panic: malloc: allocation too large, type = 2, size = 536870936

Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
  83469  83200      0           0          0    1  syz-executor.1
* 12159  83200      0           0  0x4000000    0K syz-executor.1
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic() at panic+0x174 sys/kern/subr_prf.c:208
malloc(20000018,2,2) at malloc+0xa6f sys/kern/kern_malloc.c:339
wsmux_getmux(4000002) at wsmux_getmux+0x71 sys/dev/wscons/wsmux.c:152
wsmux_add_mux(4000002,ffff800000026d00) at wsmux_add_mux+0x2f sys/dev/wscons/wsmux.c:594
VOP_IOCTL(fffffd8065e89d20,80085761,ffff800020c3b670,6,fffffd807f7c6840,ffff800020b74978) at VOP_IOCTL+0x9a sys/kern/vfs_vops.c:290
vn_ioctl(fffffd8068f19260,80085761,ffff800020c3b670,ffff800020b74978) at vn_ioctl+0xc9 sys/kern/vfs_vnops.c:512
sys_ioctl(ffff800020b74978,ffff800020c3b7b8,ffff800020c3b7a0) at sys_ioctl+0x651
syscall(ffff800020c3b850) at syscall+0x5b8 mi_syscall sys/sys/syscall_mi.h:99 [inline]
syscall(ffff800020c3b850) at syscall+0x5b8 sys/arch/amd64/amd64/trap.c:574
Xsyscall(6,0,ffffffffffffff86,0,3,3cbb4e08010) at Xsyscall+0x128
end of kernel
end trace frame: 0x3ce49387f20, count: 5
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