==================================================================
BUG: KASAN: slab-use-after-free in l2tp_tunnel_del_work+0xe5/0x330 net/l2tp/l2tp_core.c:1334
Read of size 8 at addr ffff8880286988b8 by task kworker/u8:35/13553

CPU: 0 PID: 13553 Comm: kworker/u8:35 Not tainted 6.10.0-rc4-syzkaller-00869-g185d72112b95 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: l2tp l2tp_tunnel_del_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 l2tp_tunnel_del_work+0xe5/0x330 net/l2tp/l2tp_core.c:1334
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3393
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 18291:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slub.c:4122 [inline]
 __kmalloc_noprof+0x1f9/0x400 mm/slub.c:4135
 kmalloc_noprof include/linux/slab.h:664 [inline]
 kzalloc_noprof include/linux/slab.h:778 [inline]
 l2tp_session_create+0x3b/0xc20 net/l2tp/l2tp_core.c:1675
 pppol2tp_connect+0xca3/0x17a0 net/l2tp/l2tp_ppp.c:782
 __sys_connect_file net/socket.c:2049 [inline]
 __sys_connect+0x2df/0x310 net/socket.c:2066
 __do_sys_connect net/socket.c:2076 [inline]
 __se_sys_connect net/socket.c:2073 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:2073
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 17833:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240
 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2196 [inline]
 slab_free mm/slub.c:4437 [inline]
 kfree+0x149/0x360 mm/slub.c:4558
 __sk_destruct+0x58/0x5f0 net/core/sock.c:2191
 rcu_do_batch kernel/rcu/tree.c:2535 [inline]
 rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2809
 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554
 __do_softirq kernel/softirq.c:588 [inline]
 invoke_softirq kernel/softirq.c:428 [inline]
 __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702

Last potentially related work creation:
 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541
 __call_rcu_common kernel/rcu/tree.c:3072 [inline]
 call_rcu+0x167/0xa70 kernel/rcu/tree.c:3176
 pppol2tp_release+0x24b/0x350 net/l2tp/l2tp_ppp.c:457
 __sock_release net/socket.c:659 [inline]
 sock_close+0xbc/0x240 net/socket.c:1421
 __fput+0x406/0x8b0 fs/file_table.c:422
 task_work_run+0x24f/0x310 kernel/task_work.c:180
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888028698800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 184 bytes inside of
 freed 1024-byte region [ffff888028698800, ffff888028698c00)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x28698
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffefff(slab)
raw: 00fff00000000040 ffff888015041dc0 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000100010 00000001ffffefff 0000000000000000
head: 00fff00000000040 ffff888015041dc0 dead000000000100 dead000000000122
head: 0000000000000000 0000000000100010 00000001ffffefff 0000000000000000
head: 00fff00000000003 ffffea0000a1a601 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4781, tgid 4781 (dhcpcd-run-hook), ts 32305500583, free_ts 32276965734
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1468
 prep_new_page mm/page_alloc.c:1476 [inline]
 get_page_from_freelist+0x2e43/0x2f00 mm/page_alloc.c:3420
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4678
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page+0x5f/0x120 mm/slub.c:2265
 allocate_slab+0x5a/0x2f0 mm/slub.c:2428
 new_slab mm/slub.c:2481 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3667
 __slab_alloc+0x58/0xa0 mm/slub.c:3757
 __slab_alloc_node mm/slub.c:3810 [inline]
 slab_alloc_node mm/slub.c:3989 [inline]
 __do_kmalloc_node mm/slub.c:4121 [inline]
 __kmalloc_noprof+0x257/0x400 mm/slub.c:4135
 kmalloc_noprof include/linux/slab.h:664 [inline]
 load_elf_phdrs fs/binfmt_elf.c:526 [inline]
 load_elf_binary+0x2f4/0x2620 fs/binfmt_elf.c:855
 search_binary_handler fs/exec.c:1797 [inline]
 exec_binprm fs/exec.c:1839 [inline]
 bprm_execve+0xaf8/0x17c0 fs/exec.c:1891
 do_execveat_common+0x553/0x700 fs/exec.c:1998
 do_execve fs/exec.c:2072 [inline]
 __do_sys_execve fs/exec.c:2148 [inline]
 __se_sys_execve fs/exec.c:2143 [inline]
 __x64_sys_execve+0x92/0xb0 fs/exec.c:2143
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 4779 tgid 4779 stack trace:
 free_unre