==================================================================
BUG: KASAN: use-after-free in radix_tree_next_slot include/linux/radix-tree.h:422 [inline]
BUG: KASAN: use-after-free in idr_for_each+0x206/0x220 lib/idr.c:202
Read of size 8 at addr ffff88806d0a0b38 by task syz-executor.0/29396

CPU: 0 PID: 29396 Comm: syz-executor.0 Not tainted 5.11.0-rc7-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+0x107/0x163 lib/dump_stack.c:120
 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:230
 __kasan_report mm/kasan/report.c:396 [inline]
 kasan_report.cold+0x79/0xd5 mm/kasan/report.c:413
 radix_tree_next_slot include/linux/radix-tree.h:422 [inline]
 idr_for_each+0x206/0x220 lib/idr.c:202
 io_ring_ctx_wait_and_kill+0x1bd/0x600 fs/io_uring.c:8798
 io_uring_release+0x3e/0x50 fs/io_uring.c:8823
 __fput+0x283/0x920 fs/file_table.c:280
 task_work_run+0xdd/0x190 kernel/task_work.c:140
 exit_task_work include/linux/task_work.h:30 [inline]
 do_exit+0xc5c/0x2ae0 kernel/exit.c:825
 do_group_exit+0x125/0x310 kernel/exit.c:922
 get_signal+0x427/0x20f0 kernel/signal.c:2773
 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:811
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]
 syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x465b09
Code: Unable to access opcode bytes at RIP 0x465adf.
RSP: 002b:00007f33cc63f218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000056c010 RCX: 0000000000465b09
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056c010
RBP: 000000000056c008 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c014
R13: 0000000000a9fb1f R14: 00007f33cc63f300 R15: 0000000000022000

Allocated by task 29389:
 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:401 [inline]
 ____kasan_kmalloc.constprop.0+0x82/0xa0 mm/kasan/common.c:429
 kasan_slab_alloc include/linux/kasan.h:209 [inline]
 slab_post_alloc_hook mm/slab.h:512 [inline]
 slab_alloc_node mm/slub.c:2892 [inline]
 slab_alloc mm/slub.c:2900 [inline]
 kmem_cache_alloc+0x1c6/0x440 mm/slub.c:2905
 radix_tree_node_alloc.constprop.0+0x7c/0x350 lib/radix-tree.c:274
 idr_get_free+0x554/0xa60 lib/radix-tree.c:1504
 idr_alloc_u32+0x170/0x2d0 lib/idr.c:46
 idr_alloc_cyclic+0x102/0x230 lib/idr.c:125
 io_register_personality fs/io_uring.c:9870 [inline]
 __io_uring_register fs/io_uring.c:10099 [inline]
 __do_sys_io_uring_register+0x1639/0x4090 fs/io_uring.c:10149
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 12:
 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:356
 ____kasan_slab_free+0xe1/0x110 mm/kasan/common.c:362
 kasan_slab_free include/linux/kasan.h:192 [inline]
 slab_free_hook mm/slub.c:1547 [inline]
 slab_free_freelist_hook+0x5d/0x150 mm/slub.c:1580
 slab_free mm/slub.c:3143 [inline]
 kmem_cache_free+0x82/0x350 mm/slub.c:3159
 rcu_do_batch kernel/rcu/tree.c:2489 [inline]
 rcu_core+0x5eb/0xf00 kernel/rcu/tree.c:2723
 __do_softirq+0x29b/0x9f6 kernel/softirq.c:343

Last potentially related work creation:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_record_aux_stack+0xc5/0xf0 mm/kasan/generic.c:344
 __call_rcu kernel/rcu/tree.c:2965 [inline]
 call_rcu+0xbb/0x700 kernel/rcu/tree.c:3038
 radix_tree_node_free lib/radix-tree.c:308 [inline]
 delete_node+0x591/0x8c0 lib/radix-tree.c:571
 __radix_tree_delete+0x190/0x370 lib/radix-tree.c:1377
 radix_tree_delete_item+0xe7/0x230 lib/radix-tree.c:1428
 io_remove_personalities+0x1d/0x170 fs/io_uring.c:8743
 idr_for_each+0x113/0x220 lib/idr.c:208
 io_ring_ctx_wait_and_kill+0x1bd/0x600 fs/io_uring.c:8798
 io_uring_release+0x3e/0x50 fs/io_uring.c:8823
 __fput+0x283/0x920 fs/file_table.c:280
 task_work_run+0xdd/0x190 kernel/task_work.c:140
 exit_task_work include/linux/task_work.h:30 [inline]
 do_exit+0xc5c/0x2ae0 kernel/exit.c:825
 do_group_exit+0x125/0x310 kernel/exit.c:922
 get_signal+0x427/0x20f0 kernel/signal.c:2773
 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:811
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]
 syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Second to last potentially related work creation:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_record_aux_stack+0xc5/0xf0 mm/kasan/generic.c:344
 __call_rcu kernel/rcu/tree.c:2965 [inline]
 call_rcu+0xbb/0x700 kernel/rcu/tree.c:3038
 radix_tree_node_free lib/radix-tree.c:308 [inline]
 delete_node+0xef/0x8c0 lib/radix-tree.c:571
 __radix_tree_delete+0x190/0x370 lib/radix-tree.c:1377
 radix_tree_delete_item+0xe7/0x230 lib/radix-tree.c:1428
 free_pid+0x9b/0x260 kernel/pid.c:152
 __change_pid+0x1c1/0x2d0 kernel/pid.c:353
 __unhash_process kernel/exit.c:78 [inline]
 __exit_signal kernel/exit.c:148 [inline]
 release_task+0xd29/0x14d0 kernel/exit.c:199
 wait_task_zombie kernel/exit.c:1107 [inline]
 wait_consider_task+0x2fd2/0x3b70 kernel/exit.c:1334
 do_wait_thread kernel/exit.c:1397 [inline]
 do_wait+0x376/0xa00 kernel/exit.c:1468
 kernel_wait4+0x14c/0x260 kernel/exit.c:1630
 __do_sys_wait4+0x13f/0x150 kernel/exit.c:1658
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff88806d0a0b00
 which belongs to the cache radix_tree_node of size 576
The buggy address is located 56 bytes inside of
 576-byte region [ffff88806d0a0b00, ffff88806d0a0d40)
The buggy address belongs to the page:
page:000000005c02921e refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6d0a0
head:000000005c02921e order:1 compound_mapcount:0
flags: 0xfff00000010200(slab|head)
raw: 00fff00000010200 0000000000000000 0000000600000001 ffff888010c4db40
raw: 0000000000000000 00000000800b000b 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88806d0a0a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88806d0a0a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88806d0a0b00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff88806d0a0b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88806d0a0c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================