From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Martin Wilck <mwilck@suse.com>
Date: Wed, 16 Dec 2020 23:14:59 +0100
Subject: [PATCH] multipath-tools: make sure plugin DSOs use symbol versions

By adding -Wl,-z,defs, we'll get warnings about unresolved symbols
at the linking stage. This way we make sure our plugins (checkers etc.)
will use versioned symbols from libmultipath, and incompatible plugins
can't be loaded any more. Doing this requires explicitly linking
the plugins with all libraries they use, in particular libmultipath.

Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
---
 Makefile                           | 1 +
 Makefile.inc                       | 2 +-
 libmpathpersist/Makefile           | 8 ++++----
 libmultipath/checkers/Makefile     | 7 +++----
 libmultipath/foreign/Makefile      | 4 +++-
 libmultipath/prioritizers/Makefile | 7 +++----
 6 files changed, 15 insertions(+), 14 deletions(-)

diff --git a/Makefile b/Makefile
index f127ff91..bddb2bf7 100644
--- a/Makefile
+++ b/Makefile
@@ -31,6 +31,7 @@ $(BUILDDIRS):
 
 libmultipath libdmmp: libmpathcmd
 libmpathpersist libmpathvalid multipath multipathd: libmultipath
+libmultipath/prioritizers libmultipath/checkers libmultipath/foreign: libmultipath
 mpathpersist multipathd:  libmpathpersist
 
 libmultipath/checkers.install \
diff --git a/Makefile.inc b/Makefile.inc
index 13587a9f..05429307 100644
--- a/Makefile.inc
+++ b/Makefile.inc
@@ -105,7 +105,7 @@ CFLAGS		:= --std=gnu99 $(CFLAGS) $(OPTFLAGS) $(WARNFLAGS) -pipe \
 BIN_CFLAGS	= -fPIE -DPIE
 LIB_CFLAGS	= -fPIC
 SHARED_FLAGS	= -shared
-LDFLAGS		:= $(LDFLAGS) -Wl,-z,relro -Wl,-z,now
+LDFLAGS		:= $(LDFLAGS) -Wl,-z,relro -Wl,-z,now -Wl,-z,defs
 BIN_LDFLAGS	= -pie
 
 # Check whether a function with name $1 has been declared in header file $2.
diff --git a/libmpathpersist/Makefile b/libmpathpersist/Makefile
index 456ce4cf..57103e58 100644
--- a/libmpathpersist/Makefile
+++ b/libmpathpersist/Makefile
@@ -6,17 +6,17 @@ LIBS = $(DEVLIB).$(SONAME)
 VERSION_SCRIPT := libmpathpersist.version
 
 CFLAGS += $(LIB_CFLAGS) -I$(multipathdir) -I$(mpathpersistdir) -I$(mpathcmddir)
+LDFLAGS += -L$(multipathdir) -L$(mpathcmddir)
 
-LIBDEPS += -lpthread -ldevmapper -ldl -L$(multipathdir) -lmultipath \
-	   -L$(mpathcmddir) -lmpathcmd
+LIBDEPS += -lmultipath -lmpathcmd -ldevmapper -lpthread -ldl
 
 OBJS = mpath_persist.o mpath_updatepr.o mpath_pr_ioctl.o
 
 all: $(DEVLIB) man
 
 $(LIBS): $(OBJS) $(VERSION_SCRIPT)
-	$(CC) $(LDFLAGS) $(SHARED_FLAGS) $(LIBDEPS) -Wl,-soname=$@ \
-		-Wl,--version-script=$(VERSION_SCRIPT) -o $@ $(OBJS)
+	$(CC) $(LDFLAGS) $(SHARED_FLAGS) -Wl,-soname=$@ \
+		-Wl,--version-script=$(VERSION_SCRIPT) -o $@ $(OBJS) $(LIBDEPS)
 
 $(DEVLIB): $(LIBS)
 	$(LN) $(LIBS) $@
diff --git a/libmultipath/checkers/Makefile b/libmultipath/checkers/Makefile
index 01c04510..8e0ed5e9 100644
--- a/libmultipath/checkers/Makefile
+++ b/libmultipath/checkers/Makefile
@@ -4,6 +4,8 @@
 include ../../Makefile.inc
 
 CFLAGS += $(LIB_CFLAGS) -I..
+LDFLAGS += -L.. -lmultipath
+LIBDEPS = -lmultipath -laio -lpthread -lrt
 
 # If you add or remove a checker also update multipath/multipath.conf.5
 LIBS= \
@@ -17,11 +19,8 @@ LIBS= \
 
 all: $(LIBS)
 
-libcheckdirectio.so: directio.o
-	$(CC) $(LDFLAGS) $(SHARED_FLAGS) -o $@ $^ -laio
-
 libcheck%.so: %.o
-	$(CC) $(LDFLAGS) $(SHARED_FLAGS) -o $@ $^
+	$(CC) $(LDFLAGS) $(SHARED_FLAGS) -o $@ $^ $(LIBDEPS)
 
 install:
 	$(INSTALL_PROGRAM) -m 755 $(LIBS) $(DESTDIR)$(libdir)
diff --git a/libmultipath/foreign/Makefile b/libmultipath/foreign/Makefile
index fae58a0d..f447a1c4 100644
--- a/libmultipath/foreign/Makefile
+++ b/libmultipath/foreign/Makefile
@@ -5,13 +5,15 @@ TOPDIR=../..
 include ../../Makefile.inc
 
 CFLAGS += $(LIB_CFLAGS) -I.. -I$(nvmedir)
+LDFLAGS += -L..
+LIBDEPS = -lmultipath -ludev -lpthread -lrt
 
 LIBS = libforeign-nvme.so
 
 all: $(LIBS)
 
 libforeign-%.so: %.o
-	$(CC) $(LDFLAGS) $(SHARED_FLAGS) -o $@ $^
+	$(CC) $(LDFLAGS) $(SHARED_FLAGS) -o $@ $^ $(LIBDEPS)
 
 install:
 	$(INSTALL_PROGRAM) -m 755 $(LIBS) $(DESTDIR)$(libdir)
diff --git a/libmultipath/prioritizers/Makefile b/libmultipath/prioritizers/Makefile
index fc6e0e0c..8d34ae32 100644
--- a/libmultipath/prioritizers/Makefile
+++ b/libmultipath/prioritizers/Makefile
@@ -4,6 +4,8 @@
 include ../../Makefile.inc
 
 CFLAGS += $(LIB_CFLAGS) -I..
+LDFLAGS += -L..
+LIBDEPS = -lmultipath -lm -lpthread -lrt
 
 # If you add or remove a prioritizer also update multipath/multipath.conf.5
 LIBS = \
@@ -28,11 +30,8 @@ endif
 
 all: $(LIBS)
 
-libpriopath_latency.so: path_latency.o
-	$(CC) $(LDFLAGS) $(SHARED_FLAGS) -o $@ $^ -lm
-
 libprio%.so: %.o
-	$(CC) $(LDFLAGS) $(SHARED_FLAGS) -o $@ $^
+	$(CC) $(LDFLAGS) $(SHARED_FLAGS) -o $@ $^ $(LIBDEPS)
 
 install: $(LIBS)
 	$(INSTALL_PROGRAM) -m 755 libprio*.so $(DESTDIR)$(libdir)
-- 
2.17.2