readelf: Return correct readp (or readendp) from print_form_data.

print_form_data returns the new readp (or readendp on error) to show how
much data was consumed. But when reading the .debug_str_offsets section
we would reuse readp and readendp. This meant the wrong readp would be
returned to the caller.

Signed-off-by: Mark Wielaard <mark@klomp.org>

diff --git a/src/ChangeLog b/src/ChangeLog
index 6484b9a..fd45405 100644 (file)
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2018-06-11  Mark Wielaard  <mark@klomp.org>
+
+       * readelf.c (print_form_data): Don't reuse readp and readendp when
+       reading str_offsets section.
+
 2018-06-10  Mark Wielaard  <mark@klomp.org>
 
        * readelf.c (print_form_data): Don't cast value to ptrdiff_t, cast

diff --git a/src/readelf.c b/src/readelf.c
index fbda6c1..f185897 100644 (file)
--- a/src/readelf.c
+++ b/src/readelf.c
@@ -7986,17 +7986,17 @@ print_form_data (Dwarf *dbg, int form, const unsigned char *readp,
        str = "???";
       else
        {
-         readp = data->d_buf + str_offsets_base + val;
-         readendp = data->d_buf + data->d_size;
-         if ((size_t) (readendp - readp) < offset_len)
+         const unsigned char *strreadp = data->d_buf + str_offsets_base + val;
+         const unsigned char *strreadendp = data->d_buf + data->d_size;
+         if ((size_t) (strreadendp - strreadp) < offset_len)
            str = "???";
          else
            {
              Dwarf_Off idx;
              if (offset_len == 8)
-               idx = read_8ubyte_unaligned_inc (dbg, readp);
+               idx = read_8ubyte_unaligned_inc (dbg, strreadp);
              else
-               idx = read_4ubyte_unaligned_inc (dbg, readp);
+               idx = read_4ubyte_unaligned_inc (dbg, strreadp);
 
              data = dbg->sectiondata[IDX_debug_str];
              if (data == NULL || idx >= data->d_size