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BUG: KASAN: slab-use-after-free in pwq_release_workfn+0x339/0x380 kernel/workqueue.c:4124
Read of size 4 at addr ffff888027754dc0 by task pool_workqueue_/3

CPU: 1 PID: 3 Comm: pool_workqueue_ Not tainted 6.6.0-rc2-syzkaller-00649-g5a1b322cb0b7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0xc4/0x620 mm/kasan/report.c:475
 kasan_report+0xda/0x110 mm/kasan/report.c:588
 pwq_release_workfn+0x339/0x380 kernel/workqueue.c:4124
 kthread_worker_fn+0x2ff/0xac0 kernel/kthread.c:823
 kthread+0x33c/0x440 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
 </TASK>

Allocated by task 18590:
 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0xa2/0xb0 mm/kasan/common.c:383
 kmalloc include/linux/slab.h:599 [inline]
 kzalloc include/linux/slab.h:720 [inline]
 alloc_workqueue+0x16f/0x1490 kernel/workqueue.c:4684
 wg_newlink+0x353/0x8f0 drivers/net/wireguard/device.c:343
 rtnl_newlink_create net/core/rtnetlink.c:3521 [inline]
 __rtnl_newlink+0x1177/0x1940 net/core/rtnetlink.c:3741
 rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3754
 rtnetlink_rcv_msg+0x3c4/0xdf0 net/core/rtnetlink.c:6480
 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2545
 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline]
 netlink_unicast+0x536/0x810 net/netlink/af_netlink.c:1368
 netlink_sendmsg+0x93c/0xe40 net/netlink/af_netlink.c:1910
 sock_sendmsg_nosec net/socket.c:730 [inline]
 sock_sendmsg+0xd9/0x180 net/socket.c:753
 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2541
 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2595
 __sys_sendmsg+0x117/0x1e0 net/socket.c:2624
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 18590:
 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:522
 ____kasan_slab_free mm/kasan/common.c:236 [inline]
 ____kasan_slab_free+0x15b/0x1b0 mm/kasan/common.c:200
 kasan_slab_free include/linux/kasan.h:164 [inline]
 slab_free_hook mm/slub.c:1800 [inline]
 slab_free_freelist_hook+0x114/0x1e0 mm/slub.c:1826
 slab_free mm/slub.c:3809 [inline]
 __kmem_cache_free+0xb8/0x2f0 mm/slub.c:3822
 alloc_workqueue+0xe76/0x1490 kernel/workqueue.c:4746
 wg_newlink+0x353/0x8f0 drivers/net/wireguard/device.c:343
 rtnl_newlink_create net/core/rtnetlink.c:3521 [inline]
 __rtnl_newlink+0x1177/0x1940 net/core/rtnetlink.c:3741
 rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3754
 rtnetlink_rcv_msg+0x3c4/0xdf0 net/core/rtnetlink.c:6480
 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2545
 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline]
 netlink_unicast+0x536/0x810 net/netlink/af_netlink.c:1368
 netlink_sendmsg+0x93c/0xe40 net/netlink/af_netlink.c:1910
 sock_sendmsg_nosec net/socket.c:730 [inline]
 sock_sendmsg+0xd9/0x180 net/socket.c:753
 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2541
 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2595
 __sys_sendmsg+0x117/0x1e0 net/socket.c:2624
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Last potentially related work creation:
 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492
 insert_work+0x38/0x230 kernel/workqueue.c:1647
 __queue_work+0xb77/0x1050 kernel/workqueue.c:1803
 call_timer_fn+0x19e/0x580 kernel/time/timer.c:1700
 expire_timers kernel/time/timer.c:1746 [inline]
 __run_timers+0x585/0xb10 kernel/time/timer.c:2022
 run_timer_softirq+0x58/0xd0 kernel/time/timer.c:2035
 __do_softirq+0x218/0x965 kernel/softirq.c:553

The buggy address belongs to the object at ffff888027754c00
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 448 bytes inside of
 freed 512-byte region [ffff888027754c00, ffff888027754e00)

The buggy address belongs to the physical page:
page:ffffea00009dd500 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x27754
head:ffffea00009dd500 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
ksm flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888012c41c80 ffffea0000739900 dead000000000003
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x152820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 13205, tgid 13205 (syz-executor.0), ts 1709582541302, free_ts 1708688412970
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1536
 prep_new_page mm/page_alloc.c:1543 [inline]
 get_page_from_freelist+0xee0/0x2f20 mm/page_alloc.c:3170
 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4426
 __alloc_pages_node include/linux/gfp.h:237 [inline]
 alloc_slab_page mm/slub.c:1872 [inline]
 allocate_slab+0xa1/0x380 mm/slub.c:2017
 new_slab mm/slub.c:2070 [inline]
 ___slab_alloc+0x8c7/0x1580 mm/slub.c:3223
 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322
 __slab_alloc_node mm/slub.c:3375 [inline]
 slab_alloc_node mm/slub.c:3468 [inline]
 __kmem_cache_alloc_node+0x131/0x340 mm/slub.c:3517
 __do_kmalloc_node mm/slab_common.c:1022 [inline]
 __kmalloc_node+0x52/0x110 mm/slab_common.c:1030
 kmalloc_array_node include/linux/slab.h:697 [inline]
 kcalloc_node include/linux/slab.h:702 [inline]
 memcg_alloc_slab_cgroups+0xa9/0x170 mm/memcontrol.c:2895
 account_slab mm/slab.h:636 [inline]
 allocate_slab+0x2cb/0x380 mm/slub.c:2035
 new_slab mm/slub.c:2070 [inline]
 ___slab_alloc+0x8c7/0x1580 mm/slub.c:3223
 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322
 __slab_alloc_node mm/slub.c:3375 [inline]
 slab_alloc_node mm/slub.c:3468 [inline]
 slab_alloc mm/slub.c:3486 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3493 [inline]
 kmem_cache_alloc+0x38c/0x3b0 mm/slub.c:3502
 __sigqueue_alloc+0x244/0x6b0 kernel/signal.c:437
 __send_signal_locked+0x745/0x11c0 kernel/signal.c:1129
 force_sig_info_to_task+0x22e/0x630 kernel/signal.c:1364
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1136 [inline]
 free_unref_page_prepare+0x476/0xa40 mm/page_alloc.c:2312
 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2405
 ops_free_list.part.0+0x11c/0x3d0 net/core/net_namespace.c:184
 ops_free_list net/core/net_namespace.c:182 [inline]
 cleanup_net+0x5ac/0xb20 net/core/net_namespace.c:618
 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630
 process_scheduled_works kernel/workqueue.c:2703 [inline]
 worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784
 kthread+0x33c/0x440 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304

Memory state around the buggy address:
 ffff888027754c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888027754d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888027754d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff888027754e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888027754e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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