lib/glibc
1
0
Fork 0
mirror of https://sourceware.org/git/glibc.git synced 2026-01-06 11:51:29 +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

10
sysdeps/arc/dl-machine.h
View File

@@ -30,6 +30,8 @@
#include <string.h>
#include <link.h>
#include <dl-tls.h>
#include <dl-static-tls.h>
#include <dl-machine-rel.h>
/* Dynamic Linking ABI for ARCv2 ISA.
@@ -203,10 +205,6 @@ __start: \n\
/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries. */
#define ELF_MACHINE_JMP_SLOT R_ARC_JUMP_SLOT
/* ARC uses Rela relocations. */
#define ELF_MACHINE_NO_REL 1
#define ELF_MACHINE_NO_RELA 0
/* Fixup a PLT entry to bounce directly to the function at VALUE. */
static inline ElfW(Addr)
@@ -318,7 +316,7 @@ elf_machine_rela (struct link_map *map, struct r_scope_elem *scope[],
}
}
inline void
static inline void
__attribute__ ((always_inline))
elf_machine_rela_relative (ElfW(Addr) l_addr, const ElfW(Rela) *reloc,
void *const reloc_addr_arg)
@@ -327,7 +325,7 @@ elf_machine_rela_relative (ElfW(Addr) l_addr, const ElfW(Rela) *reloc,
*reloc_addr += l_addr;
}
inline void
static inline void
__attribute__ ((always_inline))
elf_machine_lazy_rel (struct link_map *map, struct r_scope_elem *scope[],
ElfW(Addr) l_addr, const ElfW(Rela) *reloc,