[PING] [PATCH v2] Rebase executable to match relocated base address

["Hannes Domani via gdb-patches" <gdb-patches@sourceware.org>]

Ping.

Am Donnerstag, 13. Februar 2020, 19:14:51 MEZ hat Hannes Domani <ssbssa@yahoo.de> Folgendes geschrieben:

> Windows executables linked with -dynamicbase get a new base address
> when loaded, which makes debugging impossible if the executable isn't
> also rebased in gdb.
>
> The new base address is read from the Process Environment Block.
> ---
> v2:
> This version now no longer needs the fake auxv entry.
> ---
> gdb/windows-tdep.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 49 insertions(+)
>
> diff --git a/gdb/windows-tdep.c b/gdb/windows-tdep.c
> index 6eef3fbd96..29c0a828a7 100644
> --- a/gdb/windows-tdep.c
> +++ b/gdb/windows-tdep.c
> @@ -34,6 +34,9 @@
> #include "solib.h"
> #include "solib-target.h"
> #include "gdbcore.h"
> +#include "coff/internal.h"
> +#include "libcoff.h"
> +#include "solist.h"
>
> /* Windows signal numbers differ between MinGW flavors and between
>     those and Cygwin.  The below enumeration was gleaned from the
> @@ -812,6 +815,50 @@ windows_get_siginfo_type (struct gdbarch *gdbarch)
>   return siginfo_type;
> }
>
> +/* Implement the "solib_create_inferior_hook" target_so_ops method.  */
> +
> +static void
> +windows_solib_create_inferior_hook (int from_tty)
> +{
> +  CORE_ADDR exec_base = 0;
> +
> +  /* Find base address of main executable in
> +    TIB->process_environment_block->image_base_address.  */
> +  struct gdbarch *gdbarch = target_gdbarch ();
> +  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
> +  int ptr_bytes;
> +  int peb_offset;  /* Offset of process_environment_block in TIB.  */
> +  int base_offset; /* Offset of image_base_address in PEB.  */
> +  if (gdbarch_ptr_bit (gdbarch) == 32)
> +    {
> +      ptr_bytes = 4;
> +      peb_offset = 48;
> +      base_offset = 8;
> +    }
> +  else
> +    {
> +      ptr_bytes = 8;
> +      peb_offset = 96;
> +      base_offset = 16;
> +    }
> +  CORE_ADDR tlb;
> +  gdb_byte buf[8];
> +  if (target_get_tib_address (inferior_ptid, &tlb)
> +      && !target_read_memory (tlb + peb_offset, buf, ptr_bytes))
> +    {
> +      CORE_ADDR peb = extract_unsigned_integer (buf, ptr_bytes, byte_order);
> +      if (!target_read_memory (peb + base_offset, buf, ptr_bytes))
> +    exec_base = extract_unsigned_integer (buf, ptr_bytes, byte_order);
> +    }
> +
> +  if (symfile_objfile && exec_base)
> +    {
> +      CORE_ADDR vmaddr = pe_data (exec_bfd)->pe_opthdr.ImageBase;
> +      if (vmaddr != exec_base)
> +    objfile_rebase (symfile_objfile, exec_base - vmaddr);
> +    }
> +}
> +
> /* To be called from the various GDB_OSABI_CYGWIN handlers for the
>     various Windows architectures and machine types.  */
>
> @@ -830,6 +877,8 @@ windows_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
>
>   set_gdbarch_gdb_signal_to_target (gdbarch, windows_gdb_signal_to_target);
>
> +  solib_target_so_ops.solib_create_inferior_hook
> +    = windows_solib_create_inferior_hook;
>   set_solib_ops (gdbarch, &solib_target_so_ops);
>
>   set_gdbarch_get_siginfo_type (gdbarch, windows_get_siginfo_type);
> --
> 2.25.0