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