Fix: incorrect system version information retrieved from mounted disks

common.sh

@@ -296,3 +296,12 @@ linux_mount_boot () {
 
 	mountboot="$bootpart $mounted"
 }
+
+is_efi_stub() {
+  _file=$1
+  if [ -f "$_file" ] && [ "MZ" = "$(head --bytes=2 "$_file")" ]; then
+	  return 0
+  else
+	  return 1
+  fi
+}

debian/changelog

@@ -1,3 +1,9 @@
+os-prober (1.82+deepin3) unstable; urgency=medium
+
+  * Fix incorrect system version information retrieved from mounted disks.
+
+ -- xinpeng.wang <wangxinpeng@uniontech.com>  Fri, 31 Oct 2025 11:42:56 +0800
+
 os-prober (1.82+deepin2) unstable; urgency=medium
 
   * feat: add sw64 support.

debian/patches/series

@@ -1 +1,2 @@
 0001-feat-linux-boot-probes-detect-old-world-kernels-and-.patch
+uniontech-fix-error-version-for-mounted.patch

debian/patches/uniontech-fix-error-version-for-mounted.patch

@@ -0,0 +1,32 @@
+Index: deepin-os-prober/os-prober
+===================================================================
+--- deepin-os-prober.orig/os-prober	2025-10-31 11:28:54.138808288 +0800
++++ deepin-os-prober/os-prober	2025-10-31 11:42:38.873689779 +0800
+@@ -161,6 +161,27 @@
+ 	else
+ 		mpoint=$(grep "^$mapped " "$OS_PROBER_TMP/mounted-map" | head -n1 | cut -d " " -f 2)
+ 		mpoint="$(unescape_mount "$mpoint")"
++
++		# This resolves the issue of incorrect system version information retrieved from mounted disks.
++		# The problem stems from symbolic links within mounted partitions pointing to the local root
++		# directory, leading to incorrect version readings. Treating these disks as unmounted and
++		# remounting them using `grub-mount` resolves the issue, resulting in the correct version
++		# information.
++		if [ -n "$OS_PROBER_NEWNS" ] && { [ "${mpoint#/mnt/}" != "$mpoint" ] || [ "${mpoint#/media/}" != "$mpoint" ]; }; then
++        	debug "using unmounted detection for newns partition: $partition at $mpoint"
++
++        	for test in /usr/lib/os-probes/*; do
++            	if [ -f "$test" ] && [ -x "$test" ]; then
++                	debug "running $test on $partition (newns safe mode)"
++                	if "$test" "$partition"; then
++                    	debug "os detected by $test"
++                    	break
++                	fi
++            	fi
++        	done
++			continue
++		fi
++
+ 		if [ "$mpoint" != "/target/boot" ] && [ "$mpoint" != "/target" ] && [ "$mpoint" != "/" ]; then
+ 			type=$(grep "^$mapped " "$OS_PROBER_TMP/mounted-map" | head -n1 | cut -d " " -f 3)
+ 			for test in /usr/lib/os-probes/mounted/*; do

linux-boot-probes/mounted/common/40grub2

@@ -8,11 +8,20 @@ mpoint="$3"
 type="$4"
 
 found_item=0
+is_loong64=0
+
+# The current system from which os-prober is run is a LoongArch system.
+# Marked by 00_flag-loong64.
+if [ -e "$OS_PROBER_TMP/is_loong64" ]; then
+	is_loong64=1
+fi
 
 entry_result () {
 	if [ "$ignore_item" = 0 ] && \
 	   [ -n "$kernel" ] && \
-	   [ -e "$mpoint/$kernel" ]; then
+	   [ -e "$mpoint/$kernel" ] && ( \
+	     [ "$is_loong64" = 0 ] || is_efi_stub "$mpoint/$kernel" \
+	   ); then
 		result "$rootpart:$bootpart:$title:$kernel:$initrd:$parameters"
 		found_item=1
 	fi

linux-boot-probes/mounted/common/90fallback

@@ -4,6 +4,14 @@
 . /usr/share/os-prober/common.sh
 set -e
 
+is_loong64=0
+
+# The current system from which os-prober is run is a LoongArch system.
+# Marked by 00_flag-loong64.
+if [ -e "$OS_PROBER_TMP/is_loong64" ]; then
+        is_loong64=1
+fi
+
 partition="$1"
 bootpart="$2"
 mpoint="$3"
@@ -22,6 +30,15 @@ for kernpat in /vmlinuz /vmlinux /boot/vmlinuz /boot/vmlinux "/boot/vmlinuz*" \
 	for kernfile in $(eval ls -vr "$mpoint$kernpat" 2>/dev/null); do
 		kernbasefile=$(echo "$kernfile" | sed "s!^$mpoint!!")
 		if [ -f "$kernfile" ] && [ ! -L "$kernfile" ]; then
+			# Detect if the kernel image is non-PE (non-EFI-stub).
+			# Non-EFI-stub kernels can be assumed to be old-world
+			# ones, which needs to be booted from an old-world
+			# GRUB2 bootloader (new-world GRUB2 can't yet boot
+			# old-world kernels.
+			if [ "$is_loong64" = "1" ] && ! is_efi_stub "$kernfile"; then
+				touch "$OS_PROBER_TMP/loong64_have_non_pe_kernel"
+				continue
+			fi
 			initrdname=$(echo "$kernfile" | sed "s/vmlinu[zx]/initrd\*/")
 			# Yellow Dog Linux appends .img to it.
 			initrdname1="${initrdname}.img"

linux-boot-probes/mounted/loong64/00_flag-loong64

@@ -0,0 +1,12 @@
+#!/bin/sh
+
+. /usr/share/os-prober/common.sh
+
+# Mark the current system as a LoongArch (loong64) one.
+#
+# We use this marker to run special routines for detecting old-world kernels
+# and systems to make it possible for users to boot those systems from new-
+# world GRUB2 bootloaders.
+touch "$OS_PROBER_TMP/is_loong64"
+
+exit 1

linux-boot-probes/mounted/loong64/95old-world-grub2

@@ -0,0 +1,55 @@
+#!/bin/sh
+# Locate old-world GRUB2 boot files for chainloading.
+
+. /usr/share/os-prober/common.sh
+
+set -e
+
+partition="$1"
+bootpart="$2"
+mpoint="$3"
+type="$4"
+
+
+exitcode=1
+# In mounted/common/90fallback, we used is_efi_stub to detect non-PE
+# (non-EFI-stub) kernel images to see if the kernel belongs to an old-world
+# system.
+#
+# With LoongArch, the old-world firmware expects to boot from an ELF-formatted
+# kernel image (vmlinu{x,z}), whereas new-world firmware expects PE-formatted
+# EFI stub kernels (vmlinu{x,z}.efi). However, for our purpose, new-world
+# GRUB2 bootloaders are not *yet* able to directly boot old-world kernels, so
+# we take advantage of this format difference to detect old-world systems and
+# simply chainload their bootloaders.
+if [ -e "$OS_PROBER_TMP/loong64_have_non_pe_kernel" ]; then
+	# Usually, $boot_mount/$grub_prefix/$grub_arch/core.efi contains an
+	# EFI GRUB boot image equivalent to that installed in the ESP.
+	#
+	# We use this image for chainloading from a new-world bootloader.
+	for kernpat in \
+		"/grub*/loongarch64-efi/core.efi" \
+		"/boot/grub*/loongarch64-efi/core.efi"; do
+		if echo "$kernpat" | grep -q boot/; then
+			kernbootpart="$bootpart"
+		else
+			kernbootpart="$partition"
+		fi
+		for kernfile in $(eval ls -vr "$mpoint$kernpat" 2>/dev/null); do
+			kernbasefile=$(echo "$kernfile" | sed "s!^$mpoint!!")
+			if [ -f "$kernfile" ] && [ ! -L "$kernfile" ]; then
+				kernrelfile=$kernbasefile
+				if [ "$kernbootpart" != "$partition" ]; then
+					kernrelfile="${kernrelfile#/boot}"
+				fi
+				result "$partition:$kernbootpart::$kernbasefile::; chainloader $kernrelfile"
+				exitcode=0
+				break;
+			fi
+		done
+		if [ "$exitcode" = "0" ]; then
+			break;
+		fi
+	done
+fi
+exit "$exitcode"

os-prober

@@ -161,6 +161,27 @@ for partition in $(partitions); do
 	else
 		mpoint=$(grep "^$mapped " "$OS_PROBER_TMP/mounted-map" | head -n1 | cut -d " " -f 2)
 		mpoint="$(unescape_mount "$mpoint")"
+
+		# This resolves the issue of incorrect system version information retrieved from mounted disks.
+		# The problem stems from symbolic links within mounted partitions pointing to the local root
+		# directory, leading to incorrect version readings. Treating these disks as unmounted and
+		# remounting them using `grub-mount` resolves the issue, resulting in the correct version
+		# information.
+		if [ -n "$OS_PROBER_NEWNS" ] && { [ "${mpoint#/mnt/}" != "$mpoint" ] || [ "${mpoint#/media/}" != "$mpoint" ]; }; then
+        	debug "using unmounted detection for newns partition: $partition at $mpoint"
+
+        	for test in /usr/lib/os-probes/*; do
+            	if [ -f "$test" ] && [ -x "$test" ]; then
+                	debug "running $test on $partition (newns safe mode)"
+                	if "$test" "$partition"; then
+                    	debug "os detected by $test"
+                    	break
+                	fi
+            	fi
+        	done
+			continue
+		fi
+
 		if [ "$mpoint" != "/target/boot" ] && [ "$mpoint" != "/target" ] && [ "$mpoint" != "/" ]; then
 			type=$(grep "^$mapped " "$OS_PROBER_TMP/mounted-map" | head -n1 | cut -d " " -f 3)
 			for test in /usr/lib/os-probes/mounted/*; do