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BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:835 [inline]
BUG: KASAN: use-after-free in hlist_del include/linux/list.h:852 [inline]
BUG: KASAN: use-after-free in __cpuhp_state_remove_instance+0x58b/0x5b0 kernel/cpu.c:2002
Read of size 8 at addr ffff88802cf40950 by task syz-executor.2/11016

CPU: 1 PID: 11016 Comm: syz-executor.2 Not tainted 5.11.0-next-20210301-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0xfa/0x151 lib/dump_stack.c:120
 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:232
 __kasan_report mm/kasan/report.c:399 [inline]
 kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416
 __hlist_del include/linux/list.h:835 [inline]
 hlist_del include/linux/list.h:852 [inline]
 __cpuhp_state_remove_instance+0x58b/0x5b0 kernel/cpu.c:2002
 cpuhp_state_remove_instance_nocalls include/linux/cpuhotplug.h:407 [inline]
 io_wq_create+0x6ca/0xce0 fs/io-wq.c:1053
 io_init_wq_offload fs/io_uring.c:7765 [inline]
 io_uring_alloc_task_context+0x1bf/0x6a0 fs/io_uring.c:7784
 io_uring_add_task_file+0x261/0x350 fs/io_uring.c:8748
 io_uring_install_fd fs/io_uring.c:9337 [inline]
 io_uring_create fs/io_uring.c:9488 [inline]
 io_uring_setup+0x14c7/0x2be0 fs/io_uring.c:9527
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x465ef9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb6ec181188 EFLAGS: 00000246 ORIG_RAX: 00000000000001a9
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465ef9
RDX: 0000000000000000 RSI: 0000000020000040 RDI: 000000000000241f
RBP: 00000000004bcd1c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffdf78fe13f R14: 00007fb6ec181300 R15: 0000000000022000

Allocated by task 11016:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:427 [inline]
 ____kasan_kmalloc mm/kasan/common.c:506 [inline]
 ____kasan_kmalloc mm/kasan/common.c:465 [inline]
 __kasan_kmalloc+0x99/0xc0 mm/kasan/common.c:515
 kmalloc include/linux/slab.h:554 [inline]
 kzalloc include/linux/slab.h:684 [inline]
 io_wq_create+0xc0/0xce0 fs/io-wq.c:996
 io_init_wq_offload fs/io_uring.c:7765 [inline]
 io_uring_alloc_task_context+0x1bf/0x6a0 fs/io_uring.c:7784
 io_uring_add_task_file+0x261/0x350 fs/io_uring.c:8748
 io_uring_install_fd fs/io_uring.c:9337 [inline]
 io_uring_create fs/io_uring.c:9488 [inline]
 io_uring_setup+0x14c7/0x2be0 fs/io_uring.c:9527
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Freed by task 11016:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:357
 ____kasan_slab_free mm/kasan/common.c:360 [inline]
 ____kasan_slab_free mm/kasan/common.c:325 [inline]
 __kasan_slab_free+0xf5/0x130 mm/kasan/common.c:367
 kasan_slab_free include/linux/kasan.h:199 [inline]
 slab_free_hook mm/slub.c:1562 [inline]
 slab_free_freelist_hook+0x72/0x1b0 mm/slub.c:1600
 slab_free mm/slub.c:3161 [inline]
 kfree+0xe5/0x7b0 mm/slub.c:4213
 io_wq_put fs/io-wq.c:1093 [inline]
 io_wq_fork_manager.part.0+0x168/0x1b0 fs/io-wq.c:799
 io_wq_fork_manager fs/io-wq.c:787 [inline]
 io_wq_create+0x9e4/0xce0 fs/io-wq.c:1047
 io_init_wq_offload fs/io_uring.c:7765 [inline]
 io_uring_alloc_task_context+0x1bf/0x6a0 fs/io_uring.c:7784
 io_uring_add_task_file+0x261/0x350 fs/io_uring.c:8748
 io_uring_install_fd fs/io_uring.c:9337 [inline]
 io_uring_create fs/io_uring.c:9488 [inline]
 io_uring_setup+0x14c7/0x2be0 fs/io_uring.c:9527
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff88802cf40800
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 336 bytes inside of
 512-byte region [ffff88802cf40800, ffff88802cf40a00)
The buggy address belongs to the page:
page:0000000087aaccb6 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2cf40
head:0000000087aaccb6 order:2 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head)
raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010841c80
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88802cf40800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802cf40880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88802cf40900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff88802cf40980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802cf40a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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