* elf-bfd.h (struct cie): Use bfd_vmas for code_align, ra_column and
augmentation_size. Use bfd_signed_vmas for data_align. * elf-eh-frame.c (read_uleb128, read_sleb128): Delete in favor of... (read_byte, skip_leb128, read_uleb128, read_sleb128): ...these new functions. Don't read past the end of the enclosing CIE or FDE. (skip_bytes): New utility function. (_bfd_elf_discard_section_eh_frame): Use new functions, adding more sanity checking. (_bfd_elf_write_section_eh_frame): Use new functions.
This commit is contained in:
Richard Sandiford
parent
acfe556796
commit
2c42be6506
3 changed files with 143 additions and 56 deletions
|
|
@ -1,3 +1,15 @@
|
|||
2005-01-17 Richard Sandiford <rsandifo@redhat.com>
|
||||
|
||||
* elf-bfd.h (struct cie): Use bfd_vmas for code_align, ra_column and
|
||||
augmentation_size. Use bfd_signed_vmas for data_align.
|
||||
* elf-eh-frame.c (read_uleb128, read_sleb128): Delete in favor of...
|
||||
(read_byte, skip_leb128, read_uleb128, read_sleb128): ...these new
|
||||
functions. Don't read past the end of the enclosing CIE or FDE.
|
||||
(skip_bytes): New utility function.
|
||||
(_bfd_elf_discard_section_eh_frame): Use new functions, adding more
|
||||
sanity checking.
|
||||
(_bfd_elf_write_section_eh_frame): Use new functions.
|
||||
|
||||
2005-01-17 Richard Sandiford <rsandifo@redhat.com>
|
||||
|
||||
* elf-eh-frame.c (_bfd_elf_discard_section_eh_frame): Use an
|
||||
|
|
|
|||
|
|
@ -1,6 +1,6 @@
|
|||
/* BFD back-end data structures for ELF files.
|
||||
Copyright 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
|
||||
2002, 2003, 2004 Free Software Foundation, Inc.
|
||||
2002, 2003, 2004, 2005 Free Software Foundation, Inc.
|
||||
Written by Cygnus Support.
|
||||
|
||||
This file is part of BFD, the Binary File Descriptor library.
|
||||
|
|
@ -270,10 +270,10 @@ struct cie
|
|||
struct cie_header hdr;
|
||||
unsigned char version;
|
||||
unsigned char augmentation[20];
|
||||
unsigned int code_align;
|
||||
int data_align;
|
||||
unsigned int ra_column;
|
||||
unsigned int augmentation_size;
|
||||
bfd_vma code_align;
|
||||
bfd_signed_vma data_align;
|
||||
bfd_vma ra_column;
|
||||
bfd_vma augmentation_size;
|
||||
struct elf_link_hash_entry *personality;
|
||||
unsigned char per_encoding;
|
||||
unsigned char lsda_encoding;
|
||||
|
|
|
|||
|
|
@ -26,21 +26,85 @@
|
|||
|
||||
#define EH_FRAME_HDR_SIZE 8
|
||||
|
||||
#define read_uleb128(VAR, BUF) \
|
||||
do \
|
||||
{ \
|
||||
(VAR) = read_unsigned_leb128 (abfd, buf, &leb128_tmp); \
|
||||
(BUF) += leb128_tmp; \
|
||||
} \
|
||||
while (0)
|
||||
/* If *ITER hasn't reached END yet, read the next byte into *RESULT and
|
||||
move onto the next byte. Return true on success. */
|
||||
|
||||
#define read_sleb128(VAR, BUF) \
|
||||
do \
|
||||
{ \
|
||||
(VAR) = read_signed_leb128 (abfd, buf, &leb128_tmp); \
|
||||
(BUF) += leb128_tmp; \
|
||||
} \
|
||||
while (0)
|
||||
static inline bfd_boolean
|
||||
read_byte (bfd_byte **iter, bfd_byte *end, unsigned char *result)
|
||||
{
|
||||
if (*iter >= end)
|
||||
return FALSE;
|
||||
*result = *((*iter)++);
|
||||
return TRUE;
|
||||
}
|
||||
|
||||
/* Move *ITER over LENGTH bytes, or up to END, whichever is closer.
|
||||
Return true it was possible to move LENGTH bytes. */
|
||||
|
||||
static inline bfd_boolean
|
||||
skip_bytes (bfd_byte **iter, bfd_byte *end, bfd_size_type length)
|
||||
{
|
||||
if ((bfd_size_type) (end - *iter) < length)
|
||||
{
|
||||
*iter = end;
|
||||
return FALSE;
|
||||
}
|
||||
*iter += length;
|
||||
return TRUE;
|
||||
}
|
||||
|
||||
/* Move *ITER over an leb128, stopping at END. Return true if the end
|
||||
of the leb128 was found. */
|
||||
|
||||
static bfd_boolean
|
||||
skip_leb128 (bfd_byte **iter, bfd_byte *end)
|
||||
{
|
||||
unsigned char byte;
|
||||
do
|
||||
if (!read_byte (iter, end, &byte))
|
||||
return FALSE;
|
||||
while (byte & 0x80);
|
||||
return TRUE;
|
||||
}
|
||||
|
||||
/* Like skip_leb128, but treat the leb128 as an unsigned value and
|
||||
store it in *VALUE. */
|
||||
|
||||
static bfd_boolean
|
||||
read_uleb128 (bfd_byte **iter, bfd_byte *end, bfd_vma *value)
|
||||
{
|
||||
bfd_byte *start, *p;
|
||||
|
||||
start = *iter;
|
||||
if (!skip_leb128 (iter, end))
|
||||
return FALSE;
|
||||
|
||||
p = *iter;
|
||||
*value = *--p;
|
||||
while (p > start)
|
||||
*value = (*value << 7) | (*--p & 0x7f);
|
||||
|
||||
return TRUE;
|
||||
}
|
||||
|
||||
/* Like read_uleb128, but for signed values. */
|
||||
|
||||
static bfd_boolean
|
||||
read_sleb128 (bfd_byte **iter, bfd_byte *end, bfd_signed_vma *value)
|
||||
{
|
||||
bfd_byte *start, *p;
|
||||
|
||||
start = *iter;
|
||||
if (!skip_leb128 (iter, end))
|
||||
return FALSE;
|
||||
|
||||
p = *iter;
|
||||
*value = ((*--p & 0x7f) ^ 0x40) - 0x40;
|
||||
while (p > start)
|
||||
*value = (*value << 7) | (*--p & 0x7f);
|
||||
|
||||
return TRUE;
|
||||
}
|
||||
|
||||
/* Return 0 if either encoding is variable width, or not yet known to bfd. */
|
||||
|
||||
|
|
@ -221,7 +285,6 @@ _bfd_elf_discard_section_eh_frame
|
|||
struct elf_link_hash_table *htab;
|
||||
struct eh_frame_hdr_info *hdr_info;
|
||||
struct eh_frame_sec_info *sec_info = NULL;
|
||||
unsigned int leb128_tmp;
|
||||
unsigned int cie_usage_count, offset;
|
||||
unsigned int ptr_size;
|
||||
|
||||
|
|
@ -293,6 +356,8 @@ _bfd_elf_discard_section_eh_frame
|
|||
for (;;)
|
||||
{
|
||||
unsigned char *aug;
|
||||
bfd_byte *start, *end;
|
||||
bfd_size_type length;
|
||||
|
||||
if (sec_info->count == sec_info->alloced)
|
||||
{
|
||||
|
|
@ -318,19 +383,22 @@ _bfd_elf_discard_section_eh_frame
|
|||
/* If we are at the end of the section, we still need to decide
|
||||
on whether to output or discard last encountered CIE (if any). */
|
||||
if ((bfd_size_type) (buf - ehbuf) == sec->size)
|
||||
hdr.id = (unsigned int) -1;
|
||||
{
|
||||
hdr.id = (unsigned int) -1;
|
||||
end = buf;
|
||||
}
|
||||
else
|
||||
{
|
||||
/* Read the length of the entry. */
|
||||
REQUIRE ((bfd_size_type) (buf - ehbuf) + 4 <= sec->size);
|
||||
hdr.length = bfd_get_32 (abfd, buf);
|
||||
buf += 4;
|
||||
REQUIRE (skip_bytes (&buf, ehbuf + sec->size, 4));
|
||||
hdr.length = bfd_get_32 (abfd, buf - 4);
|
||||
|
||||
/* 64-bit .eh_frame is not supported. */
|
||||
REQUIRE (hdr.length != 0xffffffff);
|
||||
|
||||
/* The CIE/FDE must be fully contained in this input section. */
|
||||
REQUIRE ((bfd_size_type) (buf - ehbuf) + hdr.length <= sec->size);
|
||||
end = buf + hdr.length;
|
||||
|
||||
this_inf->offset = last_fde - ehbuf;
|
||||
this_inf->size = 4 + hdr.length;
|
||||
|
|
@ -348,8 +416,8 @@ _bfd_elf_discard_section_eh_frame
|
|||
}
|
||||
else
|
||||
{
|
||||
hdr.id = bfd_get_32 (abfd, buf);
|
||||
buf += 4;
|
||||
REQUIRE (skip_bytes (&buf, end, 4));
|
||||
hdr.id = bfd_get_32 (abfd, buf - 4);
|
||||
REQUIRE (hdr.id != (unsigned int) -1);
|
||||
}
|
||||
}
|
||||
|
|
@ -392,7 +460,7 @@ _bfd_elf_discard_section_eh_frame
|
|||
cie_usage_count = 0;
|
||||
memset (&cie, 0, sizeof (cie));
|
||||
cie.hdr = hdr;
|
||||
cie.version = *buf++;
|
||||
REQUIRE (read_byte (&buf, end, &cie.version));
|
||||
|
||||
/* Cannot handle unknown versions. */
|
||||
REQUIRE (cie.version == 1 || cie.version == 3);
|
||||
|
|
@ -407,15 +475,18 @@ _bfd_elf_discard_section_eh_frame
|
|||
/* We cannot merge "eh" CIEs because __EXCEPTION_TABLE__
|
||||
is private to each CIE, so we don't need it for anything.
|
||||
Just skip it. */
|
||||
buf += ptr_size;
|
||||
REQUIRE (skip_bytes (&buf, end, ptr_size));
|
||||
SKIP_RELOCS (buf);
|
||||
}
|
||||
read_uleb128 (cie.code_align, buf);
|
||||
read_sleb128 (cie.data_align, buf);
|
||||
REQUIRE (read_uleb128 (&buf, end, &cie.code_align));
|
||||
REQUIRE (read_sleb128 (&buf, end, &cie.data_align));
|
||||
if (cie.version == 1)
|
||||
cie.ra_column = *buf++;
|
||||
{
|
||||
REQUIRE (buf < end);
|
||||
cie.ra_column = *buf++;
|
||||
}
|
||||
else
|
||||
read_uleb128 (cie.ra_column, buf);
|
||||
REQUIRE (read_uleb128 (&buf, end, &cie.ra_column));
|
||||
ENSURE_NO_RELOCS (buf);
|
||||
cie.lsda_encoding = DW_EH_PE_omit;
|
||||
cie.fde_encoding = DW_EH_PE_omit;
|
||||
|
|
@ -426,7 +497,7 @@ _bfd_elf_discard_section_eh_frame
|
|||
if (*aug == 'z')
|
||||
{
|
||||
aug++;
|
||||
read_uleb128 (cie.augmentation_size, buf);
|
||||
REQUIRE (read_uleb128 (&buf, end, &cie.augmentation_size));
|
||||
ENSURE_NO_RELOCS (buf);
|
||||
}
|
||||
|
||||
|
|
@ -434,12 +505,12 @@ _bfd_elf_discard_section_eh_frame
|
|||
switch (*aug++)
|
||||
{
|
||||
case 'L':
|
||||
cie.lsda_encoding = *buf++;
|
||||
REQUIRE (read_byte (&buf, end, &cie.lsda_encoding));
|
||||
ENSURE_NO_RELOCS (buf);
|
||||
REQUIRE (get_DW_EH_PE_width (cie.lsda_encoding, ptr_size));
|
||||
break;
|
||||
case 'R':
|
||||
cie.fde_encoding = *buf++;
|
||||
REQUIRE (read_byte (&buf, end, &cie.fde_encoding));
|
||||
ENSURE_NO_RELOCS (buf);
|
||||
REQUIRE (get_DW_EH_PE_width (cie.fde_encoding, ptr_size));
|
||||
break;
|
||||
|
|
@ -447,14 +518,15 @@ _bfd_elf_discard_section_eh_frame
|
|||
{
|
||||
int per_width;
|
||||
|
||||
cie.per_encoding = *buf++;
|
||||
REQUIRE (read_byte (&buf, end, &cie.per_encoding));
|
||||
per_width = get_DW_EH_PE_width (cie.per_encoding,
|
||||
ptr_size);
|
||||
REQUIRE (per_width);
|
||||
if ((cie.per_encoding & 0xf0) == DW_EH_PE_aligned)
|
||||
buf = (ehbuf
|
||||
+ ((buf - ehbuf + per_width - 1)
|
||||
& ~((bfd_size_type) per_width - 1)));
|
||||
{
|
||||
length = -(buf - ehbuf) & (per_width - 1);
|
||||
REQUIRE (skip_bytes (&buf, end, length));
|
||||
}
|
||||
ENSURE_NO_RELOCS (buf);
|
||||
/* Ensure we have a reloc here, against
|
||||
a global symbol. */
|
||||
|
|
@ -487,7 +559,7 @@ _bfd_elf_discard_section_eh_frame
|
|||
cookie->rel++;
|
||||
while (GET_RELOC (buf) != NULL);
|
||||
}
|
||||
buf += per_width;
|
||||
REQUIRE (skip_bytes (&buf, end, per_width));
|
||||
}
|
||||
break;
|
||||
default:
|
||||
|
|
@ -569,18 +641,21 @@ _bfd_elf_discard_section_eh_frame
|
|||
cie_usage_count++;
|
||||
hdr_info->fde_count++;
|
||||
}
|
||||
if (cie.lsda_encoding != DW_EH_PE_omit)
|
||||
{
|
||||
unsigned int dummy;
|
||||
/* Skip the initial location and address range. */
|
||||
start = buf;
|
||||
length = get_DW_EH_PE_width (cie.fde_encoding, ptr_size);
|
||||
REQUIRE (skip_bytes (&buf, end, 2 * length));
|
||||
|
||||
/* Skip the augmentation size, if present. */
|
||||
if (cie.augmentation[0] == 'z')
|
||||
REQUIRE (skip_leb128 (&buf, end));
|
||||
|
||||
/* Of the supported augmentation characters above, only 'L'
|
||||
adds augmentation data to the FDE. This code would need to
|
||||
be adjusted if any future augmentations do the same thing. */
|
||||
if (cie.lsda_encoding != DW_EH_PE_omit)
|
||||
this_inf->lsda_offset = buf - start;
|
||||
|
||||
aug = buf;
|
||||
buf += 2 * get_DW_EH_PE_width (cie.fde_encoding, ptr_size);
|
||||
if (cie.augmentation[0] == 'z')
|
||||
read_uleb128 (dummy, buf);
|
||||
/* If some new augmentation data is added before LSDA
|
||||
in FDE augmentation area, this need to be adjusted. */
|
||||
this_inf->lsda_offset = (buf - aug);
|
||||
}
|
||||
buf = last_fde + 4 + hdr.length;
|
||||
SKIP_RELOCS (buf);
|
||||
}
|
||||
|
|
@ -792,7 +867,6 @@ _bfd_elf_write_section_eh_frame (bfd *abfd,
|
|||
struct eh_frame_sec_info *sec_info;
|
||||
struct elf_link_hash_table *htab;
|
||||
struct eh_frame_hdr_info *hdr_info;
|
||||
unsigned int leb128_tmp;
|
||||
unsigned int ptr_size;
|
||||
struct eh_cie_fde *ent;
|
||||
|
||||
|
|
@ -894,7 +968,7 @@ _bfd_elf_write_section_eh_frame (bfd *abfd,
|
|||
{
|
||||
unsigned char *aug;
|
||||
unsigned int action, extra_string, extra_data;
|
||||
unsigned int dummy, per_width, per_encoding;
|
||||
unsigned int per_width, per_encoding;
|
||||
|
||||
/* Need to find 'R' or 'L' augmentation's argument and modify
|
||||
DW_EH_PE_* value. */
|
||||
|
|
@ -908,9 +982,9 @@ _bfd_elf_write_section_eh_frame (bfd *abfd,
|
|||
buf += 9;
|
||||
aug = buf;
|
||||
buf = strchr (buf, '\0') + 1;
|
||||
read_uleb128 (dummy, buf);
|
||||
read_sleb128 (dummy, buf);
|
||||
read_uleb128 (dummy, buf);
|
||||
skip_leb128 (&buf, end);
|
||||
skip_leb128 (&buf, end);
|
||||
skip_leb128 (&buf, end);
|
||||
if (*aug == 'z')
|
||||
{
|
||||
/* The uleb128 will always be a single byte for the kind
|
||||
|
|
@ -923,6 +997,7 @@ _bfd_elf_write_section_eh_frame (bfd *abfd,
|
|||
memmove (buf + extra_string + extra_data, buf, end - buf);
|
||||
memmove (aug + extra_string, aug, buf - aug);
|
||||
buf += extra_string;
|
||||
end += extra_string + extra_data;
|
||||
|
||||
if (ent->add_augmentation_size)
|
||||
{
|
||||
|
|
|
|||
Loading…
Reference in a new issue