Toolchain/binutils-gdb
1
0
Fork 0
forked from Imagelibrary/binutils-gdb
Code Pull Requests Activity

Have readelf warn users if it is asked to decode a LLVM bitcode file or a golang object file.

Browse Source 
* readelf.c (check_magic_number): New function.  Checks the magic
	bytes at the start of a file.  If they are not the ELF format
	magic values, then attempts to generate a helpful error message.
	(process_file_header): Call check_magic_number.
This commit is contained in:
Nick Clifton
2022-08-22 11:15:40 +01:00
parent ba86e75013
commit 521f726815
2 changed files with 67 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

69
binutils/readelf.c
View File

@@ -5688,6 +5688,64 @@ get_data_encoding (unsigned int encoding)
}
}
static bool
check_magic_number (Filedata * filedata, Elf_Internal_Ehdr * header)
{
if (header->e_ident[EI_MAG0] == ELFMAG0
&& header->e_ident[EI_MAG1] == ELFMAG1
&& header->e_ident[EI_MAG2] == ELFMAG2
&& header->e_ident[EI_MAG3] == ELFMAG3)
return true;
/* Some compilers produce object files that are not in the ELF file format.
As an aid to users of readelf, try to identify these cases and suggest
alternative tools.
FIXME: It is not clear if all four bytes are used as constant magic
valus by all compilers. It may be necessary to recode this function if
different tools use different length sequences. */
static struct
{
unsigned char magic[4];
const char * obj_message;
const char * ar_message;
}
known_magic[] =
{
{ { 'B', 'C', 0xc0, 0xde },
N_("This is a LLVM bitcode file - try using llvm-bcanalyzer\n"),
N_("This is a LLVM bitcode file - try extracing and then using llvm-bcanalyzer\n")
},
{ { 'g', 'o', ' ', 'o' },
N_("This is a GO binary file - try using 'go tool objdump' or 'go tool nm'\n"),
NULL
}
};
int i;
for (i = ARRAY_SIZE (known_magic); i--;)
{
if (header->e_ident[EI_MAG0] == known_magic[i].magic[0]
&& header->e_ident[EI_MAG1] == known_magic[i].magic[1]
&& header->e_ident[EI_MAG2] == known_magic[i].magic[2]
&& header->e_ident[EI_MAG3] == known_magic[i].magic[3])
{
/* Some compiler's analyzer tools do not handle archives,
so we provide two different kinds of error message. */
if (filedata->archive_file_size > 0
&& known_magic[i].ar_message != NULL)
error (known_magic[i].ar_message);
else
error (known_magic[i].obj_message);
return false;
}
}
error (_("Not an ELF file - it has the wrong magic bytes at the start\n"));
return false;
}
/* Decode the data held in 'filedata->file_header'. */
static bool
@@ -5695,15 +5753,8 @@ process_file_header (Filedata * filedata)
{
Elf_Internal_Ehdr * header = & filedata->file_header;
if ( header->e_ident[EI_MAG0] != ELFMAG0
|| header->e_ident[EI_MAG1] != ELFMAG1
|| header->e_ident[EI_MAG2] != ELFMAG2
|| header->e_ident[EI_MAG3] != ELFMAG3)
{
error
(_("Not an ELF file - it has the wrong magic bytes at the start\n"));
return false;
}
if (! check_magic_number (filedata, header))
return false;
if (! filedata->is_separate)
init_dwarf_regnames_by_elf_machine_code (header->e_machine);