Line data    Source code

       1             : /* Update symbol information and section index in symbol table at the
       2             :    given index.
       3             :    Copyright (C) 2000, 2001, 2002, 2005, 2009, 2014, 2015 Red Hat, Inc.
       4             :    This file is part of elfutils.
       5             :    Written by Ulrich Drepper <drepper@redhat.com>, 2000.
       6             : 
       7             :    This file is free software; you can redistribute it and/or modify
       8             :    it under the terms of either
       9             : 
      10             :      * the GNU Lesser General Public License as published by the Free
      11             :        Software Foundation; either version 3 of the License, or (at
      12             :        your option) any later version
      13             : 
      14             :    or
      15             : 
      16             :      * the GNU General Public License as published by the Free
      17             :        Software Foundation; either version 2 of the License, or (at
      18             :        your option) any later version
      19             : 
      20             :    or both in parallel, as here.
      21             : 
      22             :    elfutils is distributed in the hope that it will be useful, but
      23             :    WITHOUT ANY WARRANTY; without even the implied warranty of
      24             :    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      25             :    General Public License for more details.
      26             : 
      27             :    You should have received copies of the GNU General Public License and
      28             :    the GNU Lesser General Public License along with this program.  If
      29             :    not, see <http://www.gnu.org/licenses/>.  */
      30             : 
      31             : #ifdef HAVE_CONFIG_H
      32             : # include <config.h>
      33             : #endif
      34             : 
      35             : #include <gelf.h>
      36             : #include <stdlib.h>
      37             : #include <string.h>
      38             : 
      39             : #include "libelfP.h"
      40             : 
      41             : 
      42             : int
      43        3932 : gelf_update_symshndx (Elf_Data *symdata, Elf_Data *shndxdata, int ndx,
      44             :                       GElf_Sym *src, Elf32_Word srcshndx)
      45             : {
      46        3932 :   Elf_Data_Scn *symdata_scn = (Elf_Data_Scn *) symdata;
      47        3932 :   Elf_Data_Scn *shndxdata_scn = (Elf_Data_Scn *) shndxdata;
      48             :   Elf_Scn *scn;
      49        3932 :   Elf32_Word *shndx = NULL;
      50        3932 :   int result = 0;
      51             : 
      52        3932 :   if (symdata == NULL)
      53             :     return 0;
      54             : 
      55        3932 :   if (unlikely (symdata_scn->d.d_type != ELF_T_SYM))
      56             :     {
      57             :       /* The type of the data better should match.  */
      58           0 :       __libelf_seterrno (ELF_E_DATA_MISMATCH);
      59           0 :       return 0;
      60             :     }
      61             : 
      62        3932 :   scn = symdata_scn->s;
      63             :   /* We simply have to believe the user that the two sections belong to
      64             :      the same ELF file.  */
      65        3932 :   rwlock_wrlock (scn->elf->lock);
      66             : 
      67             :   /* The user is not required to pass a data descriptor for an extended
      68             :      section index table.  */
      69        3932 :   if (shndxdata_scn != NULL)
      70             :     {
      71           0 :       if (unlikely ((ndx + 1) * sizeof (Elf32_Word) > shndxdata_scn->d.d_size))
      72             :         {
      73           0 :           __libelf_seterrno (ELF_E_INVALID_INDEX);
      74           0 :           goto out;
      75             :         }
      76             : 
      77           0 :       shndx = &((Elf32_Word *) shndxdata_scn->d.d_buf)[ndx];
      78             :     }
      79             :   /* But if s/he does not the extended sectio index must be zero.  */
      80        3932 :   else if (unlikely (srcshndx != 0))
      81             :     {
      82           0 :       __libelf_seterrno (ELF_E_INVALID_INDEX);
      83           0 :       goto out;
      84             :     }
      85             : 
      86        3932 :   if (scn->elf->class == ELFCLASS32)
      87             :     {
      88             :       Elf32_Sym *sym;
      89             : 
      90             :       /* There is the possibility that the values in the input are
      91             :          too large.  */
      92        1156 :       if (unlikely (src->st_value > 0xffffffffull)
      93        1156 :           || unlikely (src->st_size > 0xffffffffull))
      94             :         {
      95           0 :           __libelf_seterrno (ELF_E_INVALID_DATA);
      96           0 :           goto out;
      97             :         }
      98             : 
      99             :       /* Check whether we have to resize the data buffer.  */
     100        1156 :       if (INVALID_NDX (ndx, Elf32_Sym, &symdata_scn->d))
     101             :         {
     102           0 :           __libelf_seterrno (ELF_E_INVALID_INDEX);
     103           0 :           goto out;
     104             :         }
     105             : 
     106        1156 :       sym = &((Elf32_Sym *) symdata_scn->d.d_buf)[ndx];
     107             : 
     108             : #define COPY(name) \
     109             :       sym->name = src->name
     110        1156 :       COPY (st_name);
     111        1156 :       COPY (st_value);
     112        1156 :       COPY (st_size);
     113             :       /* Please note that we can simply copy the `st_info' element since
     114             :          the definitions of ELFxx_ST_BIND and ELFxx_ST_TYPE are the same
     115             :          for the 64 bit variant.  */
     116        1156 :       COPY (st_info);
     117        1156 :       COPY (st_other);
     118        1156 :       COPY (st_shndx);
     119             :     }
     120             :   else
     121             :     {
     122             :       /* Check whether we have to resize the data buffer.  */
     123        2776 :       if (INVALID_NDX (ndx, Elf64_Sym, &symdata_scn->d))
     124             :         {
     125           0 :           __libelf_seterrno (ELF_E_INVALID_INDEX);
     126           0 :           goto out;
     127             :         }
     128             : 
     129        2776 :       ((Elf64_Sym *) symdata_scn->d.d_buf)[ndx] = *src;
     130             :     }
     131             : 
     132             :   /* Now we can store the section index.  */
     133        3932 :   if (shndx != NULL)
     134           0 :     *shndx = srcshndx;
     135             : 
     136        3932 :   result = 1;
     137             : 
     138             :   /* Mark the section as modified.  */
     139        3932 :   scn->flags |= ELF_F_DIRTY;
     140             : 
     141        3932 :  out:
     142             :   rwlock_unlock (scn->elf->lock);
     143             : 
     144        3932 :   return result;
     145             : }