More fixes for invalid memory accesses triggered by corrupt binaries.

PR binutils/17512
	* dwarf.c (get_encoded_value): Add an 'end' parameter.  Change the
	'data' parameter to a double pointer and return the updated value.
	(decode_location_expression): Update call to get_encoded_value.
	(frame_need_space): Handle the case where one or both of the
	mallocs fails.
	(read_cie): Initialise the cie pointer, even if the read fails.
	(display_debug_frames): Warn if the calculated block_end is before
	the start of the block.  Break the loop if the CIE could not be
	read.  Update call to get_encoded_value.  Warn if the read CFA
	expressions are too big.

	* ieee.c (ieee_archive_p) Skip processing if no bytes are read at
	all.
	(ieee_object_p): Likewise.
This commit is contained in:
Nick Clifton 2014-11-14 12:30:00 +00:00
parent 646da0594c
commit 041830e03c
4 changed files with 74 additions and 18 deletions

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@ -1,3 +1,10 @@
2014-11-14 Nick Clifton <nickc@redhat.com>
PR binutils/17512
* ieee.c (ieee_archive_p) Skip processing if no bytes are read at
all.
(ieee_object_p): Likewise.
2014-11-13 H.J. Lu <hongjiu.lu@intel.com>
* coffcode.h (coff_slurp_line_table): Add cast to unsigned int.

View File

@ -1312,7 +1312,8 @@ ieee_archive_p (bfd *abfd)
/* Ignore the return value here. It doesn't matter if we don't read
the entire buffer. We might have a very small ieee file. */
bfd_bread ((void *) buffer, (bfd_size_type) sizeof (buffer), abfd);
if (bfd_bread ((void *) buffer, (bfd_size_type) sizeof (buffer), abfd) <= 0)
goto got_wrong_format_error;
ieee->h.first_byte = buffer;
ieee->h.input_p = buffer;
@ -1801,7 +1802,8 @@ ieee_object_p (bfd *abfd)
goto fail;
/* Read the first few bytes in to see if it makes sense. Ignore
bfd_bread return value; The file might be very small. */
bfd_bread ((void *) buffer, (bfd_size_type) sizeof (buffer), abfd);
if (bfd_bread ((void *) buffer, (bfd_size_type) sizeof (buffer), abfd) <= 0)
goto got_wrong_format;
ieee->h.input_p = buffer;
if (this_byte_and_next (&(ieee->h)) != Module_Beginning)

View File

@ -1,3 +1,17 @@
2014-11-14 Nick Clifton <nickc@redhat.com>
PR binutils/17512
* dwarf.c (get_encoded_value): Add an 'end' parameter. Change the
'data' parameter to a double pointer and return the updated value.
(decode_location_expression): Update call to get_encoded_value.
(frame_need_space): Handle the case where one or both of the
mallocs fails.
(read_cie): Initialise the cie pointer, even if the read fails.
(display_debug_frames): Warn if the calculated block_end is before
the start of the block. Break the loop if the CIE could not be
read. Update call to get_encoded_value. Warn if the read CFA
expressions are too big.
2014-11-13 Nick Clifton <nickc@redhat.com>
PR binutils/17531

View File

@ -118,13 +118,22 @@ size_of_encoded_value (int encoding)
}
static dwarf_vma
get_encoded_value (unsigned char *data,
get_encoded_value (unsigned char **pdata,
int encoding,
struct dwarf_section *section)
struct dwarf_section *section,
unsigned char * end)
{
unsigned char * data = * pdata;
int size = size_of_encoded_value (encoding);
dwarf_vma val;
if (data + size >= end)
{
warn (_("Encoded value extends past end of section\n"));
* pdata = end;
return 0;
}
if (encoding & DW_EH_PE_signed)
val = byte_get_signed (data, size);
else
@ -132,6 +141,8 @@ get_encoded_value (unsigned char *data,
if ((encoding & 0x70) == DW_EH_PE_pcrel)
val += section->address + (data - section->start);
* pdata = data + size;
return val;
}
@ -1238,8 +1249,7 @@ decode_location_expression (unsigned char * data,
dwarf_vma addr;
encoding = *data++;
addr = get_encoded_value (data, encoding, section);
data += size_of_encoded_value (encoding);
addr = get_encoded_value (&data, encoding, section, end);
printf ("DW_OP_GNU_encoded_addr: fmt:%02x addr:", encoding);
print_dwarf_vma (addr, pointer_size);
@ -5068,6 +5078,14 @@ frame_need_space (Frame_Chunk *fc, unsigned int reg)
fc->col_type = (short int *) xcrealloc (fc->col_type, fc->ncols,
sizeof (short int));
fc->col_offset = (int *) xcrealloc (fc->col_offset, fc->ncols, sizeof (int));
/* PR 17512: file:002-10025-0.005. */
if (fc->col_type == NULL || fc->col_offset == NULL)
{
error (_("Out of memory allocating %u columns in dwarf frame arrays\n"),
fc->ncols);
fc->ncols = 0;
return -1;
}
while (prev < fc->ncols)
{
@ -5302,6 +5320,7 @@ read_cie (unsigned char *start, unsigned char *end,
unsigned char *augmentation_data = NULL;
unsigned long augmentation_data_len = 0;
* p_cie = NULL;
/* PR 17512: file: 001-228113-0.004. */
if (start >= end)
return end;
@ -5427,6 +5446,7 @@ display_debug_frames (struct dwarf_section *section,
saved_start = start;
SAFE_BYTE_GET_AND_INC (length, start, 4, end);
if (length == 0)
{
printf ("\n%08lx ZERO terminator\n\n",
@ -5447,7 +5467,7 @@ display_debug_frames (struct dwarf_section *section,
}
block_end = saved_start + length + initial_length_size;
if (block_end > end)
if (block_end > end || block_end < start)
{
warn ("Invalid length 0x%s in FDE at %#08lx\n",
dwarf_vmatoa_1 (NULL, length, offset_size),
@ -5465,6 +5485,9 @@ display_debug_frames (struct dwarf_section *section,
start = read_cie (start, end, &cie, &version,
&augmentation_data_len, &augmentation_data);
/* PR 17512: file: 027-135133-0.005. */
if (cie == NULL)
break;
fc = cie;
fc->next = chunks;
chunks = fc;
@ -5621,11 +5644,9 @@ display_debug_frames (struct dwarf_section *section,
segment_selector = 0;
if (fc->segment_size)
{
SAFE_BYTE_GET_AND_INC (segment_selector, start, fc->segment_size, end);
}
fc->pc_begin = get_encoded_value (start, fc->fde_encoding, section);
start += encoded_ptr_size;
SAFE_BYTE_GET_AND_INC (segment_selector, start, fc->segment_size, end);
fc->pc_begin = get_encoded_value (&start, fc->fde_encoding, section, end);
/* FIXME: It appears that sometimes the final pc_range value is
encoded in less than encoded_ptr_size bytes. See the x86_64
@ -5680,8 +5701,8 @@ display_debug_frames (struct dwarf_section *section,
while (start < block_end)
{
unsigned op, opa;
unsigned long reg, temp;
unsigned int reg, op, opa;
unsigned long temp;
op = *start++;
opa = op & 0x3f;
@ -5753,13 +5774,26 @@ display_debug_frames (struct dwarf_section *section,
break;
case DW_CFA_def_cfa_expression:
temp = LEB ();
start += temp;
if (start + temp < start)
{
warn (_("Corrupt CFA_def expression value: %lu\n"), temp);
start = block_end;
}
else
start += temp;
break;
case DW_CFA_expression:
case DW_CFA_val_expression:
reg = LEB ();
temp = LEB ();
start += temp;
if (start + temp < start)
{
/* PR 17512: file:306-192417-0.005. */
warn (_("Corrupt CFA expression value: %lu\n"), temp);
start = block_end;
}
else
start += temp;
if (frame_need_space (fc, reg) >= 0)
fc->col_type[reg] = DW_CFA_undefined;
break;
@ -5859,8 +5893,7 @@ display_debug_frames (struct dwarf_section *section,
break;
case DW_CFA_set_loc:
vma = get_encoded_value (start, fc->fde_encoding, section);
start += encoded_ptr_size;
vma = get_encoded_value (&start, fc->fde_encoding, section, end);
if (do_debug_frames_interp)
frame_display_row (fc, &need_col_headers, &max_regs);
else