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BUG: KASAN: unknown-crash in stack_not_used include/linux/sched/task_stack.h:101 [inline]
BUG: KASAN: unknown-crash in check_stack_usage kernel/exit.c:692 [inline]
BUG: KASAN: unknown-crash in do_exit+0x1646/0x1f20 kernel/exit.c:849
Read of size 8 at addr ffffc9001576c000 by task syz-executor.3/11194

CPU: 0 PID: 11194 Comm: syz-executor.3 Not tainted 5.9.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d6/0x29e lib/dump_stack.c:118
 print_address_description+0x66/0x620 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report+0x132/0x1d0 mm/kasan/report.c:530
 stack_not_used include/linux/sched/task_stack.h:101 [inline]
 check_stack_usage kernel/exit.c:692 [inline]
 do_exit+0x1646/0x1f20 kernel/exit.c:849
 do_group_exit+0x161/0x2d0 kernel/exit.c:903
 __do_sys_exit_group+0x13/0x20 kernel/exit.c:914
 __se_sys_exit_group+0x10/0x10 kernel/exit.c:912
 __x64_sys_exit_group+0x37/0x40 kernel/exit.c:912
 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45d5f9
Code: Bad RIP value.
RSP: 002b:00007fff62ab14a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 000000000000001e RCX: 000000000045d5f9
RDX: 0000000000416f41 RSI: fffffffffffffff7 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 00007fff62ab1500
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fff62ab1500 R14: 0000000000000000 R15: 00007fff62ab1510


Memory state around the buggy address:
 ffffc9001576bf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9001576bf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc9001576c000: 70 77 77 07 00 00 00 00 00 00 00 00 00 00 00 00
                   ^
 ffffc9001576c080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9001576c100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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