From 66a5308d2e8f61093716a076f4386416dc18045c Mon Sep 17 00:00:00 2001
From: Oyvind Albrigtsen <oalbrigt@redhat.com>
Date: Mon, 22 Apr 2024 11:26:09 +0200
Subject: [PATCH] Filesystem: fail when incorrect device mounted on mountpoint,
 and dont unmount the mountpoint in this case, or if mountpoint set to "/"

---
 heartbeat/Filesystem | 71 ++++++++++++++++++++++++++++++++++++--------
 1 file changed, 58 insertions(+), 13 deletions(-)

diff --git a/heartbeat/Filesystem b/heartbeat/Filesystem
index e1378f781..cec71f1a6 100755
--- a/heartbeat/Filesystem
+++ b/heartbeat/Filesystem
@@ -582,10 +582,16 @@ Filesystem_start()
 	fi
 
 	# See if the device is already mounted.
-	if Filesystem_status >/dev/null 2>&1 ; then
-		ocf_log info "Filesystem $MOUNTPOINT is already mounted."
-		return $OCF_SUCCESS
-	fi
+	Filesystem_status
+	case "$?" in
+		$OCF_SUCCESS)
+			ocf_log info "Filesystem $MOUNTPOINT is already mounted."
+			return $OCF_SUCCESS
+			;;
+		$OCF_ERR_CONFIGURED)
+			return $OCF_ERR_CONFIGURED
+			;;
+	esac
 
 	fstype_supported || exit $OCF_ERR_INSTALLED
 
@@ -801,10 +807,42 @@ Filesystem_stop()
 #
 Filesystem_status()
 {
-	match_string="${TAB}${CANONICALIZED_MOUNTPOINT}${TAB}"
-	if list_mounts | grep "$match_string" >/dev/null 2>&1; then
-		rc=$OCF_SUCCESS
-		msg="$MOUNTPOINT is mounted (running)"
+	local match_string="${TAB}${CANONICALIZED_MOUNTPOINT}${TAB}"
+	local mounted_device=$(list_mounts | grep "$match_string" | awk '{print $1}')
+
+	if [ -n "$mounted_device" ]; then
+		if [ "X$blockdevice" = "Xyes" ]; then
+			if [ -e "$DEVICE" ] ; then
+				local canonicalized_device="$(readlink -f "$DEVICE")"
+				if [ $? -ne 0 ]; then
+					ocf_exit_reason "Could not canonicalize $DEVICE because readlink failed"
+					exit $OCF_ERR_GENERIC
+				fi
+			else
+				local canonicalized_device="$DEVICE"
+			fi
+			if [ -e "$mounted_device" ] ; then
+				local canonicalized_mounted_device="$(readlink -f "$mounted_device")"
+				if [ $? -ne 0 ]; then
+					ocf_exit_reason "Could not canonicalize $mounted_device because readlink failed"
+					exit $OCF_ERR_GENERIC
+				fi
+			else
+				local canonicalized_mounted_device="$mounted_device"
+			fi
+			if [ "$canonicalized_device" != "$canonicalized_mounted_device" ]; then
+				if ocf_is_probe || [ "$__OCF_ACTION" = "stop" ]; then
+					ocf_log debug "Another device ($mounted_device) is already mounted on $MOUNTPOINT"
+					rc=$OCF_NOT_RUNNING
+				else
+					ocf_exit_reason "Another device ($mounted_device) is already mounted on $MOUNTPOINT"
+					rc=$OCF_ERR_CONFIGURED
+				fi
+			fi
+		else
+			rc=$OCF_SUCCESS
+			msg="$MOUNTPOINT is mounted (running)"
+		fi
 	else
 		rc=$OCF_NOT_RUNNING
 		msg="$MOUNTPOINT is unmounted (stopped)"
@@ -1041,9 +1079,18 @@ else
 	else
 		CANONICALIZED_MOUNTPOINT="$MOUNTPOINT"
 	fi
-	# At this stage, $MOUNTPOINT does not contain trailing "/" unless it is "/"
-	# TODO: / mounted via Filesystem sounds dangerous. On stop, we'll
-	# kill the whole system. Is that a good idea?
+
+	if echo "$CANONICALIZED_MOUNTPOINT" | grep -q "^\s*/\s*$"; then
+		if ocf_is_probe; then
+			ocf_log debug "/ cannot be managed in a cluster"
+			exit $OCF_NOT_RUNNING
+		elif [ "$__OCF_ACTION" = "start" ] || [ "$__OCF_ACTION" = "monitor" ] || [ "$__OCF_ACTION" = "status" ]; then
+			ocf_exit_reason "/ cannot be managed in a cluster"
+			exit $OCF_ERR_CONFIGURED
+		elif [ "$__OCF_ACTION" = "stop" ]; then
+			exit $OCF_SUCCESS
+		fi
+	fi
 fi
 
 # Check to make sure the utilites are found
@@ -1124,5 +1171,3 @@ case $OP in
 		;;
 	esac
 exit $?
-
-