script/relocate_sdk.py: check dynamic loader arch before relocating interpreter

While multiple dynamic loader existed, in order to make executable file is
interpreted by the expected dynamic loader, relocating interpreter only if
the new dynamic loader and executable file have the same arch

[ YOCTO #15722 ]

(From OE-Core rev: 0c1f2bf3d8e31e66d28aaa81a7c1658f160bb79e)

Signed-off-by: Hongxu Jia <hongxu.jia@windriver.com>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

scripts/relocate_sdk.py

@@ -49,6 +49,34 @@ def get_arch():
     elif ei_class == 2:
         return 64
 
+def get_dl_arch(dl_path):
+    try:
+        with open(dl_path, "r+b") as f:
+            e_ident =f.read(16)
+    except IOError:
+        exctype, ioex = sys.exc_info()[:2]
+        if ioex.errno == errno.ETXTBSY:
+            print("Could not open %s. File used by another process.\nPlease "\
+                  "make sure you exit all processes that might use any SDK "\
+                  "binaries." % e)
+        else:
+            print("Could not open %s: %s(%d)" % (e, ioex.strerror, ioex.errno))
+        sys.exit(-1)
+
+    ei_mag0,ei_mag1_3,ei_class,ei_data,ei_version = struct.unpack("<B3sBBB9x", e_ident)
+
+    if (ei_mag0 != 0x7f and ei_mag1_3 != "ELF") or ei_class == 0:
+        print("ERROR: unknow %s" % dl_path)
+        sys.exit(-1)
+
+    if ei_class == 1:
+        arch = 32
+    elif ei_class == 2:
+        arch = 64
+
+    return arch
+
+
 def parse_elf_header():
     global e_type, e_machine, e_version, e_entry, e_phoff, e_shoff, e_flags,\
            e_ehsize, e_phentsize, e_phnum, e_shentsize, e_shnum, e_shstrndx
@@ -223,6 +251,8 @@ else:
 
 executables_list = sys.argv[3:]
 
+dl_arch = get_dl_arch(new_dl_path)
+
 errors = False
 for e in executables_list:
     perms = os.stat(e)[stat.ST_MODE]
@@ -247,7 +277,7 @@ for e in executables_list:
     old_size = os.path.getsize(e)
     if old_size >= 64:
         arch = get_arch()
-        if arch:
+        if arch and arch == dl_arch:
             parse_elf_header()
             if not change_interpreter(e):
                 errors = True