Fix handling of mount points with white space (#186713):

- src/fstab-decode.c, src/fstab-decode.8: New files.
- src/Makefile: Build and install fstab-decode.
- initscripts.spec: Add fstab-decode to %files
- rc.d/init.d/functions (fstab_decode_str): New function.
  (__umount_loop, __umount_loopback_loop): Factor out from copy&pasted copies.
  (action): Fix command quoting.
- rc.d/rc.sysinit: Correctly quote and decode mount points.
- rc.d/init.d/halt: Use __umount_* and fstab-decode.
  (action): Rename from runcmd.  Fix command quoting.
- rc.d/init.d/netfs: Use __umount_*.

8 files changed, 247 insertions, 160 deletions

diff --git a/initscripts.spec b/initscripts.spec
index de6cd80b..3d8129ac 100644
--- a/initscripts.spec
+++ b/initscripts.spec
@@ -188,6 +188,7 @@ rm -rf $RPM_BUILD_ROOT
 /bin/usleep
 %attr(4755,root,root) /usr/sbin/usernetctl
 /sbin/consoletype
+/sbin/fstab-decode
 /sbin/genhostid
 /sbin/getkey
 %attr(2755,root,root) /sbin/netreport
diff --git a/rc.d/init.d/functions b/rc.d/init.d/functions
index 74fd3d05..f1844d54 100755
--- a/rc.d/init.d/functions
+++ b/rc.d/init.d/functions
@@ -68,6 +68,11 @@ else
    INITLOG_ARGS=
 fi
 
+# Interpret escape sequences in an fstab entry
+fstab_decode_str() {
+	fstab-decode echo "$1"
+}
+
 # Check if $pid (could be plural) are running
 checkpid() {
 	local i
@@ -78,6 +83,60 @@ checkpid() {
 	return 1
 }
 
+# __umount_loop awk_program fstab_file first_msg retry_msg umount_args
+# awk_program should process fstab_file and return a list of fstab-encoded
+# paths; it doesn't have to handle comments in fstab_file.
+__umount_loop() {
+	local remaining sig=
+	local retry=3
+
+	remaining=$(LC_ALL=C awk "/^#/ {next} $1" "$2" | sort -r)
+	while [ -n "$remaining" -a "$retry" -gt 0 ]; do
+		if [ "$retry" -eq 3 ]; then
+			action "$3" fstab-decode umount $5 $remaining
+		else
+			action "$4" fstab-decode umount $5 $remaining
+		fi
+		sleep 2
+		remaining=$(LC_ALL=C awk "/^#/ {next} $1" "$2" | sort -r)
+		[ -z "$remaining" ] && break
+		fstab-decode /sbin/fuser -k -m $sig $remaining >/dev/null
+		sleep 5
+		retry=$(($retry -1))
+		sig=-9
+	done
+}
+
+# Similar to __umount loop above, specialized for loopback devices
+__umount_loopback_loop() {
+	local remaining devremaining sig=
+	local retry=3
+
+	remaining=$(awk '$1 ~ /^\/dev\/loop/ && $2 != "/" {print $2}' /proc/mounts)
+	devremaining=$(awk '$1 ~ /^\/dev\/loop/ && $2 != "/" {print $1}' /proc/mounts)
+	while [ -n "$remaining" -a "$retry" -gt 0 ]; do
+		if [ "$retry" -eq 3 ]; then
+			action $"Unmounting loopback filesystems: " \
+				fstab-decode umount $remaining
+		else
+			action $"Unmounting loopback filesystems (retry):" \
+				fstab-decode umount $remaining
+		fi
+		for dev in $devremaining ; do
+			losetup $dev > /dev/null 2>&1 && \
+				action $"Detaching loopback device $dev: " \
+				losetup -d $dev
+		done
+		remaining=$(awk '$1 ~ /^\/dev\/loop/ && $2 != "/" {print $2}' /proc/mounts)
+		devremaining=$(awk '$1 ~ /^\/dev\/loop/ && $2 != "/" {print $1}' /proc/mounts)
+		[ -z "$remaining" ] && break
+		fstab-decode /sbin/fuser -k -m $sig $remaining >/dev/null
+		sleep 5
+		retry=$(($retry -1))
+		sig=-9
+	done
+}
+
 # __proc_pids {program} [pidfile]
 # Set $pid to pids from /var/run* for {program}.  $pid should be declared
 # local in the caller.
@@ -442,7 +501,7 @@ action() {
       echo -n "$STRING " > /etc/rhgb/temp/rhgb-console
   fi
   shift
-  $* && success $"$STRING" || failure $"$STRING"
+  "$@" && success $"$STRING" || failure $"$STRING"
   rc=$?
   echo
   if [ "${RHGB_STARTED:-}" != "" -a -w /etc/rhgb/temp/rhgb-console ]; then
diff --git a/rc.d/init.d/halt b/rc.d/init.d/halt
index 25fba6f7..d1ff19bf 100755
--- a/rc.d/init.d/halt
+++ b/rc.d/init.d/halt
@@ -11,24 +11,17 @@
 NOLOCALE=1
 . /etc/init.d/functions
 
-runcmd() {
+action() {
    echo -n "$1 "
    shift
    if [ "$BOOTUP" = "color" ]; then
-      $* && echo_success || echo_failure
+      "$@" && echo_success || echo_failure
    else
-      $*
+      "$@"
    fi
    echo
 }
 
-halt_get_remaining() {
-	awk '$2 ~ /^\/$|^\/proc|^\/dev/{next}
-	     $3 == "tmpfs" || $3 == "proc" {print $2 ; next}
-	     /(^#|loopfs|autofs|sysfs|^none|^\/dev\/ram|^\/dev\/root)/ {next}
-	     {print $2}' /proc/mounts
-}
-
 # See how we were called.
 case "$0" in
    *halt)
@@ -57,9 +50,9 @@ esac
 # Kill all processes.
 [ "${BASH+bash}" = bash ] && enable kill
 
-runcmd $"Sending all processes the TERM signal..." /sbin/killall5 -15
+action $"Sending all processes the TERM signal..." /sbin/killall5 -15
 sleep 5
-runcmd $"Sending all processes the KILL signal..."  /sbin/killall5 -9
+action $"Sending all processes the KILL signal..."  /sbin/killall5 -9
 
 # Write to wtmp file before unmounting /var
 /sbin/halt -w
@@ -67,13 +60,13 @@ runcmd $"Sending all processes the KILL signal..."  /sbin/killall5 -9
 # Save mixer settings, here for lack of a better place.
 grep -q "\(alsa\)" /proc/devices
 if [ $? = 0 -a -x /usr/sbin/alsactl ]; then
-   runcmd $"Saving mixer settings" alsactl store
+   action $"Saving mixer settings" alsactl store
 fi
 
 # Save random seed
 touch /var/lib/random-seed
 chmod 600 /var/lib/random-seed
-runcmd $"Saving random seed: " dd if=/dev/urandom of=/var/lib/random-seed count=1 bs=512 2>/dev/null
+action $"Saving random seed: " dd if=/dev/urandom of=/var/lib/random-seed count=1 bs=512 2>/dev/null
 
 # Sync the system clock.
 ARC=0
@@ -118,87 +111,38 @@ case "$SRM" in
 	;;
 esac
 
-runcmd $"Syncing hardware clock to system time" /sbin/hwclock $CLOCKFLAGS
+action $"Syncing hardware clock to system time" /sbin/hwclock $CLOCKFLAGS
 
 # Try to unmount tmpfs filesystems to avoid swapping them in.  Ignore failures.
 tmpfs=$(awk '$2 ~ /^\/($|proc|dev)/ { next; }
 	     $3 == "tmpfs" { print $2; }' /proc/mounts | sort -r)
-[ -n "$tmpfs" ] && umount $tmpfs 2>/dev/null
+[ -n "$tmpfs" ] && fstab-decode umount $tmpfs 2>/dev/null
 
 # Turn off swap, then unmount file systems.
 [ -f /proc/swaps ] && SWAPS=`awk '! /^Filename/ { print $1 }' /proc/swaps`
-[ -n "$SWAPS" ] && runcmd $"Turning off swap: " swapoff $SWAPS
+[ -n "$SWAPS" ] && action $"Turning off swap: " swapoff $SWAPS
 
-[ -x /sbin/quotaoff ] && runcmd $"Turning off quotas: " /sbin/quotaoff -aug
+[ -x /sbin/quotaoff ] && action $"Turning off quotas: " /sbin/quotaoff -aug
 
 # Unmount file systems, killing processes if we have to.
 # Unmount loopback stuff first
-remaining=`awk '$1 ~ /^\/dev\/loop/ && $2 != "/" {print $2}' /proc/mounts`
-devremaining=`awk '$1 ~ /^\/dev\/loop/ && $2 != "/" {print $1}' /proc/mounts`
-[ -n "$remaining" ] && {
-	sig=
-	retry=3
-	while [ -n "$remaining" -a "$retry" -gt 0 ]
-	do
-		if [ "$retry" -lt 3 ]; then
-			runcmd $"Unmounting loopback filesystems (retry):" umount $remaining
-		else
-			runcmd $"Unmounting loopback filesystems: " umount $remaining
-		fi
-		for dev in $devremaining ; do
-			losetup $dev > /dev/null 2>&1 && \
-				runcmd $"Detaching loopback device $dev: " losetup -d $dev
-		done
-		remaining=`awk '$1 ~ /^\/dev\/loop/ && $2 != "/" {print $2}' /proc/mounts`
-		devremaining=`awk '$1 ~ /^\/dev\/loop/ && $2 != "/" {print $1}' /proc/mounts`
-		[ -z "$remaining" ] && break
-		/sbin/fuser -k -m $sig $remaining >/dev/null
-		sleep 5
-		retry=$(($retry -1))
-		sig=-9
-	done
-}
+__umount_loopback_loop
 
 # Unmount RPC pipe file systems
-sig=
-retry=3
-remaining=`awk '$3 ~ /^rpc_pipefs$/ || $3 ~ /^rpc_svc_gss_pipefs$/ {print $2}' /proc/mounts`
-
-while [ -n "$remaining" -a "$retry" -gt 0 ]
-do
-	if [ "$retry" -lt 3 ]; then
-		runcmd $"Unmounting pipe file systems (retry): "  umount -f $remaining
-	else
-		runcmd $"Unmounting pipe file systems: "  umount -f $remaining
-	fi
-	sleep 2
-	remaining=`awk '$3 ~ /^rpc_pipefs$/ || $3 ~ /^rpc_svc_gss_pipefs$/ {print $2}' /proc/mounts`
-	[ -z "$remaining" ] && break
-	/sbin/fuser -k -m $sig $remaining >/dev/null
-	sleep 5
-	retry=$(($retry-1))
-	sig=-9
-done
-
-sig=
-retry=3
-remaining=`halt_get_remaining | sort -r`
+__umount_loop '$3 ~ /^rpc_pipefs$/ || $3 ~ /^rpc_svc_gss_pipefs$/ {print $2}' \
+    /proc/mounts \
+    $"Unmounting pipe file systems: " \
+    $"Unmounting pipe file systems (retry): " \
+    -f
+
+LANG=C __umount_loop '$2 ~ /^\/$|^\/proc|^\/dev/{next}
+	$3 == "tmpfs" || $3 == "proc" {print $2 ; next}
+	/(loopfs|autofs|sysfs|^none|^\/dev\/ram|^\/dev\/root)/ {next}
+	{print $2}' /proc/mounts \
+	$"Unmounting file systems: " \
+	$"Unmounting file systems (retry): " \
+	-f
 
-while [ -n "$remaining" -a "$retry" -gt 0 ]
-do
-	if [ "$retry" -lt 3 ]; then
-		LANG=C runcmd $"Unmounting file systems (retry): "  umount -f $remaining
-	else
-		LANG=C runcmd $"Unmounting file systems: "  umount -f $remaining
-	fi
-	sleep 2
-	remaining=`halt_get_remaining | sort -r`
-	[ -z "$remaining" ] && break
-	/sbin/fuser -k -m $sig $remaining >/dev/null
-	sleep 5
-	retry=$(($retry-1))
-	sig=-9
-done
 [ -f /proc/bus/usb/devices ] && umount /proc/bus/usb
 
 # remove the crash indicator flag
@@ -207,7 +151,7 @@ rm -f /.autofsck
 # Try all file systems other than root and RAM disks, one last time.
 mount |  awk '!/( \/ |^\/dev\/root|^\/dev\/ram| \/proc )/ { print $3 }' | sort -r | \
   while read line; do
-    umount -f $line
+    fstab-decode umount -f $line
 done
 
 if [ -x /sbin/halt.local ]; then
@@ -217,7 +161,7 @@ fi
 # Remount read only anything that's left mounted.
 # echo $"Remounting remaining filesystems readonly"
 mount | awk '{ print $3 }' | while read line; do
-    mount -n -o ro,remount $line
+    fstab-decode mount -n -o ro,remount $line
 done
 
 # Now halt or reboot.
diff --git a/rc.d/init.d/netfs b/rc.d/init.d/netfs
index faab107e..59693d11 100755
--- a/rc.d/init.d/netfs
+++ b/rc.d/init.d/netfs
@@ -89,71 +89,20 @@ case "$1" in
 	;;
   stop)
         # Unmount loopback stuff first
-	remaining=`LC_ALL=C awk '$1 ~ /^\/dev\/loop/ && $2 != "/" {print $2}' /proc/mounts`
-	devremaining=`LC_ALL=C awk '$1 ~ /^\/dev\/loop/ && $2 != "/" {print $1}' /proc/mounts`
-	[ -n "$remaining" ] && {
-	        sig=
-		retry=3
-		while [ -n "$remaining" -a "$retry" -gt 0 ]
-		do
-			if [ "$retry" -lt 3 ]; then
-				action $"Unmounting loopback filesystems (retry):" umount $remaining
-			else
-				action $"Unmounting loopback filesystems: " umount $remaining
-		        fi
-			for dev in $devremaining ; do
-				losetup $dev >/dev/null 2>&1 && \
-				action $"Detaching loopback device $dev: " losetup -d $dev
-			done	
-			remaining=`LC_ALL=C awk '$1 ~ /^\/dev\/loop/ && $2 != "/" {print $2}' /proc/mounts`
-			devremaining=`LC_ALL=C awk '$1 ~ /^\/dev\/loop/ && $2 != "/" {print $1}' /proc/mounts`
-			[ -z "$remaining" ] && break
-			/sbin/fuser -k -m $sig $remaining >/dev/null
-			sleep 5
-			retry=$(($retry -1))
-			sig=-9
-		done
-	}
-  	[ -n "$NETDEVMTAB" ] && {
-		sig=
-		retry=3
-		remaining=`LC_ALL=C awk '!/^#/ && $4 ~ /_netdev/ && $2 != "/" {print $2}' /etc/mtab`
-		while [ -n "$remaining" -a "$retry" -gt 0 ]
-		do
-			if [ "$retry" -lt 3 ]; then
-				action $"Unmounting network block filesystems (retry): " umount -a -O _netdev
-			else
-				action $"Unmounting network block filesystems: " umount -a -O _netdev
-			fi
-			sleep 2
-			remaining=`LC_ALL=C awk '!/^#/ && $4 ~ /_netdev/ && $2 != "/" {print $2}' /etc/mtab`
-			[ -z "$remaining" ] && break
-			/sbin/fuser -k -m $sig $remaining >/dev/null
-			sleep 5
-			retry=$(($retry - 1))
-			sig=-9
-		done
-	}
-  	[ -n "$NFSMTAB" ] && {
-		sig=
-		retry=3
-		remaining=`LC_ALL=C awk '$3 ~ /^nfs/ && $2 != "/" {print $2}' /proc/mounts`
-		while [ -n "$remaining" -a "$retry" -gt 0 ]
-		do
-			if [ "$retry" -lt 3 ]; then
-				action $"Unmounting NFS filesystems (retry): " umount -f -l $remaining
-			else
-				action $"Unmounting NFS filesystems: " umount -f -l $remaining
-			fi
-			sleep 2
-			remaining=`LC_ALL=C awk '$3 ~ /^nfs/ && $2 != "/" {print $2}' /proc/mounts`
-			[ -z "$remaining" ] && break
-			/sbin/fuser -k -m $sig $remaining >/dev/null
-			sleep 5
-			retry=$(($retry - 1))
-			sig=-9
-		done
-	}
+	__umount_loopback_loop
+  	if [ -n "$NETDEVMTAB" ]; then
+		__umount_loop '$4 ~ /_netdev/ && $2 != "/" {print $2}' \
+			/etc/mtab \
+			$"Unmounting network block filesystems: " \
+			$"Unmounting network block filesystems (retry): "
+	fi
+  	if [ -n "$NFSMTAB" ]; then
+		__umount_loop '$3 ~ /^nfs/ && $2 != "/" {print $2}' \
+			/proc/mounts \
+			$"Unmounting NFS filesystems: " \
+			$"Unmounting NFS filesystems (retry): " \
+			"-f -l"
+	fi
 	[ -n "$SMBMTAB" ] && action $"Unmounting SMB filesystems: " umount -a -t smbfs
 	[ -n "$CIFSMTAB" ] && action $"Unmounting CIFS filesystems: " umount -a -t cifs
 	[ -n "$NCPMTAB" ] && action $"Unmounting NCP filesystems: " umount -a -t ncpfs
diff --git a/rc.d/rc.sysinit b/rc.d/rc.sysinit
index 96e79c82..c0195319 100755
--- a/rc.d/rc.sysinit
+++ b/rc.d/rc.sysinit
@@ -29,11 +29,11 @@ fi
 . /etc/init.d/functions
 
 # Check SELinux status
-selinuxfs=`LC_ALL=C awk '/ selinuxfs / { print $2 }' /proc/mounts`
+selinuxfs="$(fstab_decode_str `LC_ALL=C awk '/ selinuxfs / { print $2 }' /proc/mounts`)"
 SELINUX_STATE=
 if [ -n "$selinuxfs" ] && [ "`cat /proc/self/attr/current`" != "kernel" ]; then
-	if [ -r $selinuxfs/enforce ] ; then
-		SELINUX_STATE=`cat $selinuxfs/enforce`
+	if [ -r "$selinuxfs/enforce" ] ; then
+		SELINUX_STATE=`cat "$selinuxfs/enforce"`
 	else
 		# assume enforcing if you can't read it
 		SELINUX_STATE=1
@@ -48,7 +48,7 @@ disable_selinux() {
 	echo "*** Warning -- SELinux is active"
 	echo "*** Disabling security enforcement for system recovery."
 	echo "*** Run 'setenforce 1' to reenable."
-	echo "0" > $selinuxfs/enforce
+	echo "0" > "$selinuxfs/enforce"
 }
 
 relabel_selinux() {
@@ -64,14 +64,14 @@ relabel_selinux() {
          *** Relabelling could take a very long time, depending on file    ***
          *** system size and speed of hard drives.                         ***
 	 "
-    echo "0" > $selinuxfs/enforce
+    echo "0" > "$selinuxfs/enforce"
     /sbin/fixfiles restore > /dev/null 2>&1 
     rm -f  /.autorelabel 
     if [ ! -z "$REBOOTFLAG" ]; then 
 		echo $"Automatic reboot in progress."
 		reboot -f
     fi
-    echo $SELINUX_STATE > $selinuxfs/enforce
+    echo $SELINUX_STATE > "$selinuxfs/enforce"
     if [ -x /usr/bin/rhgb-client ] && /usr/bin/rhgb-client --ping ; then
 	chvt 8
     fi
@@ -431,15 +431,16 @@ if [ X"$_RUN_QUOTACHECK" = X1 -a -x /sbin/quotacheck ]; then
 	if [ -x /sbin/convertquota ]; then
 	    # try to convert old quotas
 	    for mountpt in `LC_ALL=C awk '$4 ~ /quota/{print $2}' /etc/mtab` ; do
+	        mountpt="$(fstab_decode_str "$mountpt")"
 		if [ -f "$mountpt/quota.user" ]; then
 		    action $"Converting old user quota files: " \
-		    /sbin/convertquota -u $mountpt && \
-			rm -f $mountpt/quota.user
+		    /sbin/convertquota -u "$mountpt" && \
+			rm -f "$mountpt/quota.user"
 		fi
 		if [ -f "$mountpt/quota.group" ]; then
 		    action $"Converting old group quota files: " \
-		    /sbin/convertquota -g $mountpt && \
-			rm -f $mountpt/quota.group
+		    /sbin/convertquota -g "$mountpt" && \
+			rm -f "$mountpt/quota.group"
 		fi
 	    done
 	fi
diff --git a/src/Makefile b/src/Makefile
index 78276fad..84d6d439 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -1,7 +1,7 @@
 CFLAGS+=$(RPM_OPT_FLAGS) -Wall -D_GNU_SOURCE
 
 PROGS=usernetctl doexec netreport testd usleep ipcalc initlog \
-	getkey ppp-watch consoletype genhostid rename_device
+	fstab-decode getkey ppp-watch consoletype genhostid rename_device
 PPPWATCH_OBJS=ppp-watch.o shvar.o
 INITLOG_OBJS=initlog.o process.o
 USLEEP_OBJS=usleep.o
@@ -20,6 +20,7 @@ install:
 	install -m 4755 usernetctl $(ROOT)/usr/sbin/usernetctl
 	install -m 2755 netreport $(ROOT)/sbin/netreport
 	install -m 755 ipcalc $(ROOT)/bin/ipcalc
+	install -m 755 fstab-decode $(ROOT)/sbin/fstab-decode
 	install -m 755 genhostid $(ROOT)/sbin/genhostid
 	install -m 755 initlog $(ROOT)/sbin/initlog
 	install -m 755 getkey $(ROOT)/sbin/getkey
@@ -32,6 +33,7 @@ install:
 	install -m 644 getkey.1 $(ROOT)$(mandir)/man1
 	install -m 644 netreport.1 $(ROOT)$(mandir)/man1
 	install -m 644 usleep.1 $(ROOT)$(mandir)/man1
+	install -m 644 fstab-decode.8 $(ROOT)$(mandir)/man8
 	install -m 644 usernetctl.8 $(ROOT)$(mandir)/man8
 	install -m 644 ppp-watch.8 $(ROOT)$(mandir)/man8
 	install -m 644 ipcalc.1 $(ROOT)$(mandir)/man1
diff --git a/src/fstab-decode.8 b/src/fstab-decode.8
new file mode 100644
index 00000000..216dee86
--- /dev/null
+++ b/src/fstab-decode.8
@@ -0,0 +1,45 @@
+.\" A man page for fstab-decode(8).
+.\"
+.\" Copyright (C) 2006 Red Hat, Inc. All rights reserved.
+.\"
+.\" This copyrighted material is made available to anyone wishing to use,
+.\" modify, copy, or redistribute it subject to the terms and conditions of the
+.\" GNU General Public License v.2.
+.\"
+.\" This program is distributed in the hope that it will be useful, but WITHOUT
+.\" ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 
+.\" FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 
+.\" more details.
+.\"
+.\" You should have received a copy of the GNU General Public License along
+.\" with this program; if not, write to the Free Software Foundation, Inc.,
+.\" 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+.\"
+.\" Author: Miloslav Trmac <mitr@redhat.com>
+.TH fstab-decode 8 "May 2006"
+
+.SH NAME
+fstab-decode \- run a command with fstab-encoded arguments
+
+.SH SYNOPSIS
+\fB fstab-decode\fR \fICOMMAND\fR [\fIARGUMENT\fR]...
+
+.SH DESCRIPTION
+.B fstab-decode
+decodes escapes in the specified \FIARGUMENT\fRs
+and uses them to run \fICOMMAND\fR.
+The argument escaping uses the same rules as path escaping in
+\fB/etc/fstab\fR,
+.B /etc/mtab
+and \fB/proc/mtab\fR.
+
+.SH EXIT STATUS
+.B fstab-decode
+exits with status 127 if
+.I COMMAND
+can't be run.
+Otherwise it exits with the status returned by \fICOMMAND\fR.
+
+.SH EXAMPLES
+
+.B fstab-decode umount $(awk '$3 == "vfat" { print $2 }' /etc/fstab)
diff --git a/src/fstab-decode.c b/src/fstab-decode.c
new file mode 100644
index 00000000..4a162dfe
--- /dev/null
+++ b/src/fstab-decode.c
@@ -0,0 +1,86 @@
+/* fstab-decode(8).
+
+Copyright (c) 2006 Red Hat, Inc. All rights reserved.
+
+This copyrighted material is made available to anyone wishing to use, modify,
+copy, or redistribute it subject to the terms and conditions of the GNU General
+Public License v.2.
+
+This program is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+PARTICULAR PURPOSE. See the GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with
+this program; if not, write to the Free Software Foundation, Inc., 51 Franklin
+Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
+Author: Miloslav Trmac <mitr@redhat.com> */
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+/* Decode the fstab-encoded string in place. */
+static void
+decode(char *s)
+{
+	const char *src;
+	char *dest;
+
+	src = s;
+	dest = s;
+	while (*src != '\0') {
+		if (*src != '\\')
+			*dest = *src++;
+		else {
+			static const struct repl {
+				char orig[4];
+				size_t len;
+				char new;
+			} repls[] = {
+#define R(X, Y) { X, sizeof(X) - 1, Y }
+				R("\\", '\\'),
+				R("011", '\t'),
+				R("012", '\n'),
+				R("040", ' '),
+				R("134", '\\')
+#undef R
+			};
+
+			size_t i;
+
+			for (i = 0; i < sizeof (repls) / sizeof (repls[0]);
+			     i++) {
+				if (memcmp(src + 1, repls[i].orig,
+					   repls[i].len) == 0) {
+					*dest = repls[i].new;
+					src += 1 + repls[i].len;
+					goto found;
+				}
+			}
+			*dest = *src++;
+		found:
+			;
+		}
+		dest++;
+	}
+	*dest = '\0';
+}
+
+int
+main (int argc, char *argv[])
+{
+	size_t i;
+
+	if (argc < 2) {
+		fprintf(stderr, "Usage: fstab-decode command [arguments]\n");
+		return EXIT_FAILURE;
+	}
+	for (i = 2; i < (size_t)argc; i++)
+		decode(argv[i]);
+	execvp(argv[1], argv + 1);
+	fprintf(stderr, "fstab-decode: %s: %s\n", argv[1], strerror(errno));
+	return 127;
+}