From: H.J. Lu <hjl.tools@gmail.com>
Date: Fri, 29 Sep 2017 23:23:18 +0000 (-0700)
Subject: arm: Update elf_machine_load_address for static PIE
X-Git-Tag: glibc-2.27~833
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=8172aad937f52fe4ae891a206492150815791f2a;p=thirdparty%2Fglibc.git

arm: Update elf_machine_load_address for static PIE

When --enable-static-pie is used to configure glibc, we need to use
_dl_relocate_static_pie to compute load address in static PIE.

	* sysdeps/arm/dl-machine.h (elf_machine_load_address): Use
	_dl_relocate_static_pie instead of _dl_start to compute load
	address in static PIE.  Return 0 if _DYNAMIC is undefined for
	static executable.
---

diff --git a/ChangeLog b/ChangeLog
index efd567ce34b..b6dbff0624b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2017-09-29  H.J. Lu  <hongjiu.lu@intel.com>
+
+	* sysdeps/arm/dl-machine.h (elf_machine_load_address): Use
+	_dl_relocate_static_pie instead of _dl_start to compute load
+	address in static PIE.  Return 0 if _DYNAMIC is undefined for
+	static executable.
+
 2017-09-29  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* sysdeps/mips/dl-machine.h (elf_machine_dynamic): Return 0 if
diff --git a/sysdeps/arm/dl-machine.h b/sysdeps/arm/dl-machine.h
index 7d733f2b1c2..efe2e1b3a3a 100644
--- a/sysdeps/arm/dl-machine.h
+++ b/sysdeps/arm/dl-machine.h
@@ -53,10 +53,20 @@ elf_machine_dynamic (void)
 static inline Elf32_Addr __attribute__ ((unused))
 elf_machine_load_address (void)
 {
+  Elf32_Addr pcrel_addr;
+#ifdef SHARED
   extern Elf32_Addr __dl_start (void *) asm ("_dl_start");
   Elf32_Addr got_addr = (Elf32_Addr) &__dl_start;
-  Elf32_Addr pcrel_addr;
   asm ("adr %0, _dl_start" : "=r" (pcrel_addr));
+#else
+  extern Elf32_Dyn _DYNAMIC[] __attribute__((weak, visibility ("hidden")));
+  if (!_DYNAMIC)
+    return 0;
+  extern Elf32_Addr __dl_relocate_static_pie (void *)
+    asm ("_dl_relocate_static_pie") attribute_hidden;
+  Elf32_Addr got_addr = (Elf32_Addr) &__dl_relocate_static_pie;
+  asm ("adr %0, _dl_relocate_static_pie" : "=r" (pcrel_addr));
+#endif
 #ifdef __thumb__
   /* Clear the low bit of the function address.