Split live rootfs into smaller squashfs layers

audit/internal/platform/install.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"os"
 	"os/exec"
+	"path/filepath"
 	"strconv"
 	"strings"
 )
@@ -18,7 +19,7 @@ type InstallDisk struct {
 	MountedParts []string // partition mount points currently active
 }
 
-const squashfsPath = "/run/live/medium/live/filesystem.squashfs"
+const squashfsGlob = "/run/live/medium/live/*.squashfs"
 
 // ListInstallDisks returns block devices suitable for installation.
 // Excludes the current live boot medium but includes USB drives.
@@ -176,11 +177,22 @@ func inferLiveBootKind(fsType, source, deviceType, transport string) string {
 // squashfs size × 1.5 to allow for extracted filesystem and bootloader.
 // Returns 0 if the squashfs is not available (non-live environment).
 func MinInstallBytes() int64 {
-	fi, err := os.Stat(squashfsPath)
-	if err != nil {
+	files, err := filepath.Glob(squashfsGlob)
+	if err != nil || len(files) == 0 {
 		return 0
 	}
-	return fi.Size() * 3 / 2
+	var total int64
+	for _, path := range files {
+		fi, statErr := os.Stat(path)
+		if statErr != nil {
+			continue
+		}
+		total += fi.Size()
+	}
+	if total == 0 {
+		return 0
+	}
+	return total * 3 / 2
 }
 
 // toramActive returns true when the live system was booted with toram.
@@ -222,12 +234,10 @@ func DiskWarnings(d InstallDisk) []string {
 			humanBytes(min), humanBytes(d.SizeBytes)))
 	}
 	if toramActive() {
-		sqFi, err := os.Stat(squashfsPath)
-		if err == nil {
-			free := freeMemBytes()
-			if free > 0 && free < sqFi.Size()*2 {
-				w = append(w, "toram mode — low RAM, extraction may be slow or fail")
-			}
+		free := freeMemBytes()
+		min := MinInstallBytes()
+		if free > 0 && min > 0 && free < (min*4/3) {
+			w = append(w, "toram mode — low RAM, extraction may be slow or fail")
 		}
 	}
 	return w