panic: fifo_badop called
Stopped at      db_enter+0xa:   popq    %rbp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*291601  43109      0         0x2          0    0  syz-executor0
db_enter() at db_enter+0xa
panic() at panic+0x147
fifo_badop(ffffffff8169c4b2) at fifo_badop+0x12
VOP_STRATEGY(ffffff007ec31400) at VOP_STRATEGY+0x6b
bwrite(ffff800021142080) at bwrite+0x195
VOP_BWRITE(ffffff0069549970) at VOP_BWRITE+0x47
ufs_mkdir(ffffffff81dfb6d8) at ufs_mkdir+0x5a9
VOP_MKDIR(ffff8000ffffc4b8,1ed,ffffff9c,ffff800021142038) at VOP_MKDIR+0x65
domkdirat(ffff800021142270,ffff8000ffffc4b8,ffff8000210a5fd8,880) at domkdirat+0x10f
syscall(0) at syscall+0x3e4
Xsyscall(6,88,7f7fffff5410,88,0,7f7fffff5450) at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7fffff5480, count: 4
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