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WARNING: CPU: 3 PID: 8684 at fs/namespace.c:1186 mntput_no_expire+0xade/0xcc0 fs/namespace.c:1186
Modules linked in:
CPU: 3 PID: 8684 Comm: syz-executor.0 Not tainted 5.13.0-rc6-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
RIP: 0010:mntput_no_expire+0xade/0xcc0 fs/namespace.c:1186
Code: ff 48 c7 c2 e0 20 79 89 be c3 02 00 00 48 c7 c7 a0 20 79 89 c6 05 1d fb e6 0b 01 e8 c3 8d 07 07 e9 3f fd ff ff e8 32 f6 a6 ff <0f> 0b e9 fc fc ff ff e8 26 f6 a6 ff e8 81 eb 92 ff 31 ff 89 c5 89
RSP: 0018:ffffc900202cfcd0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 1ffff92004059fa0 RCX: 0000000000000000
RDX: ffff88801a641c40 RSI: ffffffff81cde5be RDI: 0000000000000003
RBP: ffff88806a3c3c80 R08: 0000000000000000 R09: ffffffff902278af
R10: ffffffff81cde2b8 R11: 0000000000000000 R12: 0000000000000008
R13: ffffc900202cfd20 R14: 00000000ffffffff R15: 0000000000000008
FS:  0000000000000000(0000) GS:ffff88802cd00000(0063) knlGS:000000000a4c7380
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000000a4d7f1c CR3: 000000006c771000 CR4: 0000000000150ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 path_umount+0x7d4/0x1260 fs/namespace.c:1760
 ksys_umount fs/namespace.c:1779 [inline]
 __do_sys_umount fs/namespace.c:1784 [inline]
 __se_sys_umount fs/namespace.c:1782 [inline]
 __ia32_sys_umount+0x159/0x180 fs/namespace.c:1782
 do_syscall_32_irqs_on arch/x86/entry/common.c:78 [inline]
 __do_fast_syscall_32+0x67/0xe0 arch/x86/entry/common.c:143
 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:168
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7f53549
Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000ffd33fec EFLAGS: 00000292 ORIG_RAX: 0000000000000034
RAX: ffffffffffffffda RBX: 00000000ffd34090 RCX: 0000000000000002
RDX: 000000000816c000 RSI: 0000000000000000 RDI: 00000000080ea118
RBP: 00000000ffd34090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000