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From: Florian Weimer <fweimer@redhat.com>
To: libc-alpha@sourceware.org
Subject: [PATCH v2 12/32] elf: Move __rtld_malloc_init_stubs call into _dl_start_final
Date: Fri, 07 Jul 2023 20:48:23 +0200	[thread overview]
Message-ID: <901e4c1a17ffbec769b9c891e3781ccde238ad6c.1688741159.git.fweimer@redhat.com> (raw)
In-Reply-To: <cover.1688741159.git.fweimer@redhat.com>

Calling an extern function in a different translation unit before
self-relocation is brittle.  The compiler may load the address
at an earlier point in _dl_start, before self-relocation.  In
_dl_start_final, the call is behidn a compiler barrier, so this
cannot happen.
---
 elf/rtld.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/elf/rtld.c b/elf/rtld.c
index 54a7ade886..4624d99570 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -452,6 +452,8 @@ _dl_start_final (void *arg, struct dl_start_final_info *info)
 {
   ElfW(Addr) start_addr;
 
+  __rtld_malloc_init_stubs ();
+
   /* Do not use an initializer for these members because it would
      interfere with __rtld_static_init.  */
   GLRO (dl_find_object) = &_dl_find_object;
@@ -575,8 +577,6 @@ _dl_start (void *arg)
      function, that way the compiler cannot put accesses to the GOT
      before ELF_DYNAMIC_RELOCATE.  */
 
-  __rtld_malloc_init_stubs ();
-
 #ifdef DONT_USE_BOOTSTRAP_MAP
   return _dl_start_final (arg);
 #else
-- 
2.41.0



  parent reply	other threads:[~2023-07-07 18:48 UTC|newest]

Thread overview: 33+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-07-07 18:47 [PATCH v2 00/32] RELRO link maps Florian Weimer
2023-07-07 18:47 ` [PATCH v2 01/32] support: Add <support/memprobe.h> for protection flags probing Florian Weimer
2023-07-07 18:47 ` [PATCH v2 02/32] misc: Enable internal use of memory protection keys Florian Weimer
2023-07-07 18:47 ` [PATCH v2 03/32] elf: Remove _dl_sysdep_open_object hook function Florian Weimer
2023-07-07 18:47 ` [PATCH v2 04/32] elf: Eliminate second loop in find_version in dl-version.c Florian Weimer
2023-07-07 18:47 ` [PATCH v2 05/32] elf: In rtld_setup_main_map, assume ld.so has a DYNAMIC segment Florian Weimer
2023-07-07 18:47 ` [PATCH v2 06/32] elf: Remove version assert in check_match in elf/dl-lookup.c Florian Weimer
2023-07-07 18:48 ` [PATCH v2 07/32] elf: Disambiguate some failures in _dl_load_cache_lookup Florian Weimer
2023-07-07 18:48 ` [PATCH v2 08/32] elf: Eliminate alloca in open_verify Florian Weimer
2023-07-07 18:48 ` [PATCH v2 09/32] Do not export <alloc_buffer.h> functions from libc Florian Weimer
2023-07-07 18:48 ` [PATCH v2 10/32] elf: Make <alloc_buffer.h> usable in ld.so Florian Weimer
2023-07-07 18:48 ` [PATCH v2 11/32] elf: Merge the three implementations of _dl_dst_substitute Florian Weimer
2023-07-07 18:48 ` Florian Weimer [this message]
2023-07-07 18:48 ` [PATCH v2 13/32] elf: Merge __dl_libc_freemem into __rtld_libc_freeres Florian Weimer
2023-07-07 18:48 ` [PATCH v2 14/32] elf: Use struct link_map_private for the internal link map Florian Weimer
2023-07-07 18:48 ` [PATCH v2 15/32] elf: Remove run-time-writable fields from struct link_map_private Florian Weimer
2023-07-07 18:48 ` [PATCH v2 16/32] elf: Move l_tls_offset into read-write part of link map Florian Weimer
2023-07-07 18:48 ` [PATCH v2 17/32] elf: Allocate auditor state after read-write " Florian Weimer
2023-07-07 18:48 ` [PATCH v2 18/32] elf: Move link map fields used by dependency sorting to writable part Florian Weimer
2023-07-07 18:48 ` [PATCH v2 19/32] elf: Split _dl_lookup_map, _dl_map_new_object from _dl_map_object Florian Weimer
2023-07-07 18:48 ` [PATCH v2 20/32] elf: Add l_soname accessor function for DT_SONAME values Florian Weimer
2023-07-07 18:49 ` [PATCH v2 21/32] elf: _dl_rtld_map should not exist in static builds Florian Weimer
2023-07-07 18:49 ` [PATCH v2 22/32] elf: Introduce GLPM accessor for the protected memory area Florian Weimer
2023-07-07 18:49 ` [PATCH v2 23/32] elf: Bootstrap allocation for future protected memory allocator Florian Weimer
2023-07-07 18:49 ` [PATCH v2 24/32] elf: Implement a basic " Florian Weimer
2023-07-07 18:49 ` [PATCH v2 25/32] elf: Move most of the _dl_find_object data to the protected heap Florian Weimer
2023-07-07 18:49 ` [PATCH v2 26/32] elf: Switch to a region-based protected memory allocator Florian Weimer
2023-07-07 18:49 ` [PATCH v2 27/32] elf: Determine the caller link map in _dl_open Florian Weimer
2023-07-07 18:49 ` [PATCH v2 28/32] elf: Add fast path to dlopen for fully-opened maps Florian Weimer
2023-07-07 18:49 ` [PATCH v2 29/32] elf: Use _dl_find_object instead of _dl_find_dso_for_object in dlopen Florian Weimer
2023-07-07 18:50 ` [PATCH v2 30/32] elf: Put critical _dl_find_object pointers into protected memory area Florian Weimer
2023-07-07 19:08 ` [PATCH v2 31/32] elf: Add hash tables to speed up DT_NEEDED, dlopen lookups Florian Weimer
2023-07-07 19:08 ` [PATCH v2 32/32] elf: Use memory protection keys for the protected memory allocator Florian Weimer

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