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https://sourceware.org/git/glibc.git
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fd96f06208
The test to call the indirect function now includes a subtest to checked whether the symbol is defined. When coming to that point this is almost always the case. The test for STT_GNU_IFUNC on the other hand rarely is true. Move it to the front means we don't have to perform the second test unless really necessary.
760 lines
24 KiB
C
760 lines
24 KiB
C
/* Machine-dependent ELF dynamic relocation inline functions. i386 version.
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Copyright (C) 1995-2005, 2006, 2009 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, write to the Free
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Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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02111-1307 USA. */
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#ifndef dl_machine_h
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#define dl_machine_h
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#define ELF_MACHINE_NAME "i386"
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#include <sys/param.h>
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#include <sysdep.h>
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#include <tls.h>
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#include <dl-tlsdesc.h>
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/* Return nonzero iff ELF header is compatible with the running host. */
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static inline int __attribute__ ((unused))
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elf_machine_matches_host (const Elf32_Ehdr *ehdr)
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{
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return ehdr->e_machine == EM_386;
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}
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#ifdef PI_STATIC_AND_HIDDEN
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/* Return the link-time address of _DYNAMIC. Conveniently, this is the
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first element of the GOT, a special entry that is never relocated. */
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static inline Elf32_Addr __attribute__ ((unused, const))
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elf_machine_dynamic (void)
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{
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/* This produces a GOTOFF reloc that resolves to zero at link time, so in
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fact just loads from the GOT register directly. By doing it without
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an asm we can let the compiler choose any register. */
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extern const Elf32_Addr _GLOBAL_OFFSET_TABLE_[] attribute_hidden;
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return _GLOBAL_OFFSET_TABLE_[0];
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}
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/* Return the run-time load address of the shared object. */
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static inline Elf32_Addr __attribute__ ((unused))
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elf_machine_load_address (void)
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{
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/* Compute the difference between the runtime address of _DYNAMIC as seen
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by a GOTOFF reference, and the link-time address found in the special
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unrelocated first GOT entry. */
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extern Elf32_Dyn bygotoff[] asm ("_DYNAMIC") attribute_hidden;
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return (Elf32_Addr) &bygotoff - elf_machine_dynamic ();
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}
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#else /* Without .hidden support, we can't compile the code above. */
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/* Return the link-time address of _DYNAMIC. Conveniently, this is the
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first element of the GOT. This must be inlined in a function which
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uses global data. */
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static inline Elf32_Addr __attribute__ ((unused))
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elf_machine_dynamic (void)
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{
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register Elf32_Addr *got asm ("%ebx");
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return *got;
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}
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/* Return the run-time load address of the shared object. */
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static inline Elf32_Addr __attribute__ ((unused))
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elf_machine_load_address (void)
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{
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/* It doesn't matter what variable this is, the reference never makes
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it to assembly. We need a dummy reference to some global variable
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via the GOT to make sure the compiler initialized %ebx in time. */
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extern int _dl_argc;
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Elf32_Addr addr;
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asm ("leal _dl_start@GOTOFF(%%ebx), %0\n"
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"subl _dl_start@GOT(%%ebx), %0"
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: "=r" (addr) : "m" (_dl_argc) : "cc");
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return addr;
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}
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#endif
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/* Set up the loaded object described by L so its unrelocated PLT
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entries will jump to the on-demand fixup code in dl-runtime.c. */
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static inline int __attribute__ ((unused, always_inline))
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elf_machine_runtime_setup (struct link_map *l, int lazy, int profile)
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{
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Elf32_Addr *got;
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extern void _dl_runtime_resolve (Elf32_Word) attribute_hidden;
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extern void _dl_runtime_profile (Elf32_Word) attribute_hidden;
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if (l->l_info[DT_JMPREL] && lazy)
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{
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/* The GOT entries for functions in the PLT have not yet been filled
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in. Their initial contents will arrange when called to push an
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offset into the .rel.plt section, push _GLOBAL_OFFSET_TABLE_[1],
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and then jump to _GLOBAL_OFFSET_TABLE[2]. */
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got = (Elf32_Addr *) D_PTR (l, l_info[DT_PLTGOT]);
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/* If a library is prelinked but we have to relocate anyway,
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we have to be able to undo the prelinking of .got.plt.
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The prelinker saved us here address of .plt + 0x16. */
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if (got[1])
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{
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l->l_mach.plt = got[1] + l->l_addr;
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l->l_mach.gotplt = (Elf32_Addr) &got[3];
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}
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got[1] = (Elf32_Addr) l; /* Identify this shared object. */
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/* The got[2] entry contains the address of a function which gets
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called to get the address of a so far unresolved function and
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jump to it. The profiling extension of the dynamic linker allows
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to intercept the calls to collect information. In this case we
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don't store the address in the GOT so that all future calls also
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end in this function. */
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if (__builtin_expect (profile, 0))
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{
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got[2] = (Elf32_Addr) &_dl_runtime_profile;
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if (GLRO(dl_profile) != NULL
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&& _dl_name_match_p (GLRO(dl_profile), l))
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/* This is the object we are looking for. Say that we really
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want profiling and the timers are started. */
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GL(dl_profile_map) = l;
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}
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else
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/* This function will get called to fix up the GOT entry indicated by
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the offset on the stack, and then jump to the resolved address. */
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got[2] = (Elf32_Addr) &_dl_runtime_resolve;
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}
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return lazy;
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}
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#ifdef IN_DL_RUNTIME
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# if !defined PROF && !__BOUNDED_POINTERS__
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/* We add a declaration of this function here so that in dl-runtime.c
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the ELF_MACHINE_RUNTIME_TRAMPOLINE macro really can pass the parameters
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in registers.
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We cannot use this scheme for profiling because the _mcount call
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destroys the passed register information. */
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/* GKM FIXME: Fix trampoline to pass bounds so we can do
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without the `__unbounded' qualifier. */
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#define ARCH_FIXUP_ATTRIBUTE __attribute__ ((regparm (3), stdcall, unused))
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extern ElfW(Addr) _dl_fixup (struct link_map *__unbounded l,
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ElfW(Word) reloc_offset)
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ARCH_FIXUP_ATTRIBUTE;
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extern ElfW(Addr) _dl_profile_fixup (struct link_map *l,
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ElfW(Word) reloc_offset,
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ElfW(Addr) retaddr, void *regs,
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long int *framesizep)
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ARCH_FIXUP_ATTRIBUTE;
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# endif
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#endif
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/* Mask identifying addresses reserved for the user program,
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where the dynamic linker should not map anything. */
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#define ELF_MACHINE_USER_ADDRESS_MASK 0xf8000000UL
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/* Initial entry point code for the dynamic linker.
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The C function `_dl_start' is the real entry point;
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its return value is the user program's entry point. */
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#define RTLD_START asm ("\n\
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.text\n\
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.align 16\n\
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0: movl (%esp), %ebx\n\
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ret\n\
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.align 16\n\
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.globl _start\n\
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.globl _dl_start_user\n\
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_start:\n\
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# Note that _dl_start gets the parameter in %eax.\n\
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movl %esp, %eax\n\
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call _dl_start\n\
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_dl_start_user:\n\
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# Save the user entry point address in %edi.\n\
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movl %eax, %edi\n\
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# Point %ebx at the GOT.\n\
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call 0b\n\
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addl $_GLOBAL_OFFSET_TABLE_, %ebx\n\
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# See if we were run as a command with the executable file\n\
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# name as an extra leading argument.\n\
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movl _dl_skip_args@GOTOFF(%ebx), %eax\n\
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# Pop the original argument count.\n\
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popl %edx\n\
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# Adjust the stack pointer to skip _dl_skip_args words.\n\
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leal (%esp,%eax,4), %esp\n\
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# Subtract _dl_skip_args from argc.\n\
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subl %eax, %edx\n\
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# Push argc back on the stack.\n\
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push %edx\n\
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# The special initializer gets called with the stack just\n\
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# as the application's entry point will see it; it can\n\
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# switch stacks if it moves these contents over.\n\
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" RTLD_START_SPECIAL_INIT "\n\
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# Load the parameters again.\n\
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# (eax, edx, ecx, *--esp) = (_dl_loaded, argc, argv, envp)\n\
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movl _rtld_local@GOTOFF(%ebx), %eax\n\
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leal 8(%esp,%edx,4), %esi\n\
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leal 4(%esp), %ecx\n\
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movl %esp, %ebp\n\
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# Make sure _dl_init is run with 16 byte aligned stack.\n\
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andl $-16, %esp\n\
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pushl %eax\n\
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pushl %eax\n\
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pushl %ebp\n\
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pushl %esi\n\
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# Clear %ebp, so that even constructors have terminated backchain.\n\
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xorl %ebp, %ebp\n\
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# Call the function to run the initializers.\n\
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call _dl_init_internal@PLT\n\
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# Pass our finalizer function to the user in %edx, as per ELF ABI.\n\
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leal _dl_fini@GOTOFF(%ebx), %edx\n\
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# Restore %esp _start expects.\n\
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movl (%esp), %esp\n\
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# Jump to the user's entry point.\n\
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jmp *%edi\n\
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.previous\n\
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");
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#ifndef RTLD_START_SPECIAL_INIT
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# define RTLD_START_SPECIAL_INIT /* nothing */
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#endif
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/* ELF_RTYPE_CLASS_PLT iff TYPE describes relocation of a PLT entry or
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TLS variable, so undefined references should not be allowed to
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define the value.
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ELF_RTYPE_CLASS_NOCOPY iff TYPE should not be allowed to resolve to one
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of the main executable's symbols, as for a COPY reloc. */
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#if !defined RTLD_BOOTSTRAP || USE___THREAD
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# define elf_machine_type_class(type) \
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((((type) == R_386_JMP_SLOT || (type) == R_386_TLS_DTPMOD32 \
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|| (type) == R_386_TLS_DTPOFF32 || (type) == R_386_TLS_TPOFF32 \
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|| (type) == R_386_TLS_TPOFF || (type) == R_386_TLS_DESC) \
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* ELF_RTYPE_CLASS_PLT) \
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| (((type) == R_386_COPY) * ELF_RTYPE_CLASS_COPY))
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#else
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# define elf_machine_type_class(type) \
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((((type) == R_386_JMP_SLOT) * ELF_RTYPE_CLASS_PLT) \
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| (((type) == R_386_COPY) * ELF_RTYPE_CLASS_COPY))
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#endif
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/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries. */
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#define ELF_MACHINE_JMP_SLOT R_386_JMP_SLOT
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/* The i386 never uses Elf32_Rela relocations for the dynamic linker.
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Prelinked libraries may use Elf32_Rela though. */
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#define ELF_MACHINE_PLT_REL 1
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/* We define an initialization functions. This is called very early in
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_dl_sysdep_start. */
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#define DL_PLATFORM_INIT dl_platform_init ()
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static inline void __attribute__ ((unused))
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dl_platform_init (void)
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{
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if (GLRO(dl_platform) != NULL && *GLRO(dl_platform) == '\0')
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/* Avoid an empty string which would disturb us. */
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GLRO(dl_platform) = NULL;
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}
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static inline Elf32_Addr
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elf_machine_fixup_plt (struct link_map *map, lookup_t t,
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const Elf32_Rel *reloc,
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Elf32_Addr *reloc_addr, Elf32_Addr value)
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{
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return *reloc_addr = value;
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}
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/* Return the final value of a plt relocation. */
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static inline Elf32_Addr
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elf_machine_plt_value (struct link_map *map, const Elf32_Rel *reloc,
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Elf32_Addr value)
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{
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return value;
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}
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/* Names of the architecture-specific auditing callback functions. */
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#define ARCH_LA_PLTENTER i86_gnu_pltenter
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#define ARCH_LA_PLTEXIT i86_gnu_pltexit
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#endif /* !dl_machine_h */
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/* The i386 never uses Elf32_Rela relocations for the dynamic linker.
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Prelinked libraries may use Elf32_Rela though. */
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#define ELF_MACHINE_NO_RELA defined RTLD_BOOTSTRAP
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#ifdef RESOLVE_MAP
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/* Perform the relocation specified by RELOC and SYM (which is fully resolved).
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MAP is the object containing the reloc. */
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auto inline void
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__attribute ((always_inline))
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elf_machine_rel (struct link_map *map, const Elf32_Rel *reloc,
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const Elf32_Sym *sym, const struct r_found_version *version,
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void *const reloc_addr_arg)
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{
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Elf32_Addr *const reloc_addr = reloc_addr_arg;
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const unsigned int r_type = ELF32_R_TYPE (reloc->r_info);
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# if !defined RTLD_BOOTSTRAP || !defined HAVE_Z_COMBRELOC
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if (__builtin_expect (r_type == R_386_RELATIVE, 0))
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{
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# if !defined RTLD_BOOTSTRAP && !defined HAVE_Z_COMBRELOC
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/* This is defined in rtld.c, but nowhere in the static libc.a;
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make the reference weak so static programs can still link.
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This declaration cannot be done when compiling rtld.c
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(i.e. #ifdef RTLD_BOOTSTRAP) because rtld.c contains the
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common defn for _dl_rtld_map, which is incompatible with a
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weak decl in the same file. */
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# ifndef SHARED
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weak_extern (_dl_rtld_map);
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# endif
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if (map != &GL(dl_rtld_map)) /* Already done in rtld itself. */
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# endif
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*reloc_addr += map->l_addr;
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}
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# ifndef RTLD_BOOTSTRAP
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else if (__builtin_expect (r_type == R_386_NONE, 0))
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return;
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# endif
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else
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# endif /* !RTLD_BOOTSTRAP and have no -z combreloc */
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{
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const Elf32_Sym *const refsym = sym;
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struct link_map *sym_map = RESOLVE_MAP (&sym, version, r_type);
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Elf32_Addr value = sym_map == NULL ? 0 : sym_map->l_addr + sym->st_value;
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if (sym != NULL
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&& __builtin_expect (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC,
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0)
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&& __builtin_expect (sym->st_shndx != SHN_UNDEF, 1))
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value = ((Elf32_Addr (*) (void)) value) ();
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switch (r_type)
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{
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case R_386_GLOB_DAT:
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case R_386_JMP_SLOT:
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*reloc_addr = value;
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break;
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# if !defined RTLD_BOOTSTRAP || USE___THREAD
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case R_386_TLS_DTPMOD32:
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# ifdef RTLD_BOOTSTRAP
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/* During startup the dynamic linker is always the module
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with index 1.
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XXX If this relocation is necessary move before RESOLVE
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call. */
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*reloc_addr = 1;
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# else
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/* Get the information from the link map returned by the
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resolv function. */
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if (sym_map != NULL)
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*reloc_addr = sym_map->l_tls_modid;
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# endif
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break;
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case R_386_TLS_DTPOFF32:
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# ifndef RTLD_BOOTSTRAP
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/* During relocation all TLS symbols are defined and used.
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Therefore the offset is already correct. */
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if (sym != NULL)
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*reloc_addr = sym->st_value;
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# endif
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break;
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case R_386_TLS_DESC:
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{
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struct tlsdesc volatile *td =
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(struct tlsdesc volatile *)reloc_addr;
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# ifndef RTLD_BOOTSTRAP
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if (! sym)
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td->entry = _dl_tlsdesc_undefweak;
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else
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# endif
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{
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# ifndef RTLD_BOOTSTRAP
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# ifndef SHARED
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CHECK_STATIC_TLS (map, sym_map);
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# else
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if (!TRY_STATIC_TLS (map, sym_map))
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{
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td->arg = _dl_make_tlsdesc_dynamic
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(sym_map, sym->st_value + (ElfW(Word))td->arg);
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td->entry = _dl_tlsdesc_dynamic;
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}
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else
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# endif
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# endif
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{
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td->arg = (void*)(sym->st_value - sym_map->l_tls_offset
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+ (ElfW(Word))td->arg);
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td->entry = _dl_tlsdesc_return;
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}
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}
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break;
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}
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case R_386_TLS_TPOFF32:
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/* The offset is positive, backward from the thread pointer. */
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# ifdef RTLD_BOOTSTRAP
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*reloc_addr += map->l_tls_offset - sym->st_value;
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# else
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/* We know the offset of object the symbol is contained in.
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It is a positive value which will be subtracted from the
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thread pointer. To get the variable position in the TLS
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block we subtract the offset from that of the TLS block. */
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if (sym != NULL)
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{
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CHECK_STATIC_TLS (map, sym_map);
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*reloc_addr += sym_map->l_tls_offset - sym->st_value;
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}
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# endif
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break;
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case R_386_TLS_TPOFF:
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/* The offset is negative, forward from the thread pointer. */
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# ifdef RTLD_BOOTSTRAP
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*reloc_addr += sym->st_value - map->l_tls_offset;
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# else
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/* We know the offset of object the symbol is contained in.
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It is a negative value which will be added to the
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thread pointer. */
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if (sym != NULL)
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{
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CHECK_STATIC_TLS (map, sym_map);
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*reloc_addr += sym->st_value - sym_map->l_tls_offset;
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}
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# endif
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break;
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# endif /* use TLS */
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# ifndef RTLD_BOOTSTRAP
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case R_386_32:
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*reloc_addr += value;
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break;
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case R_386_PC32:
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*reloc_addr += (value - (Elf32_Addr) reloc_addr);
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break;
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case R_386_COPY:
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if (sym == NULL)
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|
/* This can happen in trace mode if an object could not be
|
|
found. */
|
|
break;
|
|
if (__builtin_expect (sym->st_size > refsym->st_size, 0)
|
|
|| (__builtin_expect (sym->st_size < refsym->st_size, 0)
|
|
&& GLRO(dl_verbose)))
|
|
{
|
|
const char *strtab;
|
|
|
|
strtab = (const char *) D_PTR (map, l_info[DT_STRTAB]);
|
|
_dl_error_printf ("\
|
|
%s: Symbol `%s' has different size in shared object, consider re-linking\n",
|
|
rtld_progname ?: "<program name unknown>",
|
|
strtab + refsym->st_name);
|
|
}
|
|
memcpy (reloc_addr_arg, (void *) value,
|
|
MIN (sym->st_size, refsym->st_size));
|
|
break;
|
|
case R_386_IRELATIVE:
|
|
value = map->l_addr + *reloc_addr;
|
|
value = ((Elf32_Addr (*) (void)) value) ();
|
|
*reloc_addr = value;
|
|
break;
|
|
default:
|
|
_dl_reloc_bad_type (map, r_type, 0);
|
|
break;
|
|
# endif /* !RTLD_BOOTSTRAP */
|
|
}
|
|
}
|
|
}
|
|
|
|
# ifndef RTLD_BOOTSTRAP
|
|
auto inline void
|
|
__attribute__ ((always_inline))
|
|
elf_machine_rela (struct link_map *map, const Elf32_Rela *reloc,
|
|
const Elf32_Sym *sym, const struct r_found_version *version,
|
|
void *const reloc_addr_arg)
|
|
{
|
|
Elf32_Addr *const reloc_addr = reloc_addr_arg;
|
|
const unsigned int r_type = ELF32_R_TYPE (reloc->r_info);
|
|
|
|
if (ELF32_R_TYPE (reloc->r_info) == R_386_RELATIVE)
|
|
*reloc_addr = map->l_addr + reloc->r_addend;
|
|
else if (r_type != R_386_NONE)
|
|
{
|
|
# ifndef RESOLVE_CONFLICT_FIND_MAP
|
|
const Elf32_Sym *const refsym = sym;
|
|
# endif
|
|
struct link_map *sym_map = RESOLVE_MAP (&sym, version, r_type);
|
|
Elf32_Addr value = sym == NULL ? 0 : sym_map->l_addr + sym->st_value;
|
|
|
|
if (sym != NULL
|
|
&& __builtin_expect (sym->st_shndx != SHN_UNDEF, 1)
|
|
&& __builtin_expect (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC,
|
|
0))
|
|
value = ((Elf32_Addr (*) (void)) value) ();
|
|
|
|
switch (ELF32_R_TYPE (reloc->r_info))
|
|
{
|
|
case R_386_GLOB_DAT:
|
|
case R_386_JMP_SLOT:
|
|
case R_386_32:
|
|
*reloc_addr = value + reloc->r_addend;
|
|
break;
|
|
# ifndef RESOLVE_CONFLICT_FIND_MAP
|
|
/* Not needed for dl-conflict.c. */
|
|
case R_386_PC32:
|
|
*reloc_addr = (value + reloc->r_addend - (Elf32_Addr) reloc_addr);
|
|
break;
|
|
|
|
case R_386_TLS_DTPMOD32:
|
|
/* Get the information from the link map returned by the
|
|
resolv function. */
|
|
if (sym_map != NULL)
|
|
*reloc_addr = sym_map->l_tls_modid;
|
|
break;
|
|
case R_386_TLS_DTPOFF32:
|
|
/* During relocation all TLS symbols are defined and used.
|
|
Therefore the offset is already correct. */
|
|
*reloc_addr = (sym == NULL ? 0 : sym->st_value) + reloc->r_addend;
|
|
break;
|
|
case R_386_TLS_DESC:
|
|
{
|
|
struct tlsdesc volatile *td =
|
|
(struct tlsdesc volatile *)reloc_addr;
|
|
|
|
# ifndef RTLD_BOOTSTRAP
|
|
if (!sym)
|
|
{
|
|
td->arg = (void*)reloc->r_addend;
|
|
td->entry = _dl_tlsdesc_undefweak;
|
|
}
|
|
else
|
|
# endif
|
|
{
|
|
# ifndef RTLD_BOOTSTRAP
|
|
# ifndef SHARED
|
|
CHECK_STATIC_TLS (map, sym_map);
|
|
# else
|
|
if (!TRY_STATIC_TLS (map, sym_map))
|
|
{
|
|
td->arg = _dl_make_tlsdesc_dynamic
|
|
(sym_map, sym->st_value + reloc->r_addend);
|
|
td->entry = _dl_tlsdesc_dynamic;
|
|
}
|
|
else
|
|
# endif
|
|
# endif
|
|
{
|
|
td->arg = (void*)(sym->st_value - sym_map->l_tls_offset
|
|
+ reloc->r_addend);
|
|
td->entry = _dl_tlsdesc_return;
|
|
}
|
|
}
|
|
}
|
|
break;
|
|
case R_386_TLS_TPOFF32:
|
|
/* The offset is positive, backward from the thread pointer. */
|
|
/* We know the offset of object the symbol is contained in.
|
|
It is a positive value which will be subtracted from the
|
|
thread pointer. To get the variable position in the TLS
|
|
block we subtract the offset from that of the TLS block. */
|
|
if (sym != NULL)
|
|
{
|
|
CHECK_STATIC_TLS (map, sym_map);
|
|
*reloc_addr = sym_map->l_tls_offset - sym->st_value
|
|
+ reloc->r_addend;
|
|
}
|
|
break;
|
|
case R_386_TLS_TPOFF:
|
|
/* The offset is negative, forward from the thread pointer. */
|
|
/* We know the offset of object the symbol is contained in.
|
|
It is a negative value which will be added to the
|
|
thread pointer. */
|
|
if (sym != NULL)
|
|
{
|
|
CHECK_STATIC_TLS (map, sym_map);
|
|
*reloc_addr = sym->st_value - sym_map->l_tls_offset
|
|
+ reloc->r_addend;
|
|
}
|
|
break;
|
|
case R_386_COPY:
|
|
if (sym == NULL)
|
|
/* This can happen in trace mode if an object could not be
|
|
found. */
|
|
break;
|
|
if (__builtin_expect (sym->st_size > refsym->st_size, 0)
|
|
|| (__builtin_expect (sym->st_size < refsym->st_size, 0)
|
|
&& GLRO(dl_verbose)))
|
|
{
|
|
const char *strtab;
|
|
|
|
strtab = (const char *) D_PTR (map, l_info[DT_STRTAB]);
|
|
_dl_error_printf ("\
|
|
%s: Symbol `%s' has different size in shared object, consider re-linking\n",
|
|
rtld_progname ?: "<program name unknown>",
|
|
strtab + refsym->st_name);
|
|
}
|
|
memcpy (reloc_addr_arg, (void *) value,
|
|
MIN (sym->st_size, refsym->st_size));
|
|
break;
|
|
# endif /* !RESOLVE_CONFLICT_FIND_MAP */
|
|
case R_386_IRELATIVE:
|
|
value = map->l_addr + reloc->r_addend;
|
|
value = ((Elf32_Addr (*) (void)) value) ();
|
|
*reloc_addr = value;
|
|
break;
|
|
default:
|
|
/* We add these checks in the version to relocate ld.so only
|
|
if we are still debugging. */
|
|
_dl_reloc_bad_type (map, r_type, 0);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
# endif /* !RTLD_BOOTSTRAP */
|
|
|
|
auto inline void
|
|
__attribute ((always_inline))
|
|
elf_machine_rel_relative (Elf32_Addr l_addr, const Elf32_Rel *reloc,
|
|
void *const reloc_addr_arg)
|
|
{
|
|
Elf32_Addr *const reloc_addr = reloc_addr_arg;
|
|
assert (ELF32_R_TYPE (reloc->r_info) == R_386_RELATIVE);
|
|
*reloc_addr += l_addr;
|
|
}
|
|
|
|
# ifndef RTLD_BOOTSTRAP
|
|
auto inline void
|
|
__attribute__ ((always_inline))
|
|
elf_machine_rela_relative (Elf32_Addr l_addr, const Elf32_Rela *reloc,
|
|
void *const reloc_addr_arg)
|
|
{
|
|
Elf32_Addr *const reloc_addr = reloc_addr_arg;
|
|
*reloc_addr = l_addr + reloc->r_addend;
|
|
}
|
|
# endif /* !RTLD_BOOTSTRAP */
|
|
|
|
auto inline void
|
|
__attribute__ ((always_inline))
|
|
elf_machine_lazy_rel (struct link_map *map,
|
|
Elf32_Addr l_addr, const Elf32_Rel *reloc)
|
|
{
|
|
Elf32_Addr *const reloc_addr = (void *) (l_addr + reloc->r_offset);
|
|
const unsigned int r_type = ELF32_R_TYPE (reloc->r_info);
|
|
/* Check for unexpected PLT reloc type. */
|
|
if (__builtin_expect (r_type == R_386_JMP_SLOT, 1))
|
|
{
|
|
if (__builtin_expect (map->l_mach.plt, 0) == 0)
|
|
*reloc_addr += l_addr;
|
|
else
|
|
*reloc_addr = (map->l_mach.plt
|
|
+ (((Elf32_Addr) reloc_addr) - map->l_mach.gotplt) * 4);
|
|
}
|
|
else if (__builtin_expect (r_type == R_386_TLS_DESC, 1))
|
|
{
|
|
struct tlsdesc volatile * __attribute__((__unused__)) td =
|
|
(struct tlsdesc volatile *)reloc_addr;
|
|
|
|
/* Handle relocations that reference the local *ABS* in a simple
|
|
way, so as to preserve a potential addend. */
|
|
if (ELF32_R_SYM (reloc->r_info) == 0)
|
|
td->entry = _dl_tlsdesc_resolve_abs_plus_addend;
|
|
/* Given a known-zero addend, we can store a pointer to the
|
|
reloc in the arg position. */
|
|
else if (td->arg == 0)
|
|
{
|
|
td->arg = (void*)reloc;
|
|
td->entry = _dl_tlsdesc_resolve_rel;
|
|
}
|
|
else
|
|
{
|
|
/* We could handle non-*ABS* relocations with non-zero addends
|
|
by allocating dynamically an arg to hold a pointer to the
|
|
reloc, but that sounds pointless. */
|
|
const Elf32_Rel *const r = reloc;
|
|
/* The code below was borrowed from elf_dynamic_do_rel(). */
|
|
const ElfW(Sym) *const symtab =
|
|
(const void *) D_PTR (map, l_info[DT_SYMTAB]);
|
|
|
|
# ifdef RTLD_BOOTSTRAP
|
|
/* The dynamic linker always uses versioning. */
|
|
assert (map->l_info[VERSYMIDX (DT_VERSYM)] != NULL);
|
|
# else
|
|
if (map->l_info[VERSYMIDX (DT_VERSYM)])
|
|
# endif
|
|
{
|
|
const ElfW(Half) *const version =
|
|
(const void *) D_PTR (map, l_info[VERSYMIDX (DT_VERSYM)]);
|
|
ElfW(Half) ndx = version[ELFW(R_SYM) (r->r_info)] & 0x7fff;
|
|
elf_machine_rel (map, r, &symtab[ELFW(R_SYM) (r->r_info)],
|
|
&map->l_versions[ndx],
|
|
(void *) (l_addr + r->r_offset));
|
|
}
|
|
# ifndef RTLD_BOOTSTRAP
|
|
else
|
|
elf_machine_rel (map, r, &symtab[ELFW(R_SYM) (r->r_info)], NULL,
|
|
(void *) (l_addr + r->r_offset));
|
|
# endif
|
|
}
|
|
}
|
|
else if (__builtin_expect (r_type == R_386_IRELATIVE, 0))
|
|
{
|
|
Elf32_Addr value = map->l_addr + *reloc_addr;
|
|
value = ((Elf32_Addr (*) (void)) value) ();
|
|
*reloc_addr = value;
|
|
}
|
|
else
|
|
_dl_reloc_bad_type (map, r_type, 1);
|
|
}
|
|
|
|
# ifndef RTLD_BOOTSTRAP
|
|
|
|
auto inline void
|
|
__attribute__ ((always_inline))
|
|
elf_machine_lazy_rela (struct link_map *map,
|
|
Elf32_Addr l_addr, const Elf32_Rela *reloc)
|
|
{
|
|
Elf32_Addr *const reloc_addr = (void *) (l_addr + reloc->r_offset);
|
|
const unsigned int r_type = ELF32_R_TYPE (reloc->r_info);
|
|
if (__builtin_expect (r_type == R_386_JMP_SLOT, 1))
|
|
;
|
|
else if (__builtin_expect (r_type == R_386_TLS_DESC, 1))
|
|
{
|
|
struct tlsdesc volatile * __attribute__((__unused__)) td =
|
|
(struct tlsdesc volatile *)reloc_addr;
|
|
|
|
td->arg = (void*)reloc;
|
|
td->entry = _dl_tlsdesc_resolve_rela;
|
|
}
|
|
else if (__builtin_expect (r_type == R_386_IRELATIVE, 0))
|
|
{
|
|
Elf32_Addr value = map->l_addr + reloc->r_addend;
|
|
value = ((Elf32_Addr (*) (void)) value) ();
|
|
*reloc_addr = value;
|
|
}
|
|
else
|
|
_dl_reloc_bad_type (map, r_type, 1);
|
|
}
|
|
|
|
# endif /* !RTLD_BOOTSTRAP */
|
|
|
|
#endif /* RESOLVE_MAP */
|