INFO: task syz-executor.2:4744 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:27872 pid: 4744 ppid: 4520 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 rwsem_down_write_slowpath+0xc46/0x11f0 kernel/locking/rwsem.c:1165 filemap_invalidate_lock include/linux/fs.h:832 [inline] blkdev_fallocate+0x263/0x4d0 block/fops.c:603 vfs_fallocate+0x587/0x6f0 fs/open.c:308 ksys_fallocate fs/open.c:331 [inline] __do_sys_fallocate fs/open.c:339 [inline] __se_sys_fallocate fs/open.c:337 [inline] __x64_sys_fallocate+0xbd/0x100 fs/open.c:337 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f853e425e69 RSP: 002b:00007f853d7a60c8 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007f853e553f80 RCX: 00007f853e425e69 RDX: 0000000000000000 RSI: 0000000000000011 RDI: 0000000000000004 RBP: 00007f853e47247a R08: 0000000000000000 R09: 0000000000000000 R10: 7fffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f853e553f80 R15: 00007fff69d1a708 INFO: task syz-executor.0:4772 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:27872 pid: 4772 ppid: 4517 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 rwsem_down_write_slowpath+0xc46/0x11f0 kernel/locking/rwsem.c:1165 filemap_invalidate_lock include/linux/fs.h:832 [inline] blkdev_fallocate+0x263/0x4d0 block/fops.c:603 vfs_fallocate+0x587/0x6f0 fs/open.c:308 ksys_fallocate fs/open.c:331 [inline] __do_sys_fallocate fs/open.c:339 [inline] __se_sys_fallocate fs/open.c:337 [inline] __x64_sys_fallocate+0xbd/0x100 fs/open.c:337 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fa87782fe69 RSP: 002b:00007fa876bb00c8 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007fa87795df80 RCX: 00007fa87782fe69 RDX: 0000000000000000 RSI: 0000000000000011 RDI: 0000000000000004 RBP: 00007fa87787c47a R08: 0000000000000000 R09: 0000000000000000 R10: 7fffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fa87795df80 R15: 00007ffeeeca9518 INFO: task syz-executor.3:4776 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:27200 pid: 4776 ppid: 4528 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 rwsem_down_write_slowpath+0xc46/0x11f0 kernel/locking/rwsem.c:1165 filemap_invalidate_lock include/linux/fs.h:832 [inline] blkdev_fallocate+0x263/0x4d0 block/fops.c:603 vfs_fallocate+0x587/0x6f0 fs/open.c:308 ksys_fallocate fs/open.c:331 [inline] __do_sys_fallocate fs/open.c:339 [inline] __se_sys_fallocate fs/open.c:337 [inline] __x64_sys_fallocate+0xbd/0x100 fs/open.c:337 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f393318fe69 RSP: 002b:00007f39325100c8 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007f39332bdf80 RCX: 00007f393318fe69 RDX: 0000000000000000 RSI: 0000000000000011 RDI: 0000000000000004 RBP: 00007f39331dc47a R08: 0000000000000000 R09: 0000000000000000 R10: 7fffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f39332bdf80 R15: 00007fffe680b6a8 Showing all locks held in the system: 3 locks held by kworker/0:0/7: #0: ffff88802ad4a538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90000cc7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4110 1 lock held by khungtaskd/27: #0: ffffffff8c11c760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 3 locks held by kworker/1:2/1110: #0: ffff88802ad4a538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90004b27d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4110 4 locks held by kworker/u4:3/1197: 2 locks held by getty/3948: #0: ffff88802b392098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900026562e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 3 locks held by kworker/1:7/4686: #0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90002fbfd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff888053ca6240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x271/0x3240 drivers/net/netdevsim/fib.c:1480 1 lock held by syz-executor.4/4728: 1 lock held by syz-executor.2/4744: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.0/4772: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.3/4776: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.1/5032: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.4/5059: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.2/5076: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.0/5086: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.3/5088: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.1/5111: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.4/5148: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.2/5194: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.0/5200: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.3/5204: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.1/5231: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.4/5259: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.2/5292: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.0/5311: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.3/5316: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3} , at: filemap_invalidate_lock include/linux/fs.h:832 [inline] , at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.1/5344: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 1 lock held by syz-executor.4/5373: #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:832 [inline] #0: ffff88802040c438 (mapping.invalidate_lock#2){++++}-{3:3}, at: blkdev_fallocate+0x263/0x4d0 block/fops.c:603 6 locks held by syz-executor.2/5375: 2 locks held by syz-executor.0/5393: #0: ffffffff8d22cd10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x32e/0x5b0 net/core/net_namespace.c:499 #1: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: register_nexthop_notifier+0x7d/0x210 net/ipv4/nexthop.c:3614 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5375 Comm: syz-executor.2 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:vsnprintf+0xb09/0x1a00 lib/vsprintf.c:2844 Code: 00 e8 ab f5 79 fd 48 8b 44 24 20 42 80 3c 30 00 4c 8b 7c 24 30 74 08 4c 89 ff e8 b2 5d be fd 4d 8b 27 49 8d 44 24 08 49 89 07 <4c> 89 e0 48 c1 e8 03 42 80 3c 30 00 0f 84 cc 05 00 00 4c 89 e7 e8 RSP: 0018:ffffc9000422e490 EFLAGS: 00000206 RAX: 0000000000000000 RBX: ffff0a0000000509 RCX: ffff88802a6a0000 RDX: ffffc9000422e580 RSI: 0000000000000010 RDI: 0000000000000029 RBP: ffffffff8a0bd2e5 R08: ffff88802a6a0000 R09: 0000000000000012 R10: 0000000000000012 R11: 0000000000000000 R12: ffffc9000422e540 R13: ffffc9000422e761 R14: dffffc0000000000 R15: 0000000000000018 FS: 0000555564293480(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f25a9f9e000 CR3: 000000007c068000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: sprintf+0xd6/0x120 lib/vsprintf.c:3013 print_time kernel/printk/printk.c:1274 [inline] info_print_prefix+0x152/0x300 kernel/printk/printk.c:1300 record_print_text kernel/printk/printk.c:1349 [inline] console_unlock+0x7f5/0x1200 kernel/printk/printk.c:2725 vprintk_emit+0xc0/0x150 kernel/printk/printk.c:2274 _printk+0xcc/0x110 kernel/printk/printk.c:2299 batadv_check_known_mac_addr+0x272/0x3b0 net/batman-adv/hard-interface.c:522 batadv_hard_if_event+0x4a0/0x17e0 net/batman-adv/hard-interface.c:986 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391 call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] dev_set_mac_address+0x2c4/0x3d0 net/core/dev.c:9114 dev_set_mac_address_user+0x2d/0x50 net/core/dev.c:9128 do_setlink+0x80d/0x3980 net/core/rtnetlink.c:2736 __rtnl_newlink net/core/rtnetlink.c:3452 [inline] rtnl_newlink+0x1419/0x17d0 net/core/rtnetlink.c:3574 rtnetlink_rcv_msg+0x7ff/0xe90 net/core/rtnetlink.c:5684 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2507 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] __sys_sendto+0x423/0x580 net/socket.c:2073 __do_sys_sendto net/socket.c:2085 [inline] __se_sys_sendto net/socket.c:2081 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2081 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f38f523ab5c Code: 1a 51 02 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 60 51 02 00 48 8b RSP: 002b:00007ffed0d5eb60 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f38f5e8f620 RCX: 00007f38f523ab5c RDX: 000000000000002c RSI: 00007f38f5e8f670 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffed0d5ebb4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f38f5e8f670 R15: 0000000000000000