libbacktrace: use correct directory/filename for DWARF 5

PR debug/98716
	* dwarf.c (read_v2_paths): Allocate zero entry for dirs and
	filenames.
	(read_line_program): Remove parameter u, change caller.  Don't
	subtract one from dirs and filenames index.
	(read_function_entry): Don't subtract one from filenames index.
This commit is contained in:
Ian Lance Taylor
2021-01-18 14:38:10 -08:00
parent 5496ee0a1a
commit 096650403a

64
dwarf.c
View File

@@ -2677,19 +2677,20 @@ read_v2_paths (struct backtrace_state *state, struct unit *u,
++hdr->dirs_count;
}
hdr->dirs = NULL;
if (hdr->dirs_count != 0)
{
hdr->dirs = ((const char **)
backtrace_alloc (state,
hdr->dirs_count * sizeof (const char *),
hdr_buf->error_callback,
hdr_buf->data));
if (hdr->dirs == NULL)
return 0;
}
/* The index of the first entry in the list of directories is 1. Index 0 is
used for the current directory of the compilation. To simplify index
handling, we set entry 0 to the compilation unit directory. */
++hdr->dirs_count;
hdr->dirs = ((const char **)
backtrace_alloc (state,
hdr->dirs_count * sizeof (const char *),
hdr_buf->error_callback,
hdr_buf->data));
if (hdr->dirs == NULL)
return 0;
i = 0;
hdr->dirs[0] = u->comp_dir;
i = 1;
while (*hdr_buf->buf != '\0')
{
if (hdr_buf->reported_underflow)
@@ -2716,6 +2717,10 @@ read_v2_paths (struct backtrace_state *state, struct unit *u,
++hdr->filenames_count;
}
/* The index of the first entry in the list of file names is 1. Index 0 is
used for the DW_AT_name of the compilation unit. To simplify index
handling, we set entry 0 to the compilation unit file name. */
++hdr->filenames_count;
hdr->filenames = ((const char **)
backtrace_alloc (state,
hdr->filenames_count * sizeof (char *),
@@ -2723,7 +2728,8 @@ read_v2_paths (struct backtrace_state *state, struct unit *u,
hdr_buf->data));
if (hdr->filenames == NULL)
return 0;
i = 0;
hdr->filenames[0] = u->filename;
i = 1;
while (*hdr_buf->buf != '\0')
{
const char *filename;
@@ -2737,7 +2743,7 @@ read_v2_paths (struct backtrace_state *state, struct unit *u,
return 0;
dir_index = read_uleb128 (hdr_buf);
if (IS_ABSOLUTE_PATH (filename)
|| (dir_index == 0 && u->comp_dir == NULL))
|| (dir_index < hdr->dirs_count && hdr->dirs[dir_index] == NULL))
hdr->filenames[i] = filename;
else
{
@@ -2746,10 +2752,8 @@ read_v2_paths (struct backtrace_state *state, struct unit *u,
size_t filename_len;
char *s;
if (dir_index == 0)
dir = u->comp_dir;
else if (dir_index - 1 < hdr->dirs_count)
dir = hdr->dirs[dir_index - 1];
if (dir_index < hdr->dirs_count)
dir = hdr->dirs[dir_index];
else
{
dwarf_buf_error (hdr_buf,
@@ -3037,8 +3041,8 @@ read_line_header (struct backtrace_state *state, struct dwarf_data *ddata,
static int
read_line_program (struct backtrace_state *state, struct dwarf_data *ddata,
struct unit *u, const struct line_header *hdr,
struct dwarf_buf *line_buf, struct line_vector *vec)
const struct line_header *hdr, struct dwarf_buf *line_buf,
struct line_vector *vec)
{
uint64_t address;
unsigned int op_index;
@@ -3048,8 +3052,8 @@ read_line_program (struct backtrace_state *state, struct dwarf_data *ddata,
address = 0;
op_index = 0;
if (hdr->filenames_count > 0)
reset_filename = hdr->filenames[0];
if (hdr->filenames_count > 1)
reset_filename = hdr->filenames[1];
else
reset_filename = "";
filename = reset_filename;
@@ -3114,10 +3118,8 @@ read_line_program (struct backtrace_state *state, struct dwarf_data *ddata,
size_t f_len;
char *p;
if (dir_index == 0 && hdr->version < 5)
dir = u->comp_dir;
else if (dir_index - 1 < hdr->dirs_count)
dir = hdr->dirs[dir_index - 1];
if (dir_index < hdr->dirs_count)
dir = hdr->dirs[dir_index];
else
{
dwarf_buf_error (line_buf,
@@ -3184,14 +3186,14 @@ read_line_program (struct backtrace_state *state, struct dwarf_data *ddata,
filename = "";
else
{
if (fileno - 1 >= hdr->filenames_count)
if (fileno >= hdr->filenames_count)
{
dwarf_buf_error (line_buf,
("invalid file number in "
"line number program"));
return 0;
}
filename = hdr->filenames[fileno - 1];
filename = hdr->filenames[fileno];
}
}
break;
@@ -3281,7 +3283,7 @@ read_line_info (struct backtrace_state *state, struct dwarf_data *ddata,
if (!read_line_header (state, ddata, u, is_dwarf64, &line_buf, hdr))
goto fail;
if (!read_line_program (state, ddata, u, hdr, &line_buf, &vec))
if (!read_line_program (state, ddata, hdr, &line_buf, &vec))
goto fail;
if (line_buf.reported_underflow)
@@ -3622,7 +3624,7 @@ read_function_entry (struct backtrace_state *state, struct dwarf_data *ddata,
function->caller_filename = "";
else
{
if (val.u.uint - 1 >= lhdr->filenames_count)
if (val.u.uint >= lhdr->filenames_count)
{
dwarf_buf_error (unit_buf,
("invalid file number in "
@@ -3630,7 +3632,7 @@ read_function_entry (struct backtrace_state *state, struct dwarf_data *ddata,
return 0;
}
function->caller_filename =
lhdr->filenames[val.u.uint - 1];
lhdr->filenames[val.u.uint];
}
}
break;