panic: ffs_valloc: dup alloc
Stopped at      db_enter+0x25:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*238673  91272      0           0  0x4000000    0K syz-executor
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff83435b99) at panic+0x1e5 sys/kern/subr_prf.c:198
ffs_inode_alloc(fffffd80607b9150,4181,fffffd80097fd3a8,ffff80003c3df7f8) at ffs_inode_alloc+0x94e
ufs_mkdir(ffff80003c3df860) at ufs_mkdir+0xfc sys/ufs/ufs/ufs_vnops.c:1112
VOP_MKDIR(fffffd806b8f4010,ffff80003c3df9c0,ffff80003c3df9f0,ffff80003c3df8f0) at VOP_MKDIR+0x101 sys/kern/vfs_vops.c:394
domkdirat(ffff80003c3f22c0,ffffff9c,200000000080,183) at domkdirat+0x179 sys/kern/vfs_syscalls.c:3143
syscall(ffff80003c3dfb70) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80003c3dfb70) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x379cde26120, count: 7
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