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BUG: KASAN: stack-out-of-bounds in get_reg arch/x86/kernel/unwind_orc.c:411 [inline]
BUG: KASAN: stack-out-of-bounds in unwind_next_frame+0x17b3/0x1f90 arch/x86/kernel/unwind_orc.c:585
Read of size 8 at addr ffffc900186cf658 by task syz-executor.3/32413

CPU: 1 PID: 32413 Comm: syz-executor.3 Not tainted 5.9.0-rc7-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:77 [inline]
 dump_stack+0x198/0x1fd lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0x5/0x497 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 get_reg arch/x86/kernel/unwind_orc.c:411 [inline]
 unwind_next_frame+0x17b3/0x1f90 arch/x86/kernel/unwind_orc.c:585
 arch_stack_walk+0x81/0xf0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:123
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56
 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355
 __kasan_slab_free+0xd8/0x120 mm/kasan/common.c:422
 __cache_free mm/slab.c:3422 [inline]
 kmem_cache_free.part.0+0x74/0x1e0 mm/slab.c:3697
 rcu_do_batch kernel/rcu/tree.c:2430 [inline]
 rcu_core+0x5ca/0x1130 kernel/rcu/tree.c:2658
 __do_softirq+0x1f8/0xb23 kernel/softirq.c:298
 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+0x9b/0xd0 arch/x86/kernel/irq_64.c:77
 invoke_softirq kernel/softirq.c:393 [inline]
 __irq_exit_rcu kernel/softirq.c:423 [inline]
 irq_exit_rcu+0x235/0x280 kernel/softirq.c:435
 sysvec_apic_timer_interrupt+0x51/0xf0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:765 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/paravirt.h:787 [inline]
RIP: 0010:lock_acquire+0x143/0xaf0 kernel/locking/lockdep.c:5025
Code: 6b fc 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 2d 08 00 00 48 83 3d f4 61 a0 08 00 0f 84 9c 06 00 00 9c <58> 0f 1f 44 00 00 48 ba 00 00 00 00 00 fc ff df 49 89 c7 48 c7 c0
RSP: 0018:ffffc900186cf448 EFLAGS: 00000286
RAX: 1ffffffff13f8d7c RBX: 0000000000000001 RCX: ffffffff815c096e
RDX: dffffc0000000000 RSI: ffffffff8a067e80 RDI: 0000000000000000
RBP: ffffffff8a168ba0 R08: 0000000000000000 R09: ffffffff8b59654f
R10: fffffbfff16b2ca9 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: ffff888049fe2580
 kmalloc include/linux/slab.h:559 [inline]
 kzalloc include/linux/slab.h:666 [inline]
 __register_sysctl_table+0x112/0x1090 fs/proc/proc_sysctl.c:1314
 lockdep_hardirqs_on+0x53/0x100 kernel/locking/lockdep.c:3759
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
RIP: 4fa81e00:0x1ffff920030d9edf
Code: Bad RIP value.
RSP: 3903a180:ffff88805c9cc000 EFLAGS: ffff88808e27e980 ORIG_RAX: a593f43251f5dc00
RAX: 0000000000040000 RBX: ffffffff89b38688 RCX: ffffc9000ee1b000
RDX: ffff88804fa81e00 RSI: ffffc900186cf718 RDI: ffff88803903a2f0
RBP: 0000000041b58ab3 R08: 0000000000000004 R09: ffffc900186cf725
R10: 0000000000000000 R11: ffffffff81ead300 R12: ffff88808e27e980
R13: ffff88805c9cc000 R14: 1ffff920030d9ecb R15: ffffc900186cf718


addr ffffc900186cf658 is located in stack of task syz-executor.3/32413 at offset 0 in frame:
 __register_sysctl_table+0x0/0x1090 include/linux/list.h:831

this frame has 1 object:
 [32, 40) 'head'

Memory state around the buggy address:
 ffffc900186cf500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc900186cf580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc900186cf600: 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00
                                                    ^
 ffffc900186cf680: f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 f1
 ffffc900186cf700: f1 f1 f1 00 00 00 07 f3 f3 f3 f3 00 00 00 00 00
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