code wiki / _hdl_build / nx_nxe_exec_probe.nx
nx_nxe_exec_probe.nx
buildroot/runtime/_hdl_build/nx_nxe_exec_probe.nx
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nx_nxe_exec_probe.nx -- PROBE (cardinal rule 2: verify the runtime primitive before building on it).
Question: can we (a) mmap RWX memory, (b) write raw x86_64 machine code into it, (c) cast the raw address to a
typed function pointer and CALL it -- i.e. genuinely EXECUTE loaded code on this machine? If yes, the native NXE
loader can verify-then-execute. Payload = int64 f(int64 x){ return x*x + 1; } in SysV ABI (arg rdi, ret rax):
48 89 f8 mov rax, rdi
48 0f af c7 imul rax, rdi
48 ff c0 inc rax
c3 ret
f(7) must be 50. expect_exit: 0
dependencies 1 imports · 0 importers
imports: nx_syscalls.nx
imported by: nobody (leaf or entry point)
call flow from main pre-order; caps 40 nodes / depth 6 declared; ↻ = already shown
structs
| none |
consts
| 11 | const K_MAGIC_4096: i64 = 4096 |
functions
| 13 | func g_puts(s: *u8) -> i64 { var n: i64=0; while s[n]!=(0 as u8){n=n+1} sys_write(1,s,n); return 0 } |
| 14 | func g_pn(v: i64) -> i64 { let b: *u8=sys_mmap(28); var x: i64=v; if x<0{b[0]=45;sys_write(1,b,1);x=0-x} if x==0{b[0]=48;sys_write(1,b,1);return 0} var d: i64=0; var y: i64=x; while y>0{d=d+1;y=y/10} var i: i64=d-1; y=x; while i>=0{b[i]=(48+(y%10)) as u8;y=y/10;i=i-1} sys_write(1,b,d); return 0 } |
| 17 | func mmap_rwx(size: i64) -> *u8 { let r: i64 = __syscall(SYS_MMAP, 0, size, 7, 0x22, -1, 0); return r as *u8 } called by 1: main |
| 19 | func main() -> i64 |