From 96429bcc91a14f71b177ddc5e716de3069060f2c Mon Sep 17 00:00:00 2001
From: Florian Weimer <fweimer@redhat.com>
Date: Sat, 1 Feb 2025 12:37:58 +0100
Subject: [PATCH] elf: Do not add a copy of _dl_find_object to libc.so

This reduces code size and dependencies on ld.so internals from
libc.so.

Fixes commit f4c142bb9fe6b02c0af8cfca8a920091e2dba44b
("arm: Use _dl_find_object on __gnu_Unwind_Find_exidx (BZ 31405)").

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
---
 elf/Makefile             | 2 +-
 elf/dl-find_object.c     | 5 ++---
 include/dlfcn.h          | 3 +--
 sysdeps/arm/find_exidx.c | 3 ++-
 4 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/elf/Makefile b/elf/Makefile
index 4b1d0d87411..5c833871d0c 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -34,7 +34,6 @@ routines = \
   dl-addr \
   dl-addr-obj \
   dl-early_allocate \
-  dl-find_object \
   dl-iteratephdr \
   dl-libc \
   dl-origin \
@@ -61,6 +60,7 @@ dl-routines = \
   dl-deps \
   dl-exception \
   dl-execstack \
+  dl-find_object \
   dl-fini \
   dl-init \
   dl-load \
diff --git a/elf/dl-find_object.c b/elf/dl-find_object.c
index 513e464011e..1e763732925 100644
--- a/elf/dl-find_object.c
+++ b/elf/dl-find_object.c
@@ -356,7 +356,7 @@ _dlfo_lookup (uintptr_t pc, struct dl_find_object_internal *first1, size_t size)
 }
 
 int
-__dl_find_object (void *pc1, struct dl_find_object *result)
+_dl_find_object (void *pc1, struct dl_find_object *result)
 {
   uintptr_t pc = (uintptr_t) pc1;
 
@@ -463,8 +463,7 @@ __dl_find_object (void *pc1, struct dl_find_object *result)
         return -1;
     } /* Transaction retry loop.  */
 }
-hidden_def (__dl_find_object)
-weak_alias (__dl_find_object, _dl_find_object)
+rtld_hidden_def (_dl_find_object)
 
 /* _dlfo_process_initial is called twice.  First to compute the array
    sizes from the initial loaded mappings.  Second to fill in the
diff --git a/include/dlfcn.h b/include/dlfcn.h
index f49ee1b0c99..a44420fa374 100644
--- a/include/dlfcn.h
+++ b/include/dlfcn.h
@@ -4,8 +4,7 @@
 #include <link.h>		/* For ElfW.  */
 #include <stdbool.h>
 
-extern __typeof (_dl_find_object) __dl_find_object;
-hidden_proto (__dl_find_object)
+rtld_hidden_proto (_dl_find_object)
 
 /* Internally used flag.  */
 #define __RTLD_DLOPEN	0x80000000
diff --git a/sysdeps/arm/find_exidx.c b/sysdeps/arm/find_exidx.c
index 60021a072c4..468e016214f 100644
--- a/sysdeps/arm/find_exidx.c
+++ b/sysdeps/arm/find_exidx.c
@@ -15,6 +15,7 @@
    License along with the GNU C Library.  If not, see
    <https://www.gnu.org/licenses/>.  */
 
+#include <ldsodefs.h>
 #include <link.h>
 
 /* Find the exception index table containing PC.  */
@@ -23,7 +24,7 @@ _Unwind_Ptr
 __gnu_Unwind_Find_exidx (_Unwind_Ptr pc, int * pcount)
 {
   struct dl_find_object data;
-  if (__dl_find_object ((void *) pc, &data) < 0)
+  if (GLRO(dl_find_object) ((void *) pc, &data) < 0)
     return 0;
   *pcount = data.dlfo_eh_count;
   return (_Unwind_Ptr) data.dlfo_eh_frame;
-- 
2.47.2