung in process_measurement (3) origin:lts-only 1 C 2 28d 198d 0/3 upstream: reported C repro on 2025/05/07 00:26
linux-5.15 INFO: task hung in process_measurement 1 1 852d 852d 0/3 auto-obsoleted due to no activity on 2023/10/31 09:35
upstream INFO: task hung in process_measurement (3) integrity lsm 1 C done 49 2d22h 183d 0/29 upstream: reported C repro on 2025/05/21 17:47
linux-4.19 INFO: task hung in process_measurement 1 2 2182d 2258d 0/1 auto-closed as invalid on 2020/03/29 20:33
upstream INFO: task hung in process_measurement integrity lsm 1 C done inconclusive 52 1576d 2608d 0/29 closed as invalid on 2022/02/08 10:56
upstream INFO: task hung in process_measurement (2) lsm integrity 1 C done 607 200d 804d 28/29 fixed on 2025/05/06 15:33
linux-4.19 INFO: task hung in process_measurement (3) 1 5 990d 995d 0/1 upstream: reported on 2023/03/02 09:48
linux-4.14 INFO: task hung in process_measurement 1 3 2077d 2133d 0/1 auto-closed as invalid on 2020/07/13 00:59
linux-6.1 INFO: task hung in process_measurement 1 39 494d 503d 0/3 auto-obsoleted due to no activity on 2024/09/23 07:47
linux-5.15 INFO: task hung in process_measurement (2) 1 97 394d 503d 0/3 auto-obsoleted due to no activity on 2025/01/01 08:25
linux-4.19 INFO: task hung in process_measurement (2) 1 1 1851d 1851d 0/1 auto-closed as invalid on 2021/02/23 17:00

Sample crash report:
INFO: task syz.5.243:5742 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.243       state:D stack:27904 pid:5742  ppid:4442   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 rwsem_down_write_slowpath+0xbed/0x1090 kernel/locking/rwsem.c:1189
 inode_lock include/linux/fs.h:758 [inline]
 process_measurement+0x33c/0x1a10 security/integrity/ima/ima_main.c:242
 ima_file_check+0xc2/0x100 security/integrity/ima/ima_main.c:534
 do_open fs/namei.c:3636 [inline]
 path_openat+0x2679/0x2e70 fs/namei.c:3791
 do_filp_open+0x1c1/0x3c0 fs/namei.c:3818
 do_sys_openat2+0x142/0x490 fs/open.c:1318
 do_sys_open fs/open.c:1334 [inline]
 __do_sys_open fs/open.c:1342 [inline]
 __se_sys_open fs/open.c:1338 [inline]
 __x64_sys_open+0x11b/0x140 fs/open.c:1338
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd2e858f6c9
RSP: 002b:00007fd2e938c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fd2e87e6180 RCX: 00007fd2e858f6c9
RDX: 0000000000000102 RSI: 00000000000e0142 RDI: 0000200000000180
RBP: 00007fd2e8611f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd2e87e6218 R14: 00007fd2e87e6180 R15: 00007fff1a4296d8
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8cb2b630 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8cb2be50 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
 #0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
5 locks held by kworker/u4:2/41:
2 locks held by getty/4033:
 #0: ffff88802fcbf098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198
2 locks held by kworker/0:13/4529:
 #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
 #1: ffffc90003427d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
3 locks held by kworker/u4:8/4542:
 #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
 #1: ffffc90004557d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
 #2: ffffffff8dd416e8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263
4 locks held by syz.5.243/5739:
 #0: ffff888056c5e460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:402
 #1: ffff888072d68e08 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff888072d68e08 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: do_truncate+0x183/0x220 fs/open.c:63
 #2: ffff888072d68fa8 (mapping.invalidate_lock){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:803 [inline]
 #2: ffff888072d68fa8 (mapping.invalidate_lock){++++}-{3:3}, at: ext4_setattr+0xe6f/0x19f0 fs/ext4/inode.c:5568
 #3: ffff888072d68c90 (&ei->i_data_sem){++++}-{3:3}, at: ext4_truncate+0x987/0x1230 fs/ext4/inode.c:4290
1 lock held by syz.5.243/5742:
 #0: ffff888072d68e08 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #0: ffff888072d68e08 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: process_measurement+0x33c/0x1a10 security/integrity/ima/ima_main.c:242
2 locks held by syz.3.691/7496:
 #0: ffffffff8dd416e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
 #0: ffffffff8dd416e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3492
 #1: ffffffff8cb30978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
 #1: ffffffff8cb30978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x455/0x830 kernel/rcu/tree_exp.h:962

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3f4/0x470 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xeee/0xf30 kernel/hung_task.c:377
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 41 Comm: kworker/u4:2 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:kasan_check_range+0x1ab/0x290 mm/kasan/generic.c:-1
Code: 4d 89 d6 4d 8d 56 07 4d 85 f6 4d 0f 49 d6 49 83 e2 f8 4d 29 d6 74 12 41 80 39 00 0f 85 a0 00 00 00 49 ff c1 49 ff ce 75 ee 5b <41> 5e 41 5f c3 84 db 75 61 f7 c3 00 ff 00 00 75 5e f7 c3 00 00 ff
RSP: 0018:ffffc90000b27538 EFLAGS: 00000256
RAX: 0000000000000001 RBX: 0000000000000010 RCX: ffffffff8138703a
RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc90000b27698
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff52000164ed5
R10: fffff52000164ed5 R11: 1ffff92000164ed3 R12: 1ffff92000164eca
R13: dffffc0000000000 R14: 0000000000000002 R15: dffffc0000000001
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4f0ece7e9c CR3: 000000000c88e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 memset+0x1e/0x40 mm/kasan/shadow.c:44
 unwind_next_frame+0xb8a/0x20b0 arch/x86/kernel/unwind_orc.c:546
 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516
 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3700
 skb_free_head net/core/skbuff.c:762 [inline]
 skb_release_data+0x5db/0x7c0 net/core/skbuff.c:791
 skb_release_all net/core/skbuff.c:856 [inline]
 __kfree_skb net/core/skbuff.c:870 [inline]
 consume_skb+0xa2/0x100 net/core/skbuff.c:1035
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline]
 nsim_dev_trap_report_work+0x76b/0xaf0 drivers/net/netdevsim/dev.c:851
 process_one_work+0x898/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/13 09:58 linux-6.1.y f6e38ae624cf 07e030de .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in process_measurement
* Struck through repros no longer work on HEAD.