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BUG: KASAN: double-free or invalid-free in slab_free mm/slub.c:3142 [inline]
BUG: KASAN: double-free or invalid-free in kfree+0xdb/0x360 mm/slub.c:4124

CPU: 0 PID: 8486 Comm: syz-executor.0 Not tainted 5.11.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __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_invalid_free+0x51/0x80 mm/kasan/report.c:355
 ____kasan_slab_free+0xfd/0x110 mm/kasan/common.c:341
 kasan_slab_free include/linux/kasan.h:188 [inline]
 slab_free_hook mm/slub.c:1547 [inline]
 slab_free_freelist_hook+0x5d/0x150 mm/slub.c:1580
 slab_free mm/slub.c:3142 [inline]
 kfree+0xdb/0x360 mm/slub.c:4124
 bdev_free_inode+0x57/0x80 fs/block_dev.c:787
 i_callback+0x3f/0x70 fs/inode.c:222
 rcu_do_batch kernel/rcu/tree.c:2489 [inline]
 rcu_core+0x5eb/0xf00 kernel/rcu/tree.c:2723
 __do_softirq+0x2a5/0x9f7 kernel/softirq.c:343
 asm_call_irq_on_stack+0xf/0x20
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
 do_softirq_own_stack+0xaa/0xd0 arch/x86/kernel/irq_64.c:77
 invoke_softirq kernel/softirq.c:226 [inline]
 __irq_exit_rcu kernel/softirq.c:420 [inline]
 irq_exit_rcu+0x134/0x200 kernel/softirq.c:432
 sysvec_apic_timer_interrupt+0x4d/0x100 arch/x86/kernel/apic/apic.c:1096
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:628
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:199
Code: 0f 1f 44 00 00 55 48 8b 74 24 08 48 89 fd 48 83 c7 18 e8 de 7c 6a f8 48 89 ef e8 66 31 6b f8 e8 31 3c 8a f8 fb bf 01 00 00 00 <e8> 56 41 5f f8 65 8b 05 7f e6 13 77 85 c0 74 02 5d c3 e8 bb 3b 12
RSP: 0018:ffffc900016dfae8 EFLAGS: 00000202
RAX: 000000000088a3e3 RBX: 0000000000000c9a RCX: ffffffff81580a37
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000001
RBP: ffffffff8b00a140 R08: 0000000000000001 R09: ffffffff8ebda7af
R10: fffffbfff1d7b4f5 R11: 0000000000000000 R12: dffffc0000000000
R13: 00000000000324a0 R14: ffff88801c009720 R15: ffff88801c009640
 spin_unlock_irq include/linux/spinlock.h:404 [inline]
 alloc_pid+0x412/0xd70 kernel/pid.c:236
 copy_process+0x2ce0/0x6fd0 kernel/fork.c:2115
 kernel_clone+0xe7/0xab0 kernel/fork.c:2464
 __do_sys_clone+0xc8/0x110 kernel/fork.c:2581
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45c7ea
Code: f7 d8 64 89 04 25 d4 02 00 00 64 4c 8b 0c 25 10 00 00 00 31 d2 4d 8d 91 d0 02 00 00 31 f6 bf 11 00 20 01 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 f5 00 00 00 85 c0 41 89 c5 0f 85 fc 00 00
RSP: 002b:00007ffe97cec4d0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffe97cec4d0 RCX: 000000000045c7ea
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffe97cec510 R08: 0000000000000001 R09: 0000000001fbc940
R10: 0000000001fbcc10 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000

Allocated by task 21986:
 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
 kmalloc include/linux/slab.h:552 [inline]
 kernfs_get_open_node fs/kernfs/file.c:571 [inline]
 kernfs_fop_open+0x957/0xd40 fs/kernfs/file.c:717
 do_dentry_open+0x4b9/0x11b0 fs/open.c:817
 do_open fs/namei.c:3254 [inline]
 path_openat+0x1b9a/0x2730 fs/namei.c:3371
 do_filp_open+0x17e/0x3c0 fs/namei.c:3398
 do_sys_openat2+0x16d/0x420 fs/open.c:1172
 do_sys_open fs/open.c:1188 [inline]
 __do_sys_open fs/open.c:1196 [inline]
 __se_sys_open fs/open.c:1192 [inline]
 __x64_sys_open+0x119/0x1c0 fs/open.c:1192
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 21986:
 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:188 [inline]
 slab_free_hook mm/slub.c:1547 [inline]
 slab_free_freelist_hook+0x5d/0x150 mm/slub.c:1580
 slab_free mm/slub.c:3142 [inline]
 kfree+0xdb/0x360 mm/slub.c:4124
 kernfs_fop_release+0xe3/0x190 fs/kernfs/file.c:779
 __fput+0x283/0x920 fs/file_table.c:280
 task_work_run+0xdd/0x190 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x249/0x250 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff888020896200
 which belongs to the cache kmalloc-128 of size 128
The buggy address is located 0 bytes inside of
 128-byte region [ffff888020896200, ffff888020896280)
The buggy address belongs to the page:
page:000000005a545fec refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x20896
flags: 0xfff00000000200(slab)
raw: 00fff00000000200 ffffea00008e0040 0000000a0000000a ffff888010041640
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888020896100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888020896180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888020896200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff888020896280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888020896300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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