==================================================================
BUG: KASAN: slab-use-after-free in irq_can_move_pcntxt kernel/irq/internals.h:328 [inline]
BUG: KASAN: slab-use-after-free in migrate_one_irq kernel/irq/cpuhotplug.c:57 [inline]
BUG: KASAN: slab-use-after-free in irq_migrate_all_off_this_cpu+0xaaf/0xc30 kernel/irq/cpuhotplug.c:181
Read of size 8 at addr ffff88806d56d9a8 by task migration/1/27

CPU: 1 UID: 0 PID: 27 Comm: migration/1 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Stopper: multi_cpu_stop+0x0/0x4b0 kernel/stop_machine.c:199 <- __stop_cpus.constprop.0+0xb1/0x140
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x13d/0x4b0 mm/kasan/report.c:482
 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
 irq_can_move_pcntxt kernel/irq/internals.h:328 [inline]
 migrate_one_irq kernel/irq/cpuhotplug.c:57 [inline]
 irq_migrate_all_off_this_cpu+0xaaf/0xc30 kernel/irq/cpuhotplug.c:181
 fixup_irqs+0x2b/0x280 arch/x86/kernel/irq.c:474
 cpu_disable_common arch/x86/kernel/smpboot.c:1371 [inline]
 native_cpu_disable+0x59/0x80 arch/x86/kernel/smpboot.c:1383
 __cpu_disable arch/x86/include/asm/smp.h:73 [inline]
 take_cpu_down+0xb6/0x190 kernel/cpu.c:1282
 multi_cpu_stop+0x16a/0x4b0 kernel/stop_machine.c:239
 cpu_stopper_thread+0x21e/0x450 kernel/stop_machine.c:510
 smpboot_thread_fn+0x3d3/0xab0 kernel/smpboot.c:160
 kthread+0x373/0x450 kernel/kthread.c:436
 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 11255:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5414 [inline]
 __kvmalloc_node_noprof+0x35b/0x9b0 mm/slub.c:7005
 _kvmalloc_array_node_noprof include/linux/slab.h:1374 [inline]
 io_alloc_cache_init+0x38/0x170 io_uring/alloc_cache.c:25
 io_ring_ctx_alloc io_uring/io_uring.c:260 [inline]
 io_uring_create io_uring/io_uring.c:2976 [inline]
 io_uring_setup.cold+0x46e/0x1c5e io_uring/io_uring.c:3111
 __do_sys_io_uring_setup io_uring/io_uring.c:3145 [inline]
 __se_sys_io_uring_setup io_uring/io_uring.c:3136 [inline]
 __ia32_sys_io_uring_setup+0xc2/0x170 io_uring/io_uring.c:3136
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline]
 __do_fast_syscall_32+0x13a/0x8b0 arch/x86/entry/syscall_32.c:291
 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:316
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Freed by task 37:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2748 [inline]
 slab_free mm/slub.c:6499 [inline]
 kfree+0x22b/0x6d0 mm/slub.c:6792
 io_alloc_cache_free+0x1ca/0x2c0 io_uring/alloc_cache.c:16
 io_free_alloc_caches+0x2f/0x70 io_uring/io_uring.c:219
 io_ring_ctx_free io_uring/io_uring.c:2165 [inline]
 io_ring_exit_work+0x7a0/0xd59 io_uring/io_uring.c:2410
 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3387
 process_scheduled_works kernel/workqueue.c:3470 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3551
 kthread+0x373/0x450 kernel/kthread.c:436
 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff88806d56d800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 424 bytes inside of
 freed 1024-byte region [ffff88806d56d800, ffff88806d56dc00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88806d56f800 pfn:0x6d568
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x4fff00000000240(workingset|head|node=1|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 04fff00000000240 ffff88801c042dc0 ffffea0001450410 ffffea000134d010
raw: ffff88806d56f800 000000000010000c 00000000f5000000 0000000000000000
head: 04fff00000000240 ffff88801c042dc0 ffffea0001450410 ffffea000134d010
head: ffff88806d56f800 000000000010000c 00000000f5000000 0000000000000000
head: 04fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5784, tgid 5784 (kworker/u32:2), ts 50499596230
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
 prep_new_page mm/page_alloc.c:1879 [inline]
 get_page_from_freelist+0x110d/0x35b0 mm/page_alloc.c:3943
 __alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436
 alloc_slab_page mm/slub.c:3347 [inline]
 allocate_slab mm/slub.c:3462 [inline]
 new_slab+0xa9/0x6e0 mm/slub.c:3513
 refill_objects+0xe3/0x410 mm/slub.c:7410
 refill_sheaf mm/slub.c:2885 [inline]
 __pcs_replace_empty_main+0x35e/0x650 mm/slub.c:4774
 alloc_from_pcs mm/slub.c:4850 [inline]
 slab_alloc_node mm/slub.c:4984 [inline]
 __do_kmalloc_node mm/slub.c:5413 [inline]
 __kmalloc_noprof+0x67c/0x840 mm/slub.c:5439
 _kmalloc_noprof include/linux/slab.h:995 [inline]
 _kzalloc_noprof include/linux/slab.h:1312 [inline]
 neigh_alloc net/core/neighbour.c:518 [inline]
 ___neigh_create+0x1532/0x2940 net/core/neighbour.c:652
 ip6_finish_output2+0x1052/0x1d50 net/ipv6/ip6_output.c:130
 __ip6_finish_output+0x357/0xdf0 net/ipv6/ip6_output.c:210
 ip6_finish_output net/ipv6/ip6_output.c:221 [inline]
 NF_HOOK_COND include/linux/netfilter.h:314 [inline]
 ip6_output+0x2aa/0xa60 net/ipv6/ip6_output.c:248
 dst_output include/net/dst.h:470 [inline]
 NF_HOOK include/linux/netfilter.h:325 [inline]
 ndisc_send_skb+0xa85/0x1bf0 net/ipv6/ndisc.c:513
 ndisc_send_ns+0xc6/0x140 net/ipv6/ndisc.c:672
 addrconf_dad_work+0xca1/0x1360 net/ipv6/addrconf.c:4318
 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3387
 process_scheduled_works kernel/workqueue.c:3470 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3551
page last free pid 5871 tgid 5871 ts 50454049360 stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1418 [inline]
 __free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4683 [inline]
 slab_alloc_node mm/slub.c:4996 [inline]
 kmem_cache_alloc_noprof+0x269/0x6a0 mm/slub.c:5010
 anon_vma_chain_alloc mm/rmap.c:142 [inline]
 __anon_vma_prepare+0xae/0x5e0 mm/rmap.c:194
 __vmf_anon_prepare+0x11f/0x250 mm/memory.c:3899
 vmf_anon_prepare mm/internal.h:572 [inline]
 do_cow_fault mm/memory.c:5958 [inline]
 do_fault+0x1b4/0x1830 mm/memory.c:6074
 do_pte_missing mm/memory.c:4638 [inline]
 handle_pte_fault mm/memory.c:6496 [inline]
 __handle_mm_fault+0x150b/0x2f60 mm/memory.c:6645
 handle_mm_fault+0x37b/0xa30 mm/memory.c:6814
 do_user_addr_fault+0x59c/0x12f0 arch/x86/mm/fault.c:1343
 handle_page_fault arch/x86/mm/fault.c:1483 [inline]
 exc_page_fault+0x6f/0xd0 arch/x86/mm/fault.c:1536
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595

Memory state around the buggy address:
 ffff88806d56d880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88806d56d900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88806d56d980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff88806d56da00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88806d56da80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================