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BUG: KASAN: stack-out-of-bounds in deref_stack_regs arch/x86/kernel/unwind_orc.c:304 [inline]
BUG: KASAN: stack-out-of-bounds in unwind_next_frame+0x146f/0x17d0 arch/x86/kernel/unwind_orc.c:437
Read of size 8 at addr ffff8880595bfc38 by task syz-executor.0/11499

CPU: 0 PID: 11499 Comm: syz-executor.0 Not tainted 4.14.305-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:251
 kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:350
 kasan_report mm/kasan/report.c:408 [inline]
 __asan_report_load8_noabort+0x68/0x70 mm/kasan/report.c:429
 deref_stack_regs arch/x86/kernel/unwind_orc.c:304 [inline]
 unwind_next_frame+0x146f/0x17d0 arch/x86/kernel/unwind_orc.c:437
 __save_stack_trace+0x90/0x160 arch/x86/kernel/stacktrace.c:44
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3496 [inline]
 kmem_cache_free+0x7c/0x2b0 mm/slab.c:3758
 __rcu_reclaim kernel/rcu/rcu.h:195 [inline]
 rcu_do_batch kernel/rcu/tree.c:2699 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2962 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2929 [inline]
 rcu_process_callbacks+0x780/0x1180 kernel/rcu/tree.c:2946
 __do_softirq+0x24d/0x9ff kernel/softirq.c:288
 invoke_softirq kernel/softirq.c:368 [inline]
 irq_exit+0x193/0x240 kernel/softirq.c:409
 exiting_irq arch/x86/include/asm/apic.h:638 [inline]
 smp_apic_timer_interrupt+0x141/0x5e0 arch/x86/kernel/apic/apic.c:1106
 apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:796
 </IRQ>
RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:774 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/paravirt.h:796 [inline]
RIP: 0010:lock_acquire+0x97/0x3f0 kernel/locking/lockdep.c:3993
RSP: 0018:ffff8880595bfad8 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff10
RAX: 1ffffffff11e13d8 RBX: ffff88809dc305c0 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff88809dc30e44
RBP: ffffffff88fece60 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: ffff88809dc305c0 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001
 pcpu_alloc+0x8e8/0xf50 mm/percpu.c:1380
 retint_kernel+0x2d/0x2d
RIP: 0010:__mutex_lock+0x15/0x1310 kernel/locking/mutex.c:892
RSP: 14000c0:ffff8880595bfc68 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: 0000000000040000 RBX: 00000000014000c0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffffffff8789e880
RBP: 0000000000000007 R08: ffffffff8171b7a8 R09: 0000000000000000
R10: 0000000000000000 R11: ffff88809dc305c0 R12: ffff8880a95cb800
R13: 0000000000000001 R14: ffffffff88fece00 R15: ffffffff8171b7a8
 pcpu_alloc+0x8e8/0xf50 mm/percpu.c:1380
 alloc_vfsmnt+0x128/0x7f0 fs/namespace.c:220
 vfs_kern_mount.part.0+0x27/0x470 fs/namespace.c:1039
 vfs_kern_mount fs/namespace.c:1036 [inline]
 do_new_mount fs/namespace.c:2572 [inline]
 do_mount+0xe65/0x2a30 fs/namespace.c:2905
 SYSC_mount fs/namespace.c:3121 [inline]
 SyS_mount+0xa8/0x120 fs/namespace.c:3098
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x5e/0xd3
RIP: 0033:0x7fac2a0a20f9
RSP: 002b:00007fac28614168 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
sctp: [Deprecated]: syz-executor.1 (pid 11490) Use of int in maxseg socket option.
Use struct sctp_assoc_value instead
RAX: ffffffffffffffda RBX: 00007fac2a1c1f80 RCX: 00007fac2a0a20f9
RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000000000000
RBP: 00007fac2a0fdae9 R08: 0000000020000780 R09: 0000000000000000
R10: 0000000000008000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff493cf7cf R14: 00007fac28614300 R15: 0000000000022000

The buggy address belongs to the page:
page:ffffea0001656fc0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0xfff00000000000()
raw: 00fff00000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 0000000100000001 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880595bfb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880595bfb80: 00 00 00 f1 f1 f1 f1 00 00 00 f2 00 00 00 f2 f2
>ffff8880595bfc00: f2 00 00 00 00 00 f3 f3 f3 f3 f3 00 00 00 00 00
                                        ^
 ffff8880595bfc80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880595bfd00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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