Bernd Schmidt writes: abstract away addresses so we can support FDPIC ELFs

9 files changed, 167 insertions, 78 deletions

diff --git a/ldso/include/dl-defs.h b/ldso/include/dl-defs.h
index 878ebc3b8..dc6531d19 100644
--- a/ldso/include/dl-defs.h
+++ b/ldso/include/dl-defs.h
@@ -66,4 +66,70 @@ typedef struct {
 
 #endif
 
+/* Machines in which different sections may be relocated by different
+   amounts should define this and LD_RELOC_ADDR.  If you change this,
+   make sure you change struct link_map in include/link.h accordingly
+   such that it matches a prefix of struct elf_resolve.  */
+#ifndef DL_LOADADDR_TYPE
+# define DL_LOADADDR_TYPE ElfW(Addr)
+#endif
+
+/* When DL_LOADADDR_TYPE is not a scalar value, or some different
+   computation is needed to relocate an address, define this.  */
+#ifndef DL_RELOC_ADDR
+# define DL_RELOC_ADDR(ADDR, LOADADDR) \
+  ((void*)((intptr_t)(ADDR) + (intptr_t)(LOADADDR)))
+#endif
+
+/* Define if any declarations/definitions of local variables are
+   needed in a function that calls DT_INIT_LOADADDR or
+   DL_INIT_LOADADDR_HDR.  Declarations must be properly terminated
+   with a semicolon, and non-declaration statements are forbidden.  */
+#ifndef DL_INIT_LOADADDR_EXTRA_DECLS
+# define DL_INIT_LOADADDR_EXTRA_DECLS /* int i; */
+#endif
+
+/* Prepare a DL_LOADADDR_TYPE data structure for incremental
+   initialization with DL_INIT_LOADADDR_HDR, given pointers to a base
+   load address and to program headers.  */
+#ifndef DL_INIT_LOADADDR
+# define DL_INIT_LOADADDR(LOADADDR, BASEADDR, PHDR, PHDRCNT) \
+  ((LOADADDR) = (BASEADDR))
+#endif
+
+/* Convert a DL_LOADADDR_TYPE to an identifying pointer.  Used mostly
+   for debugging.  */
+#ifndef DL_LOADADDR_BASE
+# define DL_LOADADDR_BASE(LOADADDR) (LOADADDR)
+#endif
+
+/* Initialize a LOADADDR representing the loader itself.  It's only
+   called from DL_BOOT, so additional arguments passed to it may be
+   referenced.  */
+#ifndef DL_INIT_LOADADDR_BOOT
+# define DL_INIT_LOADADDR_BOOT(LOADADDR, BASEADDR) \
+  ((LOADADDR) = (BASEADDR))
+#endif
+
+/* Initialize a LOADADDR representing the program.  It's called from
+   DL_BOOT only.  */
+#ifndef DL_INIT_LOADADDR_PROG
+# define DL_INIT_LOADADDR_PROG(LOADADDR, BASEADDR) \
+  ((LOADADDR) = (BASEADDR))
+#endif
+
+/* Test whether a given ADDR is more likely to be within the memory
+   region mapped to TPNT (a struct elf_resolve *) than to TFROM.
+   Everywhere that this is used, TFROM is initially NULL, and whenever
+   a potential match is found, it's updated.  One might want to walk
+   the chain of elf_resolve to locate the best match and return false
+   whenever TFROM is non-NULL, or use an exact-matching algorithm
+   using additional information encoded in DL_LOADADDR_TYPE to test
+   for exact containment.  */
+#ifndef DL_ADDR_IN_LOADADDR
+# define DL_ADDR_IN_LOADADDR(ADDR, TPNT, TFROM) \
+  ((void*)(TPNT)->loadaddr < (void*)(ADDR)			\
+   && (! (TFROM) || (TFROM)->loadaddr < (TPNT)->loadaddr))
+#endif
+
 #endif	/* _LD_DEFS_H */
diff --git a/ldso/include/dl-elf.h b/ldso/include/dl-elf.h
index de404aec1..9e364d680 100644
--- a/ldso/include/dl-elf.h
+++ b/ldso/include/dl-elf.h
@@ -94,10 +94,12 @@ extern void _dl_protect_relro (struct elf_resolve *l);
 
 #define DYNAMIC_SIZE (DT_NUM+OS_NUM+ARCH_NUM)
 
-extern void _dl_parse_dynamic_info(ElfW(Dyn) *dpnt, unsigned long dynamic_info[], void *debug_addr, ElfW(Addr) load_off);
+extern void _dl_parse_dynamic_info(ElfW(Dyn) *dpnt, unsigned long dynamic_info[], void *debug_addr,
+				   DL_LOADADDR_TYPE load_off);
 
 static __always_inline
-void __dl_parse_dynamic_info(ElfW(Dyn) *dpnt, unsigned long dynamic_info[], void *debug_addr, ElfW(Addr) load_off)
+void __dl_parse_dynamic_info(ElfW(Dyn) *dpnt, unsigned long dynamic_info[], void *debug_addr,
+			     DL_LOADADDR_TYPE load_off)
 {
 	for (; dpnt->d_tag; dpnt++) {
 		if (dpnt->d_tag < DT_NUM) {
@@ -139,7 +141,8 @@ void __dl_parse_dynamic_info(ElfW(Dyn) *dpnt, unsigned long dynamic_info[], void
 #define ADJUST_DYN_INFO(tag, load_off) \
 	do { \
 		if (dynamic_info[tag]) \
-			dynamic_info[tag] += load_off; \
+			dynamic_info[tag] = (unsigned long)DL_RELOC_ADDR (dynamic_info[tag], \
+									  load_off); \
 	} while(0)
 	ADJUST_DYN_INFO(DT_HASH, load_off);
 	ADJUST_DYN_INFO(DT_PLTGOT, load_off);
diff --git a/ldso/include/dl-hash.h b/ldso/include/dl-hash.h
index b12b36f3b..26fb334fe 100644
--- a/ldso/include/dl-hash.h
+++ b/ldso/include/dl-hash.h
@@ -28,7 +28,7 @@ struct dyn_elf{
 struct elf_resolve{
   /* These entries must be in this order to be compatible with the interface used
      by gdb to obtain the list of symbols. */
-  ElfW(Addr) loadaddr;		/* Base address shared object is loaded at.  */
+  DL_LOADADDR_TYPE loadaddr;	/* Base address shared object is loaded at.  */
   char *libname;		/* Absolute file name object was found in.  */
   ElfW(Dyn) *dynamic_addr;	/* Dynamic section of the shared object.  */
   struct elf_resolve * next;
@@ -77,7 +77,7 @@ extern struct elf_resolve * _dl_loaded_modules;
 extern struct dyn_elf 	  * _dl_handles;
 
 extern struct elf_resolve * _dl_add_elf_hash_table(const char * libname, 
-	char * loadaddr, unsigned long * dynamic_info, 
+	DL_LOADADDR_TYPE loadaddr, unsigned long * dynamic_info, 
 	unsigned long dynamic_addr, unsigned long dynamic_size);
 
 extern char * _dl_find_hash(const char * name, struct dyn_elf * rpnt1, 
diff --git a/ldso/include/ldso.h b/ldso/include/ldso.h
index 0a3f70691..573652e61 100644
--- a/ldso/include/ldso.h
+++ b/ldso/include/ldso.h
@@ -88,7 +88,7 @@ extern void _dl_unsetenv(const char *symbol, char **envp);
 extern char *_dl_strdup(const char *string);
 extern void _dl_dprintf(int, const char *, ...);
 
-extern void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
+extern void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
 		ElfW(auxv_t) auxvt[AT_EGID + 1], char **envp, char **argv);
 
 #endif /* _LDSO_H_ */
diff --git a/ldso/ldso/dl-elf.c b/ldso/ldso/dl-elf.c
index d0ea4dac7..f98d76b88 100644
--- a/ldso/ldso/dl-elf.c
+++ b/ldso/ldso/dl-elf.c
@@ -118,10 +118,10 @@ int _dl_unmap_cache(void)
 void
 _dl_protect_relro (struct elf_resolve *l)
 {
-	ElfW(Addr) start = ((l->loadaddr + l->relro_addr)
-			    & ~(_dl_pagesize - 1));
-	ElfW(Addr) end = ((l->loadaddr + l->relro_addr + l->relro_size)
-			  & ~(_dl_pagesize - 1));
+	ElfW(Addr) base = (ElfW(Addr)) DL_RELOC_ADDR (l->relro_addr,
+						      l->loadaddr);
+	ElfW(Addr) start = (base & ~(_dl_pagesize - 1));
+	ElfW(Addr) end = ((base + l->relro_size) & ~(_dl_pagesize - 1));
 	_dl_if_debug_dprint("RELRO protecting %s:  start:%x, end:%x\n", l->libname, start, end);
 	if (start != end &&
 	    _dl_mprotect ((void *) start, end - start, PROT_READ) < 0) {
@@ -262,7 +262,8 @@ struct elf_resolve *_dl_load_shared_library(int secure, struct dyn_elf **rpnt,
 #ifdef __LDSO_RUNPATH__
 	pnt = (tpnt ? (char *)tpnt->dynamic_info[DT_RUNPATH] : NULL);
 	if (pnt) {
-		pnt += (unsigned long) tpnt->dynamic_info[DT_STRTAB];
+		pnt += (intptr_t) DL_RELOC_ADDR (tpnt->dynamic_info[DT_STRTAB],
+						 tpnt->loadaddr);
 		_dl_if_debug_dprint("\tsearching RUNPATH='%s'\n", pnt);
 		if ((tpnt1 = search_for_named_library(libname, secure, pnt, rpnt)) != NULL)
 			return tpnt1;
@@ -352,6 +353,8 @@ struct elf_resolve *_dl_load_elf_shared_library(int secure,
 	ElfW(Addr) relro_addr = 0;
 	size_t relro_size = 0;
 	struct stat st;
+	DL_LOADADDR_TYPE lib_loadaddr;
+	DL_INIT_LOADADDR_EXTRA_DECLS
 
 	libaddr = 0;
 	infile = _dl_open(libname, O_RDONLY, 0);
@@ -467,7 +470,10 @@ struct elf_resolve *_dl_load_elf_shared_library(int secure,
 	}
 	libaddr = (unsigned long) status;
 	flags |= MAP_FIXED;
-
+	DL_INIT_LOADADDR (lib_loadaddr, libaddr,
+			  (Elf32_Phdr *)& header[epnt->e_phoff],
+			  epnt->e_phnum);
+	
 	/* Get the memory to store the library */
 	ppnt = (ElfW(Phdr) *)(intptr_t) & header[epnt->e_phoff];
 
@@ -547,7 +553,8 @@ struct elf_resolve *_dl_load_elf_shared_library(int secure,
 
 	/* For a non-PIC library, the addresses are all absolute */
 	if (piclib) {
-		dynamic_addr += (unsigned long) libaddr;
+		dynamic_addr = (unsigned long) DL_RELOC_ADDR (dynamic_addr,
+							      lib_loadaddr);
 	}
 
 	/*
@@ -567,7 +574,7 @@ struct elf_resolve *_dl_load_elf_shared_library(int secure,
 
 	dpnt = (ElfW(Dyn) *) dynamic_addr;
 	_dl_memset(dynamic_info, 0, sizeof(dynamic_info));
-	_dl_parse_dynamic_info(dpnt, dynamic_info, NULL, libaddr);
+	_dl_parse_dynamic_info(dpnt, dynamic_info, NULL, lib_loadaddr);
 	/* If the TEXTREL is set, this means that we need to make the pages
 	   writable before we perform relocations.  Do this now. They get set
 	   back again later. */
@@ -588,13 +595,14 @@ struct elf_resolve *_dl_load_elf_shared_library(int secure,
 #endif
 	}
 
-	tpnt = _dl_add_elf_hash_table(libname, (char *) libaddr, dynamic_info,
+	tpnt = _dl_add_elf_hash_table(libname, lib_loadaddr, dynamic_info,
 			dynamic_addr, 0);
 	tpnt->relro_addr = relro_addr;
 	tpnt->relro_size = relro_size;
 	tpnt->st_dev = st.st_dev;
 	tpnt->st_ino = st.st_ino;
-	tpnt->ppnt = (ElfW(Phdr) *)(intptr_t) (tpnt->loadaddr + epnt->e_phoff);
+	tpnt->ppnt = (ElfW(Phdr) *) DL_RELOC_ADDR (epnt->e_phoff,
+						   tpnt->loadaddr);
 	tpnt->n_phent = epnt->e_phnum;
 
 	/*
@@ -625,9 +633,11 @@ struct elf_resolve *_dl_load_elf_shared_library(int secure,
 	}
 
 	_dl_if_debug_dprint("\n\tfile='%s';  generating link map\n", libname);
-	_dl_if_debug_dprint("\t\tdynamic: %x  base: %x\n", dynamic_addr, libaddr);
+	_dl_if_debug_dprint("\t\tdynamic: %x  base: %x\n", dynamic_addr,
+			    DL_LOADADDR_BASE (libaddr));
 	_dl_if_debug_dprint("\t\t  entry: %x  phdr: %x  phnum: %x\n\n",
-			epnt->e_entry + libaddr, tpnt->ppnt, tpnt->n_phent);
+			    DL_RELOC_ADDR (epnt->e_entry, lib_loadaddr),
+			    tpnt->ppnt, tpnt->n_phent);
 
 	_dl_munmap(header, _dl_pagesize);
 
@@ -801,7 +811,7 @@ char *_dl_strdup(const char *string)
 	return retval;
 }
 
-void _dl_parse_dynamic_info(ElfW(Dyn) *dpnt, unsigned long dynamic_info[], void *debug_addr, ElfW(Addr) load_off)
+void _dl_parse_dynamic_info(ElfW(Dyn) *dpnt, unsigned long dynamic_info[], void *debug_addr, DL_LOADADDR_TYPE load_off)
 {
 	__dl_parse_dynamic_info(dpnt, dynamic_info, debug_addr, load_off);
 }
@@ -818,7 +828,7 @@ __dl_iterate_phdr (int (*callback) (struct dl_phdr_info *info, size_t size, void
 	int ret = 0;
 
 	for (l = _dl_loaded_modules; l != NULL; l = l->next) {
-		info.dlpi_addr = l->loadaddr;
+		info.dlpi_addr = (ElfW(Addr))DL_LOADADDR_BASE (l->loadaddr);
 		info.dlpi_name = l->libname;
 		info.dlpi_phdr = l->ppnt;
 		info.dlpi_phnum = l->n_phent;
diff --git a/ldso/ldso/dl-hash.c b/ldso/ldso/dl-hash.c
index ed55031ed..85b2b403f 100644
--- a/ldso/ldso/dl-hash.c
+++ b/ldso/ldso/dl-hash.c
@@ -83,7 +83,7 @@ static inline Elf_Symndx _dl_elf_hash(const char *name)
  * externals properly.
  */
 struct elf_resolve *_dl_add_elf_hash_table(const char *libname,
-	char *loadaddr, unsigned long *dynamic_info, unsigned long dynamic_addr,
+	DL_LOADADDR_TYPE loadaddr, unsigned long *dynamic_info, unsigned long dynamic_addr,
 	attribute_unused unsigned long dynamic_size)
 {
 	Elf_Symndx *hash_addr;
@@ -117,7 +117,7 @@ struct elf_resolve *_dl_add_elf_hash_table(const char *libname,
 		hash_addr += tpnt->nbucket;
 		tpnt->chains = hash_addr;
 	}
-	tpnt->loadaddr = (ElfW(Addr))loadaddr;
+	tpnt->loadaddr = loadaddr;
 	for (i = 0; i < DYNAMIC_SIZE; i++)
 		tpnt->dynamic_info[i] = dynamic_info[i];
 	return tpnt;
@@ -163,8 +163,10 @@ char *_dl_find_hash(const char *name, struct dyn_elf *rpnt, struct elf_resolve *
 
 		/* Avoid calling .urem here. */
 		do_rem(hn, elf_hash_number, tpnt->nbucket);
-		symtab = (ElfW(Sym) *) (intptr_t) (tpnt->dynamic_info[DT_SYMTAB]);
-		strtab = (char *) (tpnt->dynamic_info[DT_STRTAB]);
+		symtab = (ElfW(Sym) *) DL_RELOC_ADDR (tpnt->dynamic_info[DT_SYMTAB],
+						      tpnt->loadaddr);
+		strtab = (char *) DL_RELOC_ADDR (tpnt->dynamic_info[DT_STRTAB],
+						 tpnt->loadaddr);
 
 		for (si = tpnt->elf_buckets[hn]; si != STN_UNDEF; si = tpnt->chains[si]) {
 			sym = &symtab[si];
@@ -184,11 +186,13 @@ char *_dl_find_hash(const char *name, struct dyn_elf *rpnt, struct elf_resolve *
 /* Perhaps we should support old style weak symbol handling
  * per what glibc does when you export LD_DYNAMIC_WEAK */
 				if (!weak_result)
-					weak_result = (char *)tpnt->loadaddr + sym->st_value;
+					weak_result = (char *) DL_RELOC_ADDR (sym->st_value,
+									      tpnt->loadaddr);
 				break;
 #endif
 			case STB_GLOBAL:
-				return (char*)tpnt->loadaddr + sym->st_value;
+				return (char*) DL_RELOC_ADDR (sym->st_value,
+							      tpnt->loadaddr);
 			default:	/* Local symbols not handled here */
 				break;
 			}
diff --git a/ldso/ldso/dl-startup.c b/ldso/ldso/dl-startup.c
index 96a736448..908ba7cb3 100644
--- a/ldso/ldso/dl-startup.c
+++ b/ldso/ldso/dl-startup.c
@@ -114,7 +114,7 @@ static void * __attribute_used__ _dl_start(unsigned long args)
 {
 	unsigned int argc;
 	char **argv, **envp;
-	unsigned long load_addr;
+	DL_LOADADDR_TYPE load_addr;
 	ElfW(Addr) got;
 	unsigned long *aux_dat;
 	ElfW(Ehdr) *header;
@@ -168,7 +168,7 @@ static void * __attribute_used__ _dl_start(unsigned long args)
 	 * (esp since SEND_STDERR() needs this on some platforms... */
 	if (!auxvt[AT_BASE].a_un.a_val)
 		auxvt[AT_BASE].a_un.a_val = elf_machine_load_address();
-	load_addr = auxvt[AT_BASE].a_un.a_val;
+	DL_INIT_LOADADDR_BOOT(load_addr, auxvt[AT_BASE].a_un.a_val);
 	header = (ElfW(Ehdr) *) auxvt[AT_BASE].a_un.a_val;
 
 	/* Check the ELF header to make sure everything looks ok.  */
@@ -186,14 +186,14 @@ static void * __attribute_used__ _dl_start(unsigned long args)
 		_dl_exit(0);
 	}
 	SEND_STDERR_DEBUG("ELF header=");
-	SEND_ADDRESS_STDERR_DEBUG(load_addr, 1);
+	SEND_ADDRESS_STDERR_DEBUG(DL_LOADADDR_BASE (load_addr), 1);
 
 	/* Locate the global offset table.  Since this code must be PIC
 	 * we can take advantage of the magic offset register, if we
 	 * happen to know what that is for this architecture.  If not,
 	 * we can always read stuff out of the ELF file to find it... */
 	got = elf_machine_dynamic();
-	dpnt = (ElfW(Dyn) *) (got + load_addr);
+	dpnt = (ElfW(Dyn) *) DL_RELOC_ADDR (got, load_addr);
 	SEND_STDERR_DEBUG("First Dynamic section entry=");
 	SEND_ADDRESS_STDERR_DEBUG(dpnt, 1);
 	_dl_memset(tpnt, 0, sizeof(struct elf_resolve));
@@ -259,9 +259,10 @@ static void * __attribute_used__ _dl_start(unsigned long args)
 				rel_addr += relative_count * sizeof(ELF_RELOC);
 			}
 
-			rpnt = (ELF_RELOC *) (rel_addr + load_addr);
+			rpnt = (ELF_RELOC *) DL_RELOC_ADDR (rel_addr, load_addr);
 			for (i = 0; i < rel_size; i += sizeof(ELF_RELOC), rpnt++) {
-				reloc_addr = (unsigned long *) (load_addr + (unsigned long) rpnt->r_offset);
+				reloc_addr = (unsigned long *) DL_RELOC_ADDR ((unsigned long) rpnt->r_offset,
+									      load_addr);
 				symtab_index = ELF_R_SYM(rpnt->r_info);
 				symbol_addr = 0;
 				sym = NULL;
@@ -272,7 +273,7 @@ static void * __attribute_used__ _dl_start(unsigned long args)
 					symtab = (ElfW(Sym) *) tpnt->dynamic_info[DT_SYMTAB];
 					strtab = (char *) tpnt->dynamic_info[DT_STRTAB];
 					sym = &symtab[symtab_index];
-					symbol_addr = load_addr + sym->st_value;
+					symbol_addr = (unsigned long) DL_RELOC_ADDR (sym->st_value, load_addr);
 
 					SEND_STDERR_DEBUG("relocating symbol: ");
 					SEND_STDERR_DEBUG(strtab + sym->st_name);
diff --git a/ldso/ldso/ldso.c b/ldso/ldso/ldso.c
index 2234623e3..2afd97797 100644
--- a/ldso/ldso/ldso.c
+++ b/ldso/ldso/ldso.c
@@ -102,17 +102,18 @@ uintptr_t __guard attribute_relro;
 #endif
 
 static void _dl_run_array_forward(unsigned long array, unsigned long size,
-				  ElfW(Addr) loadaddr)
+				  DL_LOADADDR_TYPE loadaddr)
 {
 	if (array != 0) {
 		unsigned int j;
 		unsigned int jm;
 		ElfW(Addr) *addrs;
 		jm = size / sizeof (ElfW(Addr));
-		addrs = (ElfW(Addr) *) (array + loadaddr);
+		addrs = (ElfW(Addr) *) DL_RELOC_ADDR (array, loadaddr);
 		for (j = 0; j < jm; ++j) {
 			void (*dl_elf_func) (void);
-			dl_elf_func = (void (*)(void)) (intptr_t) addrs[j];
+			dl_elf_func = (void (*)(void)) DL_RELOC_ADDR (addrs[j],
+								      loadaddr);
 			(*dl_elf_func) ();
 		}
 	}
@@ -136,11 +137,13 @@ void _dl_run_fini_array(struct elf_resolve *tpnt);
 void _dl_run_fini_array(struct elf_resolve *tpnt)
 {
 	if (tpnt->dynamic_info[DT_FINI_ARRAY]) {
-		ElfW(Addr) *array = (ElfW(Addr) *) (tpnt->loadaddr + tpnt->dynamic_info[DT_FINI_ARRAY]);
+		ElfW(Addr) *array = (ElfW(Addr) *) DL_RELOC_ADDR (tpnt->dynamic_info[DT_FINI_ARRAY],
+								  tpnt->loadaddr);
 		unsigned int i = (tpnt->dynamic_info[DT_FINI_ARRAYSZ] / sizeof(ElfW(Addr)));
 		while (i-- > 0) {
 			void (*dl_elf_func) (void);
-			dl_elf_func = (void (*)(void)) (intptr_t) array[i];
+			dl_elf_func = (void (*)(void)) DL_RELOC_ADDR (array[i],
+								      tpnt->loadaddr);
 			(*dl_elf_func) ();
 		}
 	}
@@ -166,14 +169,15 @@ static void __attribute__ ((destructor)) __attribute_used__ _dl_fini(void)
 		if (tpnt->dynamic_info[DT_FINI]) {
 			void (*dl_elf_func) (void);
 
-			dl_elf_func = (void (*)(void)) (intptr_t) (tpnt->loadaddr + tpnt->dynamic_info[DT_FINI]);
+			dl_elf_func = (void (*)(void)) DL_RELOC_ADDR (tpnt->dynamic_info[DT_FINI],
+								      tpnt->loadaddr);
 			_dl_if_debug_dprint("\ncalling FINI: %s\n\n", tpnt->libname);
 			(*dl_elf_func) ();
 		}
 	}
 }
 
-void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
+void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
 			  ElfW(auxv_t) auxvt[AT_EGID + 1], char **envp,
 			  char **argv)
 {
@@ -295,13 +299,13 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
 
 		for (idx = 0; idx < auxvt[AT_PHNUM].a_un.a_val; idx++, phdr++)
 			if (phdr->p_type == PT_PHDR) {
-				app_tpnt->loadaddr = (ElfW(Addr)) (auxvt[AT_PHDR].a_un.a_val - phdr->p_vaddr);
+				DL_INIT_LOADADDR_PROG (app_tpnt->loadaddr, (ElfW(Addr)) (auxvt[AT_PHDR].a_un.a_val - ppnt->p_vaddr));
 				break;
 			}
 
-		if (app_tpnt->loadaddr)
+		if (DL_LOADADDR_BASE (app_tpnt->loadaddr))
 			_dl_debug_early("Position Independent Executable: "
-					"app_tpnt->loadaddr=%x\n", app_tpnt->loadaddr);
+					"app_tpnt->loadaddr=%x\n", DL_LOADADDR_BASE (app_tpnt->loadaddr));
 	}
 
 	/*
@@ -318,7 +322,7 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
 			relro_size = ppnt->p_memsz;
 		}
 		if (ppnt->p_type == PT_DYNAMIC) {
-			dpnt = (ElfW(Dyn) *) (ppnt->p_vaddr + app_tpnt->loadaddr);
+			dpnt = (ElfW(Dyn) *) DL_RELOC_ADDR (ppnt->p_vaddr, app_tpnt->loadaddr);
 			_dl_parse_dynamic_info(dpnt, app_tpnt->dynamic_info, debug_addr, app_tpnt->loadaddr);
 #ifndef __FORCE_SHAREABLE_TEXT_SEGMENTS__
 			/* Ugly, ugly.  We need to call mprotect to change the
@@ -331,11 +335,11 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
 			if (app_tpnt->dynamic_info[DT_TEXTREL]) {
 				ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val;
 				for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++) {
-					if (ppnt->p_type == PT_LOAD && !(ppnt->p_flags & PF_W))
-						_dl_mprotect((void *) ((ppnt->p_vaddr + app_tpnt->loadaddr) & PAGE_ALIGN),
-							     ((ppnt->p_vaddr + app_tpnt->loadaddr) & ADDR_ALIGN) +
-							     (unsigned long) ppnt->p_filesz,
+					if (ppnt->p_type == PT_LOAD && !(ppnt->p_flags & PF_W)) {
+						void *base =  DL_RELOC_ADDR (ppnt->p_vaddr & PAGE_ALIGN, app_tpnt->loadaddr);
+						_dl_mprotect(base, (ppnt->p_vaddr & ADDR_ALIGN) + (unsigned long) ppnt->p_filesz,
 							     PROT_READ | PROT_WRITE | PROT_EXEC);
+					}
 				}
 			}
 #endif
@@ -346,8 +350,10 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
 				continue;
 #endif
 			/* OK, we have what we need - slip this one into the list. */
-			app_tpnt = _dl_add_elf_hash_table(_dl_progname, (char *)app_tpnt->loadaddr,
-					app_tpnt->dynamic_info, ppnt->p_vaddr + app_tpnt->loadaddr, ppnt->p_filesz);
+			app_tpnt = _dl_add_elf_hash_table(_dl_progname, app_tpnt->loadaddr,
+							  app_tpnt->dynamic_info,
+							  (unsigned long) DL_RELOC_ADDR (ppnt->p_vaddr, app_tpnt->loadaddr),
+							  ppnt->p_filesz);
 			_dl_loaded_modules->libtype = elf_executable;
 			_dl_loaded_modules->ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val;
 			_dl_loaded_modules->n_phent = auxvt[AT_PHNUM].a_un.a_val;
@@ -368,7 +374,7 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
 		if (ppnt->p_type == PT_INTERP) {
 			char *ptmp;
 
-			tpnt->libname = (char *) ppnt->p_vaddr + app_tpnt->loadaddr;
+			tpnt->libname = (char *) DL_RELOC_ADDR (ppnt->p_vaddr, app_tpnt->loadaddr);
 
 			/* Store the path where the shared lib loader was found
 			 * for later use
@@ -378,7 +384,8 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
 			if (ptmp != _dl_ldsopath)
 				*ptmp = '\0';
 
-			_dl_debug_early("Lib Loader: (%x) %s\n", tpnt->loadaddr, tpnt->libname);
+			_dl_debug_early("Lib Loader: (%x) %s\n", (unsigned) DL_LOADADDR_BASE (tpnt->loadaddr),
+					tpnt->libname);
 		}
 	}
 	app_tpnt->relro_addr = relro_addr;
@@ -450,7 +457,7 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
 	 */
 	debug_addr->r_map = (struct link_map *) _dl_loaded_modules;
 	debug_addr->r_version = 1;
-	debug_addr->r_ldbase = load_addr;
+	debug_addr->r_ldbase = (ElfW(Addr)) DL_LOADADDR_BASE (load_addr);
 	debug_addr->r_brk = (unsigned long) &_dl_debug_state;
 	_dl_debug_addr = debug_addr;
 
@@ -497,7 +504,7 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
 				} else {
 					tpnt1->rtld_flags = unlazy | RTLD_GLOBAL;
 
-					_dl_debug_early("Loading: (%x) %s\n", tpnt1->loadaddr, tpnt1->libname);
+					_dl_debug_early("Loading: (%x) %s\n", (unsigned) DL_LOADADDR_BASE (tpnt1->loadaddr), tpnt1->libname);
 
 #ifdef __LDSO_LDD_SUPPORT__
 					if (trace_loaded_objects &&
@@ -509,7 +516,7 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
 						 */
 						if (_dl_strcmp(_dl_progname, str) != 0)
 							_dl_dprintf(1, "\t%s => %s (%x)\n", str, tpnt1->libname,
-								    tpnt1->loadaddr);
+								    (unsigned) DL_LOADADDR_BASE (tpnt1->loadaddr));
 					}
 #endif
 				}
@@ -588,14 +595,14 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
 			} else {
 				tpnt1->rtld_flags = unlazy | RTLD_GLOBAL;
 
-				_dl_debug_early("Loading: (%x) %s\n", tpnt1->loadaddr, tpnt1->libname);
+				_dl_debug_early("Loading: (%x) %s\n", (unsigned) DL_LOADADDR_BASE (tpnt1->loadaddr), tpnt1->libname);
 
 #ifdef __LDSO_LDD_SUPPORT__
 				if (trace_loaded_objects &&
 				    tpnt1->usage_count == 1) {
 					_dl_dprintf(1, "\t%s => %s (%x)\n",
 						    cp2, tpnt1->libname,
-						    (unsigned)tpnt1->loadaddr);
+						    (unsigned) DL_LOADADDR_BASE (tpnt1->loadaddr));
 				}
 #endif
 			}
@@ -647,14 +654,14 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
 
 				tpnt1->rtld_flags = unlazy | RTLD_GLOBAL;
 
-				_dl_debug_early("Loading: (%x) %s\n", tpnt1->loadaddr, tpnt1->libname);
+				_dl_debug_early("Loading: (%x) %s\n", (unsigned) DL_LOADADDR_BASE (tpnt1->loadaddr), tpnt1->libname);
 
 #ifdef __LDSO_LDD_SUPPORT__
 				if (trace_loaded_objects &&
 				    tpnt1->usage_count == 1) {
 					_dl_dprintf(1, "\t%s => %s (%x)\n",
 						    lpntstr, tpnt1->libname,
-						    (unsigned)tpnt1->loadaddr);
+						    (unsigned) DL_LOADADDR_BASE (tpnt1->loadaddr));
 				}
 #endif
 			}
@@ -715,10 +722,10 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
 	 */
 	if (tpnt) {
 		ElfW(Ehdr) *epnt = (ElfW(Ehdr) *) auxvt[AT_BASE].a_un.a_val;
-		ElfW(Phdr) *myppnt = (ElfW(Phdr) *) (load_addr + epnt->e_phoff);
+		ElfW(Phdr) *myppnt = (ElfW(Phdr) *) DL_RELOC_ADDR (epnt->e_phoff, load_addr);
 		int j;
 
-		tpnt = _dl_add_elf_hash_table(tpnt->libname, (char *)load_addr,
+		tpnt = _dl_add_elf_hash_table(tpnt->libname, load_addr,
 					      tpnt->dynamic_info,
 					      (unsigned long)tpnt->dynamic_addr,
 					      0);
@@ -765,7 +772,7 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
 	if (trace_loaded_objects) {
 		_dl_dprintf(1, "\t%s => %s (%x)\n",
 			    rpnt->dyn->libname + _dl_strlen(_dl_ldsopath) + 1,
-			    rpnt->dyn->libname, rpnt->dyn->loadaddr);
+			    rpnt->dyn->libname, (unsigned) DL_LOADADDR_BASE (rpnt->dyn->loadaddr));
 		_dl_exit(0);
 	}
 #endif
@@ -817,8 +824,10 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
 		for (tpnt = _dl_loaded_modules; tpnt; tpnt = tpnt->next) {
 			for (myppnt = tpnt->ppnt, j = 0; j < tpnt->n_phent; j++, myppnt++) {
 				if (myppnt->p_type == PT_LOAD && !(myppnt->p_flags & PF_W) && tpnt->dynamic_info[DT_TEXTREL]) {
-					_dl_mprotect((void *) (tpnt->loadaddr + (myppnt->p_vaddr & PAGE_ALIGN)),
-							(myppnt->p_vaddr & ADDR_ALIGN) + (unsigned long) myppnt->p_filesz, LXFLAGS(myppnt->p_flags));
+					void *base = DL_RELOC_ADDR (myppnt->p_vaddr & PAGE_ALIGN, tpnt->loadaddr);
+					_dl_mprotect(base,
+						     (myppnt->p_vaddr & ADDR_ALIGN) + (unsigned long) myppnt->p_filesz,
+						     LXFLAGS(myppnt->p_flags));
 				}
 			}
 		}
@@ -846,7 +855,7 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
 		if (tpnt->dynamic_info[DT_INIT]) {
 			void (*dl_elf_func) (void);
 
-			dl_elf_func = (void (*)(void)) (intptr_t) (tpnt->loadaddr + tpnt->dynamic_info[DT_INIT]);
+			dl_elf_func = (void (*)(void)) DL_RELOC_ADDR (tpnt->dynamic_info[DT_INIT], tpnt->loadaddr);
 
 			_dl_if_debug_dprint("calling INIT: %s\n\n", tpnt->libname);
 
diff --git a/ldso/libdl/libdl.c b/ldso/libdl/libdl.c
index 322230860..b533a2da1 100644
--- a/ldso/libdl/libdl.c
+++ b/ldso/libdl/libdl.c
@@ -175,8 +175,7 @@ void *dlopen(const char *libname, int flag)
 		tfrom = NULL;
 		for (dpnt = _dl_symbol_tables; dpnt; dpnt = dpnt->next) {
 			tpnt = dpnt->dyn;
-			if (tpnt->loadaddr < from
-					&& (tfrom == NULL || tfrom->loadaddr < tpnt->loadaddr))
+			if (DL_ADDR_IN_LOADADDR (from, tpnt, tfrom))
 				tfrom = tpnt;
 		}
 	}
@@ -378,7 +377,7 @@ void *dlopen(const char *libname, int flag)
 
 		if (tpnt->dynamic_info[DT_INIT]) {
 			void (*dl_elf_func) (void);
-			dl_elf_func = (void (*)(void)) (tpnt->loadaddr + tpnt->dynamic_info[DT_INIT]);
+			dl_elf_func = (void (*)(void)) DL_RELOC_ADDR (tpnt->dynamic_info[DT_INIT], tpnt->loadaddr);
 			if (dl_elf_func && *dl_elf_func != NULL) {
 				_dl_if_debug_print("running ctors for library %s at '%p'\n",
 						tpnt->libname, dl_elf_func);
@@ -436,8 +435,7 @@ void *dlsym(void *vhandle, const char *name)
 		tfrom = NULL;
 		for (rpnt = _dl_symbol_tables; rpnt; rpnt = rpnt->next) {
 			tpnt = rpnt->dyn;
-			if (tpnt->loadaddr < from
-					&& (tfrom == NULL || tfrom->loadaddr < tpnt->loadaddr)) {
+			if (DL_ADDR_IN_LOADADDR (from, tpnt, tfrom)) {
 				tfrom = tpnt;
 				handle = rpnt->next;
 			}
@@ -512,7 +510,7 @@ static int do_dlclose(void *vhandle, int need_fini)
 #endif
 
 				if (tpnt->dynamic_info[DT_FINI]) {
-					dl_elf_fini = (int (*)(void)) (tpnt->loadaddr + tpnt->dynamic_info[DT_FINI]);
+				    dl_elf_fini = (int (*)(void)) DL_RELOC_ADDR (tpnt->dynamic_info[DT_FINI], tpnt->loadaddr);
 					_dl_if_debug_print("running dtors for library %s at '%p'\n",
 							tpnt->libname, dl_elf_fini);
 					(*dl_elf_fini) ();
@@ -622,7 +620,7 @@ int dlinfo(void)
 	/* First start with a complete list of all of the loaded files. */
 	for (tpnt = _dl_loaded_modules; tpnt; tpnt = tpnt->next) {
 		fprintf(stderr, "\t%p %p %p %s %d %s\n",
-		        tpnt->loadaddr, tpnt, tpnt->symbol_scope,
+		        DL_LOADADDR_BASE (tpnt->loadaddr), tpnt, tpnt->symbol_scope,
 		        type[tpnt->libtype],
 		        tpnt->usage_count, tpnt->libname);
 	}
@@ -662,12 +660,10 @@ int dladdr(const void *__address, Dl_info * __info)
 		tpnt = rpnt;
 #if 0
 		fprintf(stderr, "Module \"%s\" at %p\n",
-				tpnt->libname, tpnt->loadaddr);
+			tpnt->libname, DL_LOADADDR_BASE (tpnt->loadaddr));
 #endif
-		if (tpnt->loadaddr < (ElfW(Addr)) __address
-				&& (pelf == NULL || pelf->loadaddr < tpnt->loadaddr)) {
+		if (DL_ADDR_IN_LOADADDR ((ElfW(Addr)) __address,  tpnt, pelf))
 			pelf = tpnt;
-		}
 	}
 
 	if (!pelf) {
@@ -693,7 +689,7 @@ int dladdr(const void *__address, Dl_info * __info)
 			for (si = pelf->elf_buckets[hn]; si; si = pelf->chains[si]) {
 				ElfW(Addr) symbol_addr;
 
-				symbol_addr = pelf->loadaddr + symtab[si].st_value;
+				symbol_addr = (ElfW(Addr)) DL_RELOC_ADDR (symtab[si].st_value, pelf->loadaddr);
 				if (symbol_addr <= (ElfW(Addr))__address && (!sf || sa < symbol_addr)) {
 					sa = symbol_addr;
 					sn = si;
@@ -708,7 +704,7 @@ int dladdr(const void *__address, Dl_info * __info)
 
 		if (sf) {
 			__info->dli_fname = pelf->libname;
-			__info->dli_fbase = (void *)pelf->loadaddr;
+			__info->dli_fbase = DL_LOADADDR_BASE (pelf->loadaddr);
 			__info->dli_sname = strtab + symtab[sn].st_name;
 			__info->dli_saddr = (void *)sa;
 		}