Core Update 167: Replace /etc/mtab by symlink to /proc/self/mounts

mount, as updated via util-linux, no longer writes /etc/mtab, causing
programs to rely on this file's content (such as the check_disk Nagios
plugin) to stop working.

/proc/self/mounts contains all the necessary information, so it is fine
to replace /etc/mtab by a symlink to it.

Fixes: #12843

Signed-off-by: Peter Müller <peter.mueller@ipfire.org>

config/rootfiles/core/167/filelists/files

@@ -1,7 +1,9 @@
 etc/collectd.conf
 etc/inittab.d
 etc/rc.d/init.d/firewall
+etc/rc.d/init.d/mountfs
 etc/rc.d/init.d/pakfire
+etc/rc.d/init.d/partresize
 etc/sysctl.conf
 lib/udev/network-hotplug-bridges
 srv/web/ipfire/cgi-bin/connections.cgi

config/rootfiles/core/167/update.sh

@@ -386,6 +386,10 @@ hardlink -c -vv /lib/firmware
 # Regenerate all initrds
 dracut --regenerate-all --force
 
+# Replace /etc/mtab by symlink as mount no longer writes it
+rm -vf /etc/mtab
+ln -vs /proc/self/mounts /etc/mtab
+
 # Export the location database again and reload the firewall engine
 /usr/local/bin/update-location-database
 

lfs/stage2

@@ -87,7 +87,8 @@ endif
 	cp -rvf $(DIR_SRC)/config/etc/* /etc;
 	[ ! -d "$(DIR_SRC)/config/etc-$(BUILD_ARCH)" ] || cp -rvf $(DIR_SRC)/config/etc-$(BUILD_ARCH)/* /etc
 	cp -rvf $(DIR_SRC)/config/lib/* /lib;
-	touch /etc/{fs,m}tab
+	touch /etc/fstab
+	ln -s /proc/self/mounts /etc/mtab
 	echo "$(NAME) v$(VERSION) - $(SLOGAN)" >  /etc/issue
 	echo "===============================" >> /etc/issue
 	echo "\n running on \s \r \m"          >> /etc/issue

src/initscripts/system/mountfs

@@ -31,12 +31,6 @@ case "${1}" in
 		# Remove fsck-related file system watermarks.
 		rm -f /fastboot /forcefsck
 
-		boot_mesg "Create /etc/mtab..."
-		> /etc/mtab
-		mount -f / || failed=1
-		(exit ${failed})
-		evaluate_retval
-
 		# This will mount all filesystems that do not have _netdev in
 		# their option list.  _netdev denotes a network filesystem.
 		boot_mesg "Mounting remaining file systems..."

src/initscripts/system/partresize

@@ -30,12 +30,6 @@ case "${1}" in
 			mount -o remount,rw / > /dev/null
 			evaluate_retval
 
-			boot_mesg "Create /etc/mtab..."
-			> /etc/mtab
-			mount -f / || failed=1
-			(exit ${failed})
-			evaluate_retval
-
 			# check if serial console enabled
 			scon="off";
 			if [ ! "$(grep "console=ttyS0" /proc/cmdline)" == "" ]; then