INFO: task syz.6.2993:15849 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.2993 state:D stack:25608 pid:15849 tgid:15849 ppid:7834 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5264 [inline] __schedule+0x1848/0x4ec0 kernel/sched/core.c:6872 __schedule_loop kernel/sched/core.c:6954 [inline] schedule+0x165/0x360 kernel/sched/core.c:6969 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7026 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 ima_check_last_writer security/integrity/ima/ima_main.c:192 [inline] ima_file_free+0x16c/0x460 security/integrity/ima/ima_main.c:233 security_file_release+0x93/0x150 security/security.c:2398 __fput+0x3b3/0xa70 fs/file_table.c:462 task_work_run+0x1d4/0x260 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:44 [inline] exit_to_user_mode_loop+0xff/0x4f0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2e9/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9d2298f6c9 RSP: 002b:00007ffe07dcefa8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f9d22be7da0 RCX: 00007f9d2298f6c9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f9d22be7da0 R08: 00000000000000c4 R09: 0000000b07dcf29f R10: 00007f9d22be7cb0 R11: 0000000000000246 R12: 0000000000100655 R13: 00007f9d22be6090 R14: ffffffffffffffff R15: 00007ffe07dcf0c0 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3d860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3d860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df3d860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5585: #0: ffff888033d300a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036c32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 4 locks held by kworker/0:3/15234: #0: ffff8880b863a1d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:638 #1: ffffffff8df3d860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #1: ffffffff8df3d860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #1: ffffffff8df3d860 (rcu_read_lock){....}-{1:3}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2074 [inline] #1: ffffffff8df3d860 (rcu_read_lock){....}-{1:3}, at: bpf_trace_run4+0x19c/0x4a0 kernel/trace/bpf_trace.c:2118 #2: ffff8880b8625b98 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline] #2: ffff8880b8625b98 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085 #3: ffffffff99afd160 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0xbb/0x420 lib/debugobjects.c:818 1 lock held by syz.6.2993/15849: #0: ffff888073ff19f8 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: ima_check_last_writer security/integrity/ima/ima_main.c:192 [inline] #0: ffff888073ff19f8 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: ima_file_free+0x16c/0x460 security/integrity/ima/ima_main.c:233 1 lock held by syz.6.2993/15850: 2 locks held by syz.0.3510/17413: #0: ffff88805e1e3008 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1051 [inline] #0: ffff88805e1e3008 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline] #0: ffff88805e1e3008 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1459 #1: ffffffff8df43338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #1: ffffffff8df43338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:957 1 lock held by syz.0.3510/17425: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:336 [inline] watchdog+0xfa9/0xff0 kernel/hung_task.c:499 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 17425 Comm: syz.0.3510 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216 Code: 8b 3d 04 89 d9 0b 48 89 de 5b e9 53 55 5b 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0c 25 08 30 75 92 65 8b 15 08 23 b4 10 81 e2 00 01 ff 00 RSP: 0018:ffffc9000cf576a0 EFLAGS: 00000202 RAX: ffffffff89328b03 RBX: 0000000000000000 RCX: 435c8d3c97118200 RDX: ffff88802f675b80 RSI: ffffffff8bbf40c0 RDI: ffffffff8bbf4080 RBP: 0000000000000000 R08: ffffffff8f7dc877 R09: 1ffffffff1efb90e R10: dffffc0000000000 R11: fffffbfff1efb90f R12: 0000000000000001 R13: 0000000000000001 R14: ffffc9000cf57cf0 R15: ffff88807a4bdc80 FS: 00007ff49bde76c0(0000) GS:ffff888125fcd000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b33d22ff8 CR3: 000000007a6ea000 CR4: 00000000003526f0 Call Trace: trace_skb_copy_datagram_iovec include/trace/events/skb.h:76 [inline] skb_copy_datagram_iter+0x93/0x230 net/core/datagram.c:534 skb_copy_datagram_msg include/linux/skbuff.h:4217 [inline] __unix_dgram_recvmsg+0x640/0xd60 net/unix/af_unix.c:2623 sock_recvmsg_nosec+0x186/0x1c0 net/socket.c:1082 ____sys_recvmsg+0x3aa/0x460 net/socket.c:2852 ___sys_recvmsg+0x1b5/0x510 net/socket.c:2896 do_recvmmsg+0x307/0x770 net/socket.c:2991 __sys_recvmmsg net/socket.c:3065 [inline] __do_sys_recvmmsg net/socket.c:3088 [inline] __se_sys_recvmmsg net/socket.c:3081 [inline] __x64_sys_recvmmsg+0x190/0x240 net/socket.c:3081 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff49af8f6c9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff49bde7038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007ff49b1e6180 RCX: 00007ff49af8f6c9 RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003 RBP: 00007ff49b011f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff49b1e6218 R14: 00007ff49b1e6180 R15: 00007ffd96af1698