elf: Check for corrupt symbol version info

The BFD linker with PR ld/23499 may generate shared libraries with
corrupt symbol version info which leads to linker error when the
corrupt shared library is used:

/usr/bin/ld: bin/libKF5Service.so.5.49.0: _edata: invalid version 21 (max 0)
/usr/bin/ld: bin/libKF5Service.so.5.49.0: error adding symbols: bad value

Add check for corrupt symbol version info to objdump:

00000000000af005 g    D  .data	0000000000000000  <corrupt>   _edata

and readelf:

   728: 00000000000af005     0 NOTYPE  GLOBAL DEFAULT   25 _edata@<corrupt> (5)

bfd/

	PR ld/23499
	* elf.c (_bfd_elf_get_symbol_version_string): Return
	_("<corrupt>") for corrupt symbol version info.

binutils/

	PR ld/23499
	* readelf.c (get_symbol_version_string): Return _("<corrupt>")
	for corrupt symbol version info.

2 files changed, 7 insertions, 1 deletions

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index c9e7e2a..3af19d5 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,9 @@
+2018-08-25  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR ld/23499
+	* elf.c (_bfd_elf_get_symbol_version_string): Return
+	_("<corrupt>") for corrupt symbol version info.
+
 2018-08-24  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* elfxx-x86.c (_bfd_x86_elf_parse_gnu_properties): Handle
diff --git a/bfd/elf.c b/bfd/elf.c
index efdaf2e..b8860c4 100644
--- a/bfd/elf.c
+++ b/bfd/elf.c
@@ -1877,7 +1877,7 @@ _bfd_elf_get_symbol_version_string (bfd *abfd, asymbol *symbol,
 	{
 	  Elf_Internal_Verneed *t;
 
-	  version_string = "";
+	  version_string = _("<corrupt>");
 	  for (t = elf_tdata (abfd)->verref;
 	       t != NULL;
 	       t = t->vn_nextref)