INFO: task syz.1.27:6627 blocked for more than 143 seconds.
Not tainted syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.27 state:D stack:26760 pid:6627 tgid:6627 ppid:6298 task_flags:0x40004c flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14cf/0x50c0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
rwsem_down_write_slowpath+0x91a/0x10b0 kernel/locking/rwsem.c:1185
__down_write_common kernel/locking/rwsem.c:1317 [inline]
__down_write kernel/locking/rwsem.c:1326 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591
mmap_write_lock include/linux/mmap_lock.h:312 [inline]
exit_mmap+0x27e/0xb00 mm/mmap.c:1288
__mmput+0x118/0x420 kernel/fork.c:1130
exit_mm+0x1da/0x2c0 kernel/exit.c:583
do_exit+0x658/0x2300 kernel/exit.c:961
do_group_exit+0x21c/0x2d0 kernel/exit.c:1114
__do_sys_exit_group kernel/exit.c:1125 [inline]
__se_sys_exit_group kernel/exit.c:1123 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1123
x64_sys_call+0x2210/0x2210 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x8a/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f828d58f749
RSP: 002b:00007ffd486d6408 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f828d58f749
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffd486d646c R08: 00000005486d64ff R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000006
R13: 00000000000927c0 R14: 000000000001febb R15: 00007ffd486d64c0
INFO: task syz.1.27:6627 is blocked on an rw-semaphore, but the owner is not found.
INFO: task dhcpcd-run-hook:6630 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:dhcpcd-run-hook state:D stack:26360 pid:6630 tgid:6630 ppid:6608 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14cf/0x50c0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
rwsem_down_write_slowpath+0x91a/0x10b0 kernel/locking/rwsem.c:1185
__down_write_common kernel/locking/rwsem.c:1317 [inline]
__down_write kernel/locking/rwsem.c:1326 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591
mmap_write_lock include/linux/mmap_lock.h:312 [inline]
exit_mmap+0x27e/0xb00 mm/mmap.c:1288
__mmput+0x118/0x420 kernel/fork.c:1130
exec_mmap+0x40c/0x4d0 fs/exec.c:901
begin_new_exec+0x1353/0x23f0 fs/exec.c:1156
load_elf_binary+0x998/0x2730 fs/binfmt_elf.c:1010
search_binary_handler fs/exec.c:1669 [inline]
exec_binprm fs/exec.c:1701 [inline]
bprm_execve+0x92e/0x1400 fs/exec.c:1753
do_execveat_common+0x510/0x6a0 fs/exec.c:1859
do_execve fs/exec.c:1933 [inline]
__do_sys_execve fs/exec.c:2009 [inline]
__se_sys_execve fs/exec.c:2004 [inline]
__x64_sys_execve+0x94/0xb0 fs/exec.c:2004
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x8a/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f4e899f2107
RSP: 002b:00007fff2a565ab8 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 00005655361dc1a8 RCX: 00007f4e899f2107
RDX: 00005655361d7e28 RSI: 00005655361dc1a8 RDI: 00005655361d7eb0
RBP: 00005655361d7eb0 R08: 00007fff2a568eb2 R09: 0000000000000210
R10: 0000000000000002 R11: 0000000000000246 R12: 00005655361d7e28
R13: 00007f4e89bb7e8b R14: 00005655361d7e28 R15: 0000000000000000
INFO: task dhcpcd-run-hook:6630 is blocked on an rw-semaphore, but the owner is not found.
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
1 lock held by klogd/5091:
2 locks held by udevd/5102:
#0: ffffffff8dbf53f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1485 [inline]
#0: ffffffff8dbf53f0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x131/0x4b0 kernel/fork.c:1538
#1: ffff88804c9bd740 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:330 [inline]
#1: ffff88804c9bd740 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x125/0x1ca0 mm/mmap.c:1727
2 locks held by getty/5488:
#0: ffff88802e2ae0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5ce/0x1aa0 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/6143:
#0: ffff88805a3bef40 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:330 [inline]
#0: ffff88805a3bef40 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x211/0x4d0 mm/util.c:579
1 lock held by syz-executor/6296:
#0: ffff888023123f40 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff888023123f40 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
1 lock held by syz-executor/6298:
#0: ffff88804c611b40 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff88804c611b40 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
1 lock held by syz-executor/6305:
#0: ffff88804c75bf40 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff88804c75bf40 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
1 lock held by syz-executor/6308:
#0: ffff88804c613340 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff88804c613340 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
1 lock held by syz-executor/6313:
#0: ffff88804c492740 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff88804c492740 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
1 lock held by syz.1.27/6627:
#0: ffff88807ca0cb40 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff88807ca0cb40 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
3 locks held by dhcpcd-run-hook/6630:
#0: ffff88802d6dc720 (&sig->cred_guard_mutex){+.+.}-{4:4}, at: prepare_bprm_creds fs/exec.c:1360 [inline]
#0: ffff88802d6dc720 (&sig->cred_guard_mutex){+.+.}-{4:4}, at: bprm_execve+0xb9/0x1400 fs/exec.c:1733
#1: ffff88802d6dc7b8 (&sig->exec_update_lock){+.+.}-{4:4}, at: exec_mmap+0xeb/0x4d0 fs/exec.c:856
#2: ffff88802e082740 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#2: ffff88802e082740 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
1 lock held by syz-executor/7770:
#0: ffff888021fd8f40 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff888021fd8f40 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
1 lock held by syz-executor/7780:
#0: ffff888021fde340 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff888021fde340 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
1 lock held by udevd/7783:
#0: ffff888021fdcb40 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:330 [inline]
#0: ffff888021fdcb40 (&mm->mmap_lock){++++}-{4:4}, at: __vm_munmap+0x136/0x380 mm/vma.c:3153
1 lock held by syz-executor/7788:
#0: ffff88804c0ae340 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff88804c0ae340 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
1 lock held by syz.5.726/8127:
#0: ffff88807883a740 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff88807883a740 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
1 lock held by syz.4.732/8139:
#0: ffff888078838340 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff888078838340 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
1 lock held by syz.6.735/8147:
#0: ffff888021fdbf40 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff888021fdbf40 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
1 lock held by syz.8.604/8148:
#0: ffff88807883cb40 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff88807883cb40 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
1 lock held by syz-executor/8156:
#0: ffff8880315c8f40 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff8880315c8f40 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
2 locks held by syz-executor/8161:
#0: ffffffff8dbf53f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1485 [inline]
#0: ffffffff8dbf53f0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x131/0x4b0 kernel/fork.c:1538
#1: ffff8880315cb340 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:330 [inline]
#1: ffff8880315cb340 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x125/0x1ca0 mm/mmap.c:1727
2 locks held by syz-executor/8168:
#0: ffffffff8dbf53f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1485 [inline]
#0: ffffffff8dbf53f0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x131/0x4b0 kernel/fork.c:1538
#1: ffff8880315cd740 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:330 [inline]
#1: ffff8880315cd740 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x125/0x1ca0 mm/mmap.c:1727
5 locks held by kworker/u8:24/8356:
#0: ffff8880b893a798 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:639
#1: ffff8880b8924448 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:220 [inline]
#1: ffff8880b8924448 (psi_seq){-.-.}-{0:0}, at: __schedule+0x24fb/0x50c0 kernel/sched/core.c:6857
#2: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#2: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#2: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: batadv_mcast_mla_rtr_flags_meshif_get net/batman-adv/multicast.c:170 [inline]
#2: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: batadv_mcast_mla_rtr_flags_get net/batman-adv/multicast.c:231 [inline]
#2: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: batadv_mcast_mla_flags_get net/batman-adv/multicast.c:285 [inline]
#2: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: __batadv_mcast_mla_update net/batman-adv/multicast.c:907 [inline]
#2: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: batadv_mcast_mla_update+0x126/0x3510 net/batman-adv/multicast.c:946
#3: ffffffff994aad90 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x87/0x540 lib/debugobjects.c:818
#4: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#4: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#4: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
#4: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xa5/0x2390 arch/x86/kernel/unwind_orc.c:479
1 lock held by syz.9.801/8388:
#0: ffff88807bcd3f40 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff88807bcd3f40 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
1 lock held by syz.0.802/8390:
#0: ffff888078bc4b40 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff888078bc4b40 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
1 lock held by syz.1.737/8392:
#0: ffff88807bcd6f40 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline]
#0: ffff88807bcd6f40 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27e/0xb00 mm/mmap.c:1288
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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/0x2e0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0x16db/0x1720 kernel/hung_task.c:495
kthread+0x711/0x890 kernel/kthread.c:463
ret_from_fork+0x595/0xb20 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5091 Comm: klogd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:1089 [inline]
RIP: 0010:debug_check_no_obj_freed+0x1d4/0x550 lib/debugobjects.c:1129
Code: 89 ef e8 1f 18 00 00 48 ba 00 00 00 00 00 fc ff df ff c3 48 8b 04 24 48 89 c5 48 85 c0 0f 84 44 03 00 00 49 89 ee 49 c1 ee 03 <41> 80 3c 16 00 74 12 48 89 ef e8 bd 37 96 fd 48 ba 00 00 00 00 00
RSP: 0018:ffffc9000ebcf7b0 EFLAGS: 00000806
RAX: ffff888078777268 RBX: 0000000000000008 RCX: dffffc0000000001
RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffc9000ebcf6a0
RBP: ffff888078777268 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52001d79ed4 R12: ffff88808aac0000
R13: ffff88808aab8000 R14: 1ffff1100f0eee4d R15: ffff88801f71b0f8
FS: 00007ff0b0b51c80(0000) GS:ffff888126760000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c008151010 CR3: 000000004c8ec000 CR4: 00000000003526f0
Call Trace:
free_pages_prepare mm/page_alloc.c:1401 [inline]
__free_frozen_pages+0x4d8/0xd00 mm/page_alloc.c:2901
discard_slab mm/slub.c:3346 [inline]
__put_partials+0x144/0x160 mm/slub.c:3886
put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3961
__slab_free+0x288/0x2a0 mm/slub.c:5947
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x60 mm/kasan/common.c:352
kasan_slab_alloc include/linux/kasan.h:252 [inline]
slab_post_alloc_hook mm/slub.c:4948 [inline]
slab_alloc_node mm/slub.c:5258 [inline]
__kmalloc_cache_noprof+0x36a/0x6c0 mm/slub.c:5766
kmalloc_noprof include/linux/slab.h:957 [inline]
syslog_print+0xd9/0x840 kernel/printk/printk.c:1583
do_syslog+0x544/0x760 kernel/printk/printk.c:1761
__do_sys_syslog kernel/printk/printk.c:1853 [inline]
__se_sys_syslog kernel/printk/printk.c:1851 [inline]
__x64_sys_syslog+0x7c/0x90 kernel/printk/printk.c:1851
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x8a/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7ff0b0d1ba37
Code: 73 01 c3 48 8b 0d c1 f3 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 67 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 91 f3 0c 00 f7 d8 64 89 01 48
RSP: 002b:00007ffe6e1a8948 EFLAGS: 00000206 ORIG_RAX: 0000000000000067
RAX: ffffffffffffffda RBX: 00007ff0b0ebb490 RCX: 00007ff0b0d1ba37
RDX: 00000000000003ff RSI: 00007ff0b0ebb490 RDI: 0000000000000002
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000206 R12: 00007ff0b0ebb490
R13: 00007ff0b0e98dfe R14: 00007ff0b0ebb780 R15: 00007ff0b0ebb780