asan: readelf buffer overflow and abort

* elfcomm.c (byte_put_little_endian, byte_put_big_endian): Support
	more field sizes.
	* readelf.c (target_specific_reloc_handling <MSP430>): Limit
	allowed reloc_size.  Don't read_leb128 outside of section.
This commit is contained in:
Alan Modra 2020-09-25 10:05:57 +09:30
parent cc9ea2c21c
commit 5a805384b8
3 changed files with 24 additions and 51 deletions

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@ -1,3 +1,10 @@
2020-09-25 Alan Modra <amodra@gmail.com>
* elfcomm.c (byte_put_little_endian, byte_put_big_endian): Support
more field sizes.
* readelf.c (target_specific_reloc_handling <MSP430>): Limit
allowed reloc_size. Don't read_leb128 outside of section.
2020-09-23 Mark Wielaard <mark@klomp.org>
* dwarf.c (process_debug_info): Print Unit Type for DWARF5.

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@ -67,66 +67,31 @@ void (*byte_put) (unsigned char *, elf_vma, int);
void
byte_put_little_endian (unsigned char * field, elf_vma value, int size)
{
switch (size)
if (size <= 0 || size > 8)
{
case 8:
field[7] = (((value >> 24) >> 24) >> 8) & 0xff;
field[6] = ((value >> 24) >> 24) & 0xff;
field[5] = ((value >> 24) >> 16) & 0xff;
field[4] = ((value >> 24) >> 8) & 0xff;
/* Fall through. */
case 4:
field[3] = (value >> 24) & 0xff;
/* Fall through. */
case 3:
field[2] = (value >> 16) & 0xff;
/* Fall through. */
case 2:
field[1] = (value >> 8) & 0xff;
/* Fall through. */
case 1:
field[0] = value & 0xff;
break;
default:
error (_("Unhandled data length: %d\n"), size);
abort ();
}
while (size--)
{
*field++ = value & 0xff;
value >>= 8;
}
}
void
byte_put_big_endian (unsigned char * field, elf_vma value, int size)
{
switch (size)
if (size <= 0 || size > 8)
{
case 8:
field[7] = value & 0xff;
field[6] = (value >> 8) & 0xff;
field[5] = (value >> 16) & 0xff;
field[4] = (value >> 24) & 0xff;
value >>= 16;
value >>= 16;
/* Fall through. */
case 4:
field[3] = value & 0xff;
value >>= 8;
/* Fall through. */
case 3:
field[2] = value & 0xff;
value >>= 8;
/* Fall through. */
case 2:
field[1] = value & 0xff;
value >>= 8;
/* Fall through. */
case 1:
field[0] = value & 0xff;
break;
default:
error (_("Unhandled data length: %d\n"), size);
abort ();
}
while (size--)
{
field[size] = value & 0xff;
value >>= 8;
}
}
elf_vma (*byte_get) (const unsigned char *, int);

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@ -12622,7 +12622,7 @@ target_specific_reloc_handling (Filedata * filedata,
if (saved_sym != NULL)
{
bfd_vma value;
unsigned int reloc_size;
unsigned int reloc_size = 0;
int leb_ret = 0;
switch (reloc_type)
{
@ -12631,15 +12631,16 @@ target_specific_reloc_handling (Filedata * filedata,
break;
case 11: /* R_MSP430_GNU_SET_ULEB128 */
case 22: /* R_MSP430X_GNU_SET_ULEB128 */
read_leb128 (start + reloc->r_offset, end, FALSE,
&reloc_size, &leb_ret);
if (reloc->r_offset < (size_t) (end - start))
read_leb128 (start + reloc->r_offset, end, FALSE,
&reloc_size, &leb_ret);
break;
default:
reloc_size = 2;
break;
}
if (leb_ret != 0)
if (leb_ret != 0 || reloc_size == 0 || reloc_size > 8)
error (_("MSP430 ULEB128 field at 0x%lx contains invalid "
"ULEB128 value\n"),
(long) reloc->r_offset);