==================================================================
BUG: KASAN: slab-use-after-free in pwq_release_workfn+0x339/0x380 kernel/workqueue.c:4124
Read of size 4 at addr ffff8880209695c0 by task pool_workqueue_/3

CPU: 1 PID: 3 Comm: pool_workqueue_ Not tainted 6.6.0-rc1-syzkaller-00196-g57d88e8a5974 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
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+0x2fc/0xa80 kernel/kthread.c:823
 kthread+0x33a/0x430 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 28548:
 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+0xa3/0xb0 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
 kvm_mmu_init_tdp_mmu+0x23/0x100 arch/x86/kvm/mmu/tdp_mmu.c:19
 kvm_mmu_init_vm+0x248/0x2e0 arch/x86/kvm/mmu/mmu.c:6180
 kvm_arch_init_vm+0x39/0x720 arch/x86/kvm/x86.c:12311
 kvm_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:1222 [inline]
 kvm_dev_ioctl_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:5089 [inline]
 kvm_dev_ioctl+0xa31/0x1c20 arch/x86/kvm/../../../virt/kvm/kvm_main.c:5131
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl fs/ioctl.c:857 [inline]
 __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
 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 28548:
 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522
 ____kasan_slab_free mm/kasan/common.c:236 [inline]
 ____kasan_slab_free+0x138/0x190 mm/kasan/common.c:200
 kasan_slab_free include/linux/kasan.h:164 [inline]
 __cache_free mm/slab.c:3370 [inline]
 __do_kmem_cache_free mm/slab.c:3557 [inline]
 __kmem_cache_free+0xcc/0x2d0 mm/slab.c:3564
 alloc_workqueue+0xe76/0x1490 kernel/workqueue.c:4746
 kvm_mmu_init_tdp_mmu+0x23/0x100 arch/x86/kvm/mmu/tdp_mmu.c:19
 kvm_mmu_init_vm+0x248/0x2e0 arch/x86/kvm/mmu/mmu.c:6180
 kvm_arch_init_vm+0x39/0x720 arch/x86/kvm/x86.c:12311
 kvm_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:1222 [inline]
 kvm_dev_ioctl_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:5089 [inline]
 kvm_dev_ioctl+0xa31/0x1c20 arch/x86/kvm/../../../virt/kvm/kvm_main.c:5131
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl fs/ioctl.c:857 [inline]
 __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
 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+0x78/0x80 mm/kasan/generic.c:492
 kvfree_call_rcu+0x70/0xbe0 kernel/rcu/tree.c:3372
 ma_put net/ipv6/mcast.c:869 [inline]
 ma_put+0x11a/0x170 net/ipv6/mcast.c:865
 __ipv6_dev_mc_dec+0x297/0x360 net/ipv6/mcast.c:982
 ipv6_mc_destroy_dev+0x2cb/0x680 net/ipv6/mcast.c:2798
 addrconf_ifdown.isra.0+0x1597/0x1c50 net/ipv6/addrconf.c:3935
 addrconf_notify+0x22d/0x1920 net/ipv6/addrconf.c:3715
 notifier_call_chain+0xb6/0x3b0 kernel/notifier.c:93
 call_netdevice_notifiers_info+0xb9/0x130 net/core/dev.c:1970
 call_netdevice_notifiers_extack net/core/dev.c:2008 [inline]
 call_netdevice_notifiers net/core/dev.c:2022 [inline]
 unregister_netdevice_many_notify+0x85f/0x1a20 net/core/dev.c:10938
 unregister_netdevice_many net/core/dev.c:10994 [inline]
 unregister_netdevice_queue+0x2e5/0x3c0 net/core/dev.c:10874
 unregister_netdevice include/linux/netdevice.h:3106 [inline]
 __tun_detach+0x116f/0x1470 drivers/net/tun.c:684
 tun_detach drivers/net/tun.c:700 [inline]
 tun_chr_close+0xc8/0x240 drivers/net/tun.c:3496
 __fput+0x3f7/0xa70 fs/file_table.c:384
 __fput_sync+0x47/0x50 fs/file_table.c:465
 __do_sys_close fs/open.c:1572 [inline]
 __se_sys_close fs/open.c:1557 [inline]
 __x64_sys_close+0x87/0xf0 fs/open.c:1557
 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

Second to last potentially related work creation:
 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
 __kasan_record_aux_stack+0x78/0x80 mm/kasan/generic.c:492
 __call_rcu_common.constprop.0+0x9a/0x790 kernel/rcu/tree.c:2653
 fib6_info_release include/net/ip6_fib.h:332 [inline]
 fib6_info_release include/net/ip6_fib.h:329 [inline]
 __ip6_del_rt net/ipv6/route.c:3870 [inline]
 ip6_del_rt+0x1c2/0x200 net/ipv6/route.c:3881
 __ipv6_ifa_notify+0x431/0x11d0 net/ipv6/addrconf.c:6232
 addrconf_ifdown.isra.0+0xeed/0x1c50 net/ipv6/addrconf.c:3916
 addrconf_notify+0x22d/0x1920 net/ipv6/addrconf.c:3715
 notifier_call_chain+0xb6/0x3b0 kernel/notifier.c:93
 call_netdevice_notifiers_info+0xb9/0x130 net/core/dev.c:1970
 call_netdevice_notifiers_extack net/core/dev.c:2008 [inline]
 call_netdevice_notifiers net/core/dev.c:2022 [inline]
 dev_close_many+0x305/0x640 net/core/dev.c:1563
 unregister_netdevice_many_notify+0x41b/0x1a20 net/core/dev.c:10911
 unregister_netdevice_many net/core/dev.c:10994 [inline]
 default_device_exit_batch+0x584/0x740 net/core/dev.c:11453
 ops_exit_list+0x125/0x170 net/core/net_namespace.c:175
 cleanup_net+0x505/0xb20 net/core/net_namespace.c:614
 process_one_work+0x887/0x15d0 kernel/workqueue.c:2630
 process_scheduled_works kernel/workqueue.c:2703 [inline]
 worker_thread+0x8bb/0x1290 kernel/workqueue.c:2784
 kthread+0x33a/0x430 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

The buggy address belongs to the object at ffff888020969400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 448 bytes inside of
 freed 512-byte region [ffff888020969400, ffff888020969600)

The buggy address belongs to the physical page:
page:ffffea0000825a40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x20969
flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0x4()
raw: 00fff00000000800 ffff888012c40600 ffffea000096ce10 ffffea0001868890
raw: 0000000000000000 ffff888020969000 0000000100000004 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_THISNODE), pid 5180, tgid 5180 (syz-executor.1), ts 141153975970, free_ts 141061503852
 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]
 kmem_getpages mm/slab.c:1356 [inline]
 cache_grow_begin+0x99/0x3a0 mm/slab.c:2550
 cache_alloc_refill+0x294/0x3a0 mm/slab.c:2923
 ____cache_alloc mm/slab.c:2999 [inline]
 ____cache_alloc mm/slab.c:2982 [inline]
 __do_cache_alloc mm/slab.c:3182 [inline]
 slab_alloc_node mm/slab.c:3230 [inline]
 __kmem_cache_alloc_node+0x3c9/0x470 mm/slab.c:3521
 __do_kmalloc_node mm/slab_common.c:1022 [inline]
 __kmalloc+0x4f/0x100 mm/slab_common.c:1036
 kmalloc include/linux/slab.h:603 [inline]
 kzalloc include/linux/slab.h:720 [inline]
 fib6_info_alloc+0x40/0x160 net/ipv6/ip6_fib.c:155
 ip6_route_info_create+0x337/0x1e70 net/ipv6/route.c:3749
 ip6_route_add+0x26/0x150 net/ipv6/route.c:3843
 addrconf_prefix_route+0x300/0x510 net/ipv6/addrconf.c:2434
 add_v4_addrs+0x6be/0x9d0 net/ipv6/addrconf.c:3206
 addrconf_gre_config net/ipv6/addrconf.c:3480 [inline]
 addrconf_init_auto_addrs+0x18a/0x810 net/ipv6/addrconf.c:3498
 addrconf_notify+0xe65/0x1920 net/ipv6/addrconf.c:3679
 notifier_call_chain+0xb6/0x3b0 kernel/notifier.c:93
 call_netdevice_notifiers_info+0xb9/0x130 net/core/dev.c:1970
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
 slab_destroy mm/slab.c:1608 [inline]
 slabs_destroy+0x85/0xc0 mm/slab.c:1628
 cache_flusharray mm/slab.c:3341 [inline]
 ___cache_free+0x2b7/0x420 mm/slab.c:3404
 qlink_free mm/kasan/quarantine.c:166 [inline]
 qlist_free_all+0x4c/0x1b0 mm/kasan/quarantine.c:185
 kasan_quarantine_reduce+0x18b/0x1d0 mm/kasan/quarantine.c:292
 __kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook mm/slab.h:762 [inline]
 slab_alloc_node mm/slab.c:3237 [inline]
 __kmem_cache_alloc_node+0x167/0x470 mm/slab.c:3521
 kmalloc_trace+0x25/0xe0 mm/slab_common.c:1114
 kmalloc include/linux/slab.h:599 [inline]
 netdevice_queue_work drivers/infiniband/core/roce_gid_mgmt.c:643 [inline]
 netdevice_event+0x367/0x9a0 drivers/infiniband/core/roce_gid_mgmt.c:802
 notifier_call_chain+0xb6/0x3b0 kernel/notifier.c:93
 call_netdevice_notifiers_info+0xb9/0x130 net/core/dev.c:1970
 call_netdevice_notifiers_extack net/core/dev.c:2008 [inline]
 call_netdevice_notifiers net/core/dev.c:2022 [inline]
 dev_set_mac_address+0x36f/0x4a0 net/core/dev.c:8860
 dev_set_mac_address_user+0x30/0x50 net/core/dev.c:8874
 do_setlink+0x6e9/0x3fa0 net/core/rtnetlink.c:2828
 __rtnl_newlink+0xc1d/0x1940 net/core/rtnetlink.c:3671

Memory state around the buggy address:
 ffff888020969480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888020969500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888020969580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff888020969600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888020969680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================