panic: vput: ref cnt
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
* 15192  54661      0           0  0x4000000    1K syz-executor.0
 162848  57045      0         0x2  0x4000000    0  syz-fuzzer
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic() at panic+0x15c sys/kern/subr_prf.c:207
vput(fffffd80721ebb40) at vput+0x14b sys/kern/vfs_subr.c:750
vn_close(fffffd80721ebb40,2,fffffd807f7c6780,ffff800020b6f410) at vn_close+0xfb sys/kern/vfs_vnops.c:291
sys_acct(ffff800020b6f410,ffff800022e19068,ffff800022e190d0) at sys_acct+0x15b sys/kern/kern_acct.c:134
syscall(ffff800022e19140) at syscall+0x552 mi_syscall sys/sys/syscall_mi.h:92 [inline]
syscall(ffff800022e19140) at syscall+0x552 sys/arch/amd64/amd64/trap.c:555
Xsyscall(6,0,fffffffffffffec0,0,1,1391b710e0) at Xsyscall+0x128
end of kernel
end trace frame: 0x1604429260, count: 8
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