diff mbox series

[v4] ld.so: Initialize bootstrap_map.l_ld_readonly [BZ #28340]

Message ID 20211018183538.3981830-1-hjl.tools@gmail.com
State Committed
Commit 2ec99d8c42b2ff1a1231e4df462a0910a9b7fdef
Headers show
Series [v4] ld.so: Initialize bootstrap_map.l_ld_readonly [BZ #28340] | expand

Checks

Context Check Description
dj/TryBot-apply_patch success Patch applied to master at the time it was sent
dj/TryBot-32bit success Build for i686

Commit Message

H.J. Lu Oct. 18, 2021, 6:35 p.m. UTC
1. Define DL_RO_DYN_SECTION to initalize bootstrap_map.l_ld_readonly
before calling elf_get_dynamic_info to get dynamic info in bootstrap_map,
2. Define a single

static inline bool
dl_relocate_ld (const struct link_map *l)
{
  /* Don't relocate dynamic section if it is readonly  */
  return !(l->l_ld_readonly || DL_RO_DYN_SECTION);
}

This updates BZ #28340 fix.
---
 elf/rtld.c                       |  1 +
 sysdeps/generic/dl-relocate-ld.h | 11 ++---------
 sysdeps/generic/ldsodefs.h       | 10 ++++++++++
 sysdeps/mips/dl-relocate-ld.h    | 11 ++---------
 sysdeps/riscv/dl-relocate-ld.h   | 11 ++---------
 5 files changed, 17 insertions(+), 27 deletions(-)

Comments

Florian Weimer Oct. 19, 2021, 1:14 p.m. UTC | #1
* H. J. Lu via Libc-alpha:

> 1. Define DL_RO_DYN_SECTION to initalize bootstrap_map.l_ld_readonly
> before calling elf_get_dynamic_info to get dynamic info in bootstrap_map,
> 2. Define a single
>
> static inline bool
> dl_relocate_ld (const struct link_map *l)
> {
>   /* Don't relocate dynamic section if it is readonly  */
>   return !(l->l_ld_readonly || DL_RO_DYN_SECTION);
> }
>
> This updates BZ #28340 fix.
> ---
>  elf/rtld.c                       |  1 +
>  sysdeps/generic/dl-relocate-ld.h | 11 ++---------
>  sysdeps/generic/ldsodefs.h       | 10 ++++++++++
>  sysdeps/mips/dl-relocate-ld.h    | 11 ++---------
>  sysdeps/riscv/dl-relocate-ld.h   | 11 ++---------
>  5 files changed, 17 insertions(+), 27 deletions(-)

This looks okay to me.  Thanks.

Florian
diff mbox series

Patch

diff --git a/elf/rtld.c b/elf/rtld.c
index c66a1d00bc..b8ba2d8836 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -547,6 +547,7 @@  _dl_start (void *arg)
 
   /* Read our own dynamic section and fill in the info array.  */
   bootstrap_map.l_ld = (void *) bootstrap_map.l_addr + elf_machine_dynamic ();
+  bootstrap_map.l_ld_readonly = DL_RO_DYN_SECTION;
   elf_get_dynamic_info (&bootstrap_map, true, false);
 
 #if NO_TLS_OFFSET != 0
diff --git a/sysdeps/generic/dl-relocate-ld.h b/sysdeps/generic/dl-relocate-ld.h
index 5fae206db9..cfb86c2d6a 100644
--- a/sysdeps/generic/dl-relocate-ld.h
+++ b/sysdeps/generic/dl-relocate-ld.h
@@ -19,14 +19,7 @@ 
 #ifndef _DL_RELOCATE_LD_H
 #define _DL_RELOCATE_LD_H
 
-/* Return true if dynamic section in the shared library L should be
-   relocated.  */
-
-static inline bool
-dl_relocate_ld (const struct link_map *l)
-{
-  /* Don't relocate dynamic section if it is readonly  */
-  return !l->l_ld_readonly;
-}
+/* The dynamic section is writable.  */
+#define DL_RO_DYN_SECTION 0
 
 #endif /* _DL_RELOCATE_LD_H */
diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h
index 9ec1511bb0..0410f777a6 100644
--- a/sysdeps/generic/ldsodefs.h
+++ b/sysdeps/generic/ldsodefs.h
@@ -69,6 +69,16 @@  __BEGIN_DECLS
    `ElfW(TYPE)' is used in place of `Elf32_TYPE' or `Elf64_TYPE'.  */
 #define ELFW(type)	_ElfW (ELF, __ELF_NATIVE_CLASS, type)
 
+/* Return true if dynamic section in the shared library L should be
+   relocated.  */
+
+static inline bool
+dl_relocate_ld (const struct link_map *l)
+{
+  /* Don't relocate dynamic section if it is readonly  */
+  return !(l->l_ld_readonly || DL_RO_DYN_SECTION);
+}
+
 /* All references to the value of l_info[DT_PLTGOT],
   l_info[DT_STRTAB], l_info[DT_SYMTAB], l_info[DT_RELA],
   l_info[DT_REL], l_info[DT_JMPREL], and l_info[VERSYMIDX (DT_VERSYM)]
diff --git a/sysdeps/mips/dl-relocate-ld.h b/sysdeps/mips/dl-relocate-ld.h
index 0c18d9a567..376ad75dd1 100644
--- a/sysdeps/mips/dl-relocate-ld.h
+++ b/sysdeps/mips/dl-relocate-ld.h
@@ -19,14 +19,7 @@ 
 #ifndef _DL_RELOCATE_LD_H
 #define _DL_RELOCATE_LD_H
 
-/* Return true if dynamic section in the shared library L should be
-   relocated.  */
-
-static inline bool
-dl_relocate_ld (const struct link_map *l)
-{
-  /* Never relocate dynamic section.  */
-  return false;
-}
+/* The dynamic section is readonly.  */
+#define DL_RO_DYN_SECTION 1
 
 #endif /* _DL_RELOCATE_LD_H */
diff --git a/sysdeps/riscv/dl-relocate-ld.h b/sysdeps/riscv/dl-relocate-ld.h
index 10327454b1..2ab2b8ac6c 100644
--- a/sysdeps/riscv/dl-relocate-ld.h
+++ b/sysdeps/riscv/dl-relocate-ld.h
@@ -19,14 +19,7 @@ 
 #ifndef _DL_RELOCATE_LD_H
 #define _DL_RELOCATE_LD_H
 
-/* Return true if dynamic section in the shared library L should be
-   relocated.  */
-
-static inline bool
-dl_relocate_ld (const struct link_map *l)
-{
-  /* Never relocate dynamic section for ABI compatibility.  */
-  return false;
-}
+/* The dynamic section is readonly for ABI compatibility.  */
+#define DL_RO_DYN_SECTION 1
 
 #endif /* _DL_RELOCATE_LD_H */