lib/glibc
1
0
Fork 0
mirror of https://sourceware.org/git/glibc.git synced 2025-08-08 17:42:12 +03:00
Code Activity

elf: Fix dynamic-link.h usage on rtld.c

Browse Source 
The 4af6982e4c fix does not fully handle RTLD_BOOTSTRAP usage on
rtld.c due two issues:

  1. RTLD_BOOTSTRAP is also used on dl-machine.h on various
     architectures and it changes the semantics of various machine
     relocation functions.

  2. The elf_get_dynamic_info() change was done sideways, previously
     to 490e6c62aa get-dynamic-info.h was included by the first
     dynamic-link.h include *without* RTLD_BOOTSTRAP being defined.
     It means that the code within elf_get_dynamic_info() that uses
     RTLD_BOOTSTRAP is in fact unused.

To fix 1. this patch now includes dynamic-link.h only once with
RTLD_BOOTSTRAP defined.  The ELF_DYNAMIC_RELOCATE call will now have
the relocation fnctions with the expected semantics for the loader.

And to fix 2. part of 4af6982e4c is reverted (the check argument
elf_get_dynamic_info() is not required) and the RTLD_BOOTSTRAP
pieces are removed.

To reorganize the includes the static TLS definition is moved to
its own header to avoid a circular dependency (it is defined on
dynamic-link.h and dl-machine.h requires it at same time other
dynamic-link.h definition requires dl-machine.h defitions).

Also ELF_MACHINE_NO_REL, ELF_MACHINE_NO_RELA, and ELF_MACHINE_PLT_REL
are moved to its own header.  Only ancient ABIs need special values
(arm, i386, and mips), so a generic one is used as default.

The powerpc Elf64_FuncDesc is also moved to its own header, since
csu code required its definition (which would require either include
elf/ folder or add a full path with elf/).

Checked on x86_64, i686, aarch64, armhf, powerpc64, powerpc32,
and powerpc64le.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
This commit is contained in:
Adhemerval Zanella
2021-10-13 09:49:34 -03:00
parent e59ced2384
commit d6d89608ac
36 changed files with 272 additions and 175 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
sysdeps/sparc/sparc32/dl-machine.h
View File

@@ -28,6 +28,8 @@
#include <tls.h>
#include <dl-plt.h>
#include <elf/dl-hwcaps.h>
#include <dl-static-tls.h>
#include <dl-machine-rel.h>
/* Return nonzero iff ELF header is compatible with the running host. */
static inline int
@@ -196,10 +198,6 @@ elf_machine_runtime_setup (struct link_map *l, struct r_scope_elem *scope[],
/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries. */
#define ELF_MACHINE_JMP_SLOT R_SPARC_JMP_SLOT
/* The SPARC never uses Elf32_Rel relocations. */
#define ELF_MACHINE_NO_REL 1
#define ELF_MACHINE_NO_RELA 0
/* Undo the sub %sp, 6*4, %sp; add %sp, 22*4, %o0 below to get at the
value we want in __libc_stack_end. */
#define DL_STACK_END(cookie) \

6
sysdeps/sparc/sparc64/dl-machine.h
View File

@@ -26,6 +26,8 @@
#include <ldsodefs.h>
#include <sysdep.h>
#include <dl-plt.h>
#include <dl-static-tls.h>
#include <dl-machine-rel.h>
#define ELF64_R_TYPE_ID(info) ((info) & 0xff)
#define ELF64_R_TYPE_DATA(info) ((info) >> 8)
@@ -118,10 +120,6 @@ elf_machine_plt_value (struct link_map *map, const Elf64_Rela *reloc,
/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries. */
#define ELF_MACHINE_JMP_SLOT R_SPARC_JMP_SLOT
/* The SPARC never uses Elf64_Rel relocations. */
#define ELF_MACHINE_NO_REL 1
#define ELF_MACHINE_NO_RELA 0
/* Set up the loaded object described by L so its unrelocated PLT
entries will jump to the on-demand fixup code in dl-runtime.c. */