6949596 wrong section alignment generated in joint compilation with shared library

9 files changed, 105 insertions, 32 deletions

diff --git a/usr/src/cmd/sgs/include/debug.h b/usr/src/cmd/sgs/include/debug.h
index 0e13600956..9544cfec4c 100644
--- a/usr/src/cmd/sgs/include/debug.h
+++ b/usr/src/cmd/sgs/include/debug.h
@@ -458,6 +458,7 @@ extern	void		Dbg_help(void);
 #define	Dbg_syms_cap_local	Dbg64_syms_cap_local
 #define	Dbg_syms_cap_lookup	Dbg64_syms_cap_lookup
 #define	Dbg_syms_cap_title	Dbg64_syms_cap_title
+#define	Dbg_syms_copy_reloc	Dbg64_syms_copy_reloc
 #define	Dbg_syms_created	Dbg64_syms_created
 #define	Dbg_syms_discarded	Dbg64_syms_discarded
 #define	Dbg_syms_dup_discarded	Dbg64_syms_dup_discarded
@@ -473,7 +474,6 @@ extern	void		Dbg_help(void);
 #define	Dbg_syms_old		Dbg64_syms_old
 #define	Dbg_syms_process	Dbg64_syms_process
 #define	Dbg_syms_reduce		Dbg64_syms_reduce
-#define	Dbg_syms_reloc		Dbg64_syms_reloc
 #define	Dbg_syms_resolved	Dbg64_syms_resolved
 #define	Dbg_syms_resolving	Dbg64_syms_resolving
 #define	Dbg_syms_sec_entry	Dbg64_syms_sec_entry
@@ -690,6 +690,7 @@ extern	void		Dbg_help(void);
 #define	Dbg_syms_cap_local	Dbg32_syms_cap_local
 #define	Dbg_syms_cap_lookup	Dbg32_syms_cap_lookup
 #define	Dbg_syms_cap_title	Dbg32_syms_cap_title
+#define	Dbg_syms_copy_reloc	Dbg32_syms_copy_reloc
 #define	Dbg_syms_created	Dbg32_syms_created
 #define	Dbg_syms_discarded	Dbg32_syms_discarded
 #define	Dbg_syms_dup_discarded	Dbg32_syms_dup_discarded
@@ -706,7 +707,6 @@ extern	void		Dbg_help(void);
 #define	Dbg_syms_old		Dbg32_syms_old
 #define	Dbg_syms_process	Dbg32_syms_process
 #define	Dbg_syms_reduce		Dbg32_syms_reduce
-#define	Dbg_syms_reloc		Dbg32_syms_reloc
 #define	Dbg_syms_resolved	Dbg32_syms_resolved
 #define	Dbg_syms_resolving	Dbg32_syms_resolving
 #define	Dbg_syms_sec_entry	Dbg32_syms_sec_entry
@@ -981,6 +981,7 @@ extern	void	Dbg_syms_cap_local(Ofl_desc *, Word, const char *, Sym *,
 extern	void	Dbg_syms_cap_lookup(Rt_map *, uint_t, const char *, uint_t,
 		    Half, Syscapset *);
 extern	void	Dbg_syms_cap_title(Ofl_desc *);
+extern	void	Dbg_syms_copy_reloc(Ofl_desc *, Sym_desc *, Word);
 extern	void	Dbg_syms_created(Lm_list *, const char *);
 extern	void	Dbg_syms_discarded(Lm_list *, Sym_desc *);
 extern	void	Dbg_syms_dup_discarded(Lm_list *, Word ndx, Sym_desc *);
@@ -1001,7 +1002,6 @@ extern	void	Dbg_syms_old(Ofl_desc *, Sym_desc *);
 extern	void	Dbg_syms_process(Lm_list *, Ifl_desc *);
 extern	void	Dbg_syms_reduce(Ofl_desc *, int, Sym_desc *, int,
 		    const char *);
-extern	void	Dbg_syms_reloc(Ofl_desc *, Sym_desc *);
 extern	void	Dbg_syms_resolved(Ofl_desc *, Sym_desc *);
 extern	void	Dbg_syms_resolving(Ofl_desc *, Word, const char *, int, int,
 		    Sym *, Sym *, Sym_desc *, Ifl_desc *);
diff --git a/usr/src/cmd/sgs/ldd/common/ldd.c b/usr/src/cmd/sgs/ldd/common/ldd.c
index 1c9ded6026..27d7ce74f8 100644
--- a/usr/src/cmd/sgs/ldd/common/ldd.c
+++ b/usr/src/cmd/sgs/ldd/common/ldd.c
@@ -29,7 +29,7 @@
  * Print the list of shared objects required by a dynamic executable or shared
  * object.
  *
- * usage is: ldd [-d | -r] [-D] [-c] [-e envar] [-i] [-f] [-L] [-l] [-p] [-s]
+ * usage is: ldd [-d | -r] [-c] [-D] [-e envar] [-i] [-f] [-L] [-l] [-p] [-s]
  *		[-U | -u] [-v] [-w] file(s)
  *
  * ldd opens the file and verifies the information in the elf header.
diff --git a/usr/src/cmd/sgs/libld/common/relocate.c b/usr/src/cmd/sgs/libld/common/relocate.c
index 5c2ca2b711..64cc687204 100644
--- a/usr/src/cmd/sgs/libld/common/relocate.c
+++ b/usr/src/cmd/sgs/libld/common/relocate.c
@@ -1007,6 +1007,22 @@ ld_reloc_plt(Rel_desc *rsp, Ofl_desc *ofl)
 }
 
 /*
+ * Round up to the next power of 2.  Used to ensure section alignments that can
+ * be used for copy relocation symbol alignments are sane values.
+ */
+static Word
+nlpo2(Word val)
+{
+	val--;
+	val |= (val >> 1);
+	val |= (val >> 2);
+	val |= (val >> 4);
+	val |= (val >> 8);
+	val |= (val >> 16);
+	return (++val);
+}
+
+/*
  * process GLOBAL undefined and ref_dyn_need symbols.
  */
 static uintptr_t
@@ -1056,7 +1072,7 @@ reloc_exec(Rel_desc *rsp, Ofl_desc *ofl)
 
 	/*
 	 * If the reference isn't to an object (normally because a .type
-	 * directive hasn't defined in some assembler source), then simply apply
+	 * directive wasn't defined in some assembler source), then apply
 	 * a generic relocation (this has a tendency to result in text
 	 * relocations).
 	 */
@@ -1074,7 +1090,7 @@ reloc_exec(Rel_desc *rsp, Ofl_desc *ofl)
 	/*
 	 * Prepare for generating a copy relocation.
 	 *
-	 * If this symbol is one of an alias pair, we need to insure both
+	 * If this symbol is one of an alias pair, we need to ensure both
 	 * symbols become part of the output (the strong symbol will be used to
 	 * maintain the symbols state).  And, if we did raise the precedence of
 	 * a symbol we need to check and see if this is a weak symbol.  If it is
@@ -1131,10 +1147,16 @@ reloc_exec(Rel_desc *rsp, Ofl_desc *ofl)
 	 * to the executables .bss at runtime.
 	 */
 	if (!(RELAUX_GET_USYM(rsp)->sd_flags & FLG_SY_MVTOCOMM)) {
-		Word		rtype = rsp->rel_rtype;
+		Word		rtype = rsp->rel_rtype, w2align;
 		Copy_rel	cr;
 
 		/*
+		 * Diagnose the original copy reference, as this symbol
+		 * information will be overridden with the new destination.
+		 */
+		DBG_CALL(Dbg_syms_copy_reloc(ofl, sdp, 0));
+
+		/*
 		 * Indicate that the symbol(s) against which we're relocating
 		 * have been moved to the executables common.  Also, insure that
 		 * the symbol(s) remain marked as global, as the shared object
@@ -1171,9 +1193,7 @@ reloc_exec(Rel_desc *rsp, Ofl_desc *ofl)
 		}
 
 		/*
-		 * Assign the symbol to the bss and insure sufficient alignment
-		 * (we don't know the real alignment so we have to make the
-		 * worst case guess).
+		 * Assign the symbol to the bss.
 		 */
 		_sdp = RELAUX_GET_USYM(rsp);
 		stval = _sdp->sd_sym->st_value;
@@ -1181,9 +1201,37 @@ reloc_exec(Rel_desc *rsp, Ofl_desc *ofl)
 			return (S_ERROR);
 		_sdp->sd_shndx = _sdp->sd_sym->st_shndx = SHN_COMMON;
 		_sdp->sd_flags |= FLG_SY_SPECSEC;
-		_sdp->sd_sym->st_value =
-		    (_sdp->sd_sym->st_size < (ld_targ.t_m.m_word_align * 2)) ?
-		    ld_targ.t_m.m_word_align : ld_targ.t_m.m_word_align * 2;
+
+		/*
+		 * Ensure the symbol has sufficient alignment.  The symbol
+		 * definition has no alignment information that can be used,
+		 * hence we use a heuristic.  Historically, twice the native
+		 * word alignment was sufficient for any data type, however,
+		 * the developer may have requested larger alignments (pragma
+		 * align).  The most conservative approach is to use a power
+		 * of two alignment, determined from the alignment of the
+		 * section containing the symbol definition.  Note that this
+		 * can result in some bloat to the .bss as the not every item
+		 * of copied data might need the section alignment.
+		 *
+		 * COMMON symbols carry their alignment requirements in the
+		 * symbols st_value field.  This alignment is applied to the
+		 * symbol when it is eventually transformed into .bss.
+		 */
+		w2align = ld_targ.t_m.m_word_align * 2;
+		if (_sdp->sd_sym->st_size < w2align)
+			_sdp->sd_sym->st_value = ld_targ.t_m.m_word_align;
+		else {
+			Shdr	*shdr;
+			Word	isalign;
+
+			if (_sdp->sd_isc &&
+			    ((shdr = _sdp->sd_isc->is_shdr) != NULL) &&
+			    ((isalign = shdr->sh_addralign) != 0))
+				_sdp->sd_sym->st_value = nlpo2(isalign);
+			else
+				_sdp->sd_sym->st_value = w2align;
+		}
 
 		/*
 		 * Whether or not the symbol references initialized data we
@@ -1213,7 +1261,13 @@ reloc_exec(Rel_desc *rsp, Ofl_desc *ofl)
 		rsp->rel_rtype = rtype;
 
 		/*
-		 * If this symbol is a protected symbol, warn it.
+		 * If this symbol is a protected symbol, warn the user.  A
+		 * potential issue exists as the copy relocated symbol within
+		 * the executable can be visible to others, whereas the shared
+		 * object that defined the original copy data symbol is pre-
+		 * bound to reference it's own definition.  Any modification
+		 * of the symbols data could lead to inconsistencies for the
+		 * various users.
 		 */
 		if (_sdp->sd_flags & FLG_SY_PROT) {
 			Conv_inv_buf_t inv_buf;
@@ -1224,7 +1278,8 @@ reloc_exec(Rel_desc *rsp, Ofl_desc *ofl)
 			    ld_targ.t_m.m_r_copy, 0, &inv_buf),
 			    _sdp->sd_file->ifl_name, _sdp->sd_name);
 		}
-		DBG_CALL(Dbg_syms_reloc(ofl, sdp));
+		DBG_CALL(Dbg_syms_copy_reloc(ofl, _sdp,
+		    _sdp->sd_sym->st_value));
 	}
 	return (ld_add_actrel(NULL, rsp, ofl));
 }
diff --git a/usr/src/cmd/sgs/liblddbg/common/liblddbg.msg b/usr/src/cmd/sgs/liblddbg/common/liblddbg.msg
index b4222142e0..d24d241be1 100644
--- a/usr/src/cmd/sgs/liblddbg/common/liblddbg.msg
+++ b/usr/src/cmd/sgs/liblddbg/common/liblddbg.msg
@@ -975,6 +975,8 @@
 			 (-z symbolcap)"
 @ MSG_SYM_CAP_LOCAL	"symbol[%d]=%s  creating local capability \
 			 (-z symbolcap)"
+@ MSG_SYM_COPY_DST	"symbol=%s;  copy destination: alignment: 0x%x"
+@ MSG_SYM_COPY_REF	"symbol=%s;  copy reference"
 
 @ MSG_SYM_AOUT		"symbol=%s;  (original AOUT name)"
 @ MSG_SYM_LOOKUP	"symbol=%s;  lookup in file=%s  [ %s ]"
@@ -1592,7 +1594,7 @@
 
 @ MSG_SYM_GLOBAL	"global"
 @ MSG_SYM_LOCAL		"local"
-@ MSG_SYM_COPY		"copy rel"
+@ MSG_SYM_COPY		"copy"
 
 @ MSG_DLSYM_NEXT	"[ RTLD_NEXT ]"
 @ MSG_DLSYM_DEFAULT	"[ RTLD_DEFAULT ]"
diff --git a/usr/src/cmd/sgs/liblddbg/common/llib-llddbg b/usr/src/cmd/sgs/liblddbg/common/llib-llddbg
index d642fbc66a..9c090f2571 100644
--- a/usr/src/cmd/sgs/liblddbg/common/llib-llddbg
+++ b/usr/src/cmd/sgs/liblddbg/common/llib-llddbg
@@ -419,6 +419,8 @@ void	Dbg64_syms_cap_lookup(Rt_map *, uint_t, const char *, uint_t, Half,
 	    Syscapset *);
 void	Dbg32_syms_cap_title(Ofl_desc *);
 void	Dbg64_syms_cap_title(Ofl_desc *);
+void	Dbg32_syms_copy_reloc(Ofl_desc *, Sym_desc *, Word);
+void	Dbg64_syms_copy_reloc(Ofl_desc *, Sym_desc *, Word);
 void	Dbg32_syms_created(Lm_list *, const char *);
 void	Dbg64_syms_created(Lm_list *, const char *);
 void	Dbg32_syms_discarded(Lm_list *, Sym_desc *);
@@ -444,8 +446,6 @@ void	Dbg32_syms_process(Lm_list *, Ifl_desc *);
 void	Dbg64_syms_process(Lm_list *, Ifl_desc *);
 void	Dbg32_syms_reduce(Ofl_desc *, int, Sym_desc *, int, const char *);
 void	Dbg64_syms_reduce(Ofl_desc *, int, Sym_desc *, int, const char *);
-void	Dbg32_syms_reloc(Ofl_desc *, Sym_desc *);
-void	Dbg64_syms_reloc(Ofl_desc *, Sym_desc *);
 void	Dbg32_syms_resolved(Ofl_desc *, Sym_desc *);
 void	Dbg64_syms_resolved(Ofl_desc *, Sym_desc *);
 void	Dbg32_syms_resolving(Ofl_desc *, Elf32_Word, const char *, int, int,
diff --git a/usr/src/cmd/sgs/liblddbg/common/mapfile-vers b/usr/src/cmd/sgs/liblddbg/common/mapfile-vers
index 5adf699ee4..ad9fa30e92 100644
--- a/usr/src/cmd/sgs/liblddbg/common/mapfile-vers
+++ b/usr/src/cmd/sgs/liblddbg/common/mapfile-vers
@@ -40,7 +40,7 @@
 # MAPFILE HEADER END
 #
 
-SUNWprivate_4.79 {
+SUNWprivate_4.80 {
 	global:
 		dbg_desc = NODIRECT;	# interposed - ld.so.1(1)
 		dbg_print = NODIRECT;	# interposed - ld(1) and ld.so.1(1)
@@ -398,6 +398,8 @@ SUNWprivate_4.79 {
 		Dbg64_syms_cap_lookup;
 		Dbg32_syms_cap_title;
 		Dbg64_syms_cap_title;
+		Dbg32_syms_copy_reloc;
+		Dbg64_syms_copy_reloc;
 		Dbg32_syms_created;
 		Dbg64_syms_created;
 		Dbg32_syms_discarded;
@@ -429,8 +431,6 @@ SUNWprivate_4.79 {
 		Dbg64_syms_process;
 		Dbg32_syms_reduce;
 		Dbg64_syms_reduce;
-		Dbg32_syms_reloc;
-		Dbg64_syms_reloc;
 		Dbg32_syms_resolved;
 		Dbg64_syms_resolved;
 		Dbg32_syms_resolving;
diff --git a/usr/src/cmd/sgs/liblddbg/common/syms.c b/usr/src/cmd/sgs/liblddbg/common/syms.c
index 3fffd6eb7b..3083eec1fa 100644
--- a/usr/src/cmd/sgs/liblddbg/common/syms.c
+++ b/usr/src/cmd/sgs/liblddbg/common/syms.c
@@ -481,7 +481,7 @@ Dbg_syms_resolved(Ofl_desc *ofl, Sym_desc *sdp)
 }
 
 void
-Dbg_syms_reloc(Ofl_desc *ofl, Sym_desc *sdp)
+Dbg_syms_copy_reloc(Ofl_desc *ofl, Sym_desc *sdp, Word align)
 {
 	static Boolean	symbol_title = TRUE;
 	Conv_inv_buf_t	inv_buf;
@@ -496,8 +496,20 @@ Dbg_syms_reloc(Ofl_desc *ofl, Sym_desc *sdp)
 
 		symbol_title = FALSE;
 	}
-	dbg_print(lml, MSG_INTL(MSG_SYM_UPDATE),
-	    Dbg_demangle_name(sdp->sd_name));
+
+	/*
+	 * Copy relocation symbols come in pairs, the original reference
+	 * (within a dependency), and the new destination (within the .bss of
+	 * the executable).  The latter is accompanied with a computed
+	 * alignment.
+	 */
+	if (align) {
+		dbg_print(lml, MSG_INTL(MSG_SYM_COPY_DST),
+		    Dbg_demangle_name(sdp->sd_name), EC_WORD(align));
+	} else {
+		dbg_print(lml, MSG_INTL(MSG_SYM_COPY_REF),
+		    Dbg_demangle_name(sdp->sd_name));
+	}
 
 	if (DBG_NOTDETAIL())
 		return;
diff --git a/usr/src/cmd/sgs/packages/common/SUNWonld-README b/usr/src/cmd/sgs/packages/common/SUNWonld-README
index c275915fb5..ec62f28dc2 100644
--- a/usr/src/cmd/sgs/packages/common/SUNWonld-README
+++ b/usr/src/cmd/sgs/packages/common/SUNWonld-README
@@ -1295,6 +1295,8 @@ Bugid   Risk Synopsis
 	when mmap fails in anon_map()
 6826513 ldd gets confused by a crle(1) LD_PRELOAD setting
 6684577 ld should propagate SHF_LINK_ORDER flag to ET_REL objects
+6524709 executables using /usr/lib/libc.so.1 as the ELF interpreter dump core
+	(link-editor components only)
 --------------------------------------------------------------------------------
 All the above changes are incorporated in the following patches:
 	Solaris/SunOS 5.10_sparc	patch T143895-01
@@ -1342,8 +1344,6 @@ Bugid   Risk Synopsis
 	PSARC/2007/074 -L option for nm(1) to display SHT_SUNW_LDYNSYM symbols
 6523787 dlopen() handle gets mistakenly orphaned - results in access to freed
 	memory
-6524709 executables using /usr/lib/libc.so.1 as the ELF interpreter dump core
-	(link-editor components only)
 6531189 SEGV in dladdr()
 6527318 dlopen(name, RTLD_NOLOAD) returns handle for unloaded library
 6518359 extern mapfiles references to _init/_fini can create INIT/FINI
@@ -1590,3 +1590,5 @@ Bugid   Risk Synopsis
 6943432 dlsym(RTLD_PROBE) should only bind to symbol definitions
 6668759 an external method for determining whether an ELF dependency is optional
 6954032 Support library with ld_open and -z allextract in snv_139 do not mix
+6949596 wrong section alignment generated in joint compilation with shared
+	library
diff --git a/usr/src/cmd/sgs/rtld/common/dlfcns.c b/usr/src/cmd/sgs/rtld/common/dlfcns.c
index 592d0cb96c..06920e6b59 100644
--- a/usr/src/cmd/sgs/rtld/common/dlfcns.c
+++ b/usr/src/cmd/sgs/rtld/common/dlfcns.c
@@ -1542,12 +1542,14 @@ dladdr_core(Rt_map *almp, void *addr, Dl_info_t *dlip, void **info, int flags)
 int
 dladdr(void *addr, Dl_info_t *dlip)
 {
-	int	entry, error;
+	int	entry, ret;
 	Rt_map	*clmp, *almp;
+	Lm_list	*clml;
 
 	entry = enter(0);
 
 	clmp = _caller(caller(), CL_EXECDEF);
+	clml = LIST(clmp);
 
 	DBG_CALL(Dbg_dl_dladdr(clmp, addr));
 
@@ -1557,17 +1559,17 @@ dladdr(void *addr, Dl_info_t *dlip)
 	 * indicate the failure.
 	 */
 	if ((almp = _caller(addr, CL_NONE)) == NULL) {
-		eprintf(LIST(clmp), ERR_FATAL, MSG_INTL(MSG_ARG_INVADDR),
+		eprintf(clml, ERR_FATAL, MSG_INTL(MSG_ARG_INVADDR),
 		    EC_NATPTR(addr));
-		error = 0;
+		ret = 0;
 	} else {
 		dladdr_core(almp, addr, dlip, 0, 0);
-		error = 1;
+		ret = 1;
 	}
 
 	if (entry)
-		leave(0, 0);
-	return (error);
+		leave(clml, 0);
+	return (ret);
 }
 
 #pragma weak _dladdr1 = dladdr1