panic: ffs_valloc: dup alloc
Stopped at      db_enter+0x25:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*442879  51482      0           0  0x4000000    1K syz-executor
 476024  32226      0           0          0    0  syz-executor
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:437
panic(ffffffff830e4c22) at panic+0x1e5 sys/kern/subr_prf.c:198
ffs_inode_alloc(fffffd8074de9120,8000,fffffd807f7d34e0,ffff8000349bfce0) at ffs_inode_alloc+0x96c sys/ufs/ffs/ffs_alloc.c:404
ufs_makeinode(8000,fffffd80729126c8,ffff8000349c0018,ffff8000349c0048) at ufs_makeinode+0xcb sys/ufs/ufs/ufs_vnops.c:1728
ufs_create(ffff8000349bfd90) at ufs_create+0x4e sys/ufs/ufs/ufs_vnops.c:147
VOP_CREATE(fffffd80729126c8,ffff8000349c0018,ffff8000349c0048,ffff8000349bfe18) at VOP_CREATE+0xff sys/kern/vfs_vops.c:103
vn_open(ffff8000349bffe8,c6515b79,0) at vn_open+0x491 sys/kern/vfs_vnops.c:116
doopenat(ffff8000ffff3460,ffffff9c,20000180,c6515f78,0,ffff8000349c0190) at doopenat+0x31d sys/kern/vfs_syscalls.c:1123
syscall(ffff8000349c0240) at syscall+0xaf8 mi_syscall sys/sys/syscall_mi.h:179 [inline]
syscall(ffff8000349c0240) at syscall+0xaf8 sys/arch/amd64/amd64/trap.c:577
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xd977572f210, count: 5
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