binutils-gdb/gdb/gdbserver/nto-x86-low.c
Joel Brobecker 190852c8ac gdbserver/Windows: crash during connection establishment phase
On Windows, starting a new process with GDBserver seems to work,
in the sense that the program does get started, and GDBserver
confirms that it is listening for GDB to connect. However, as soon as
GDB establishes the connection with GDBserver, and starts discussing
with it, GDBserver crashes, with a SEGV.

This SEGV occurs in remote-utils.c::prepare_resume_reply...

  | regp = current_target_desc ()->expedite_regs;
  | [...]
  | while (*regp)

... because, in our case, REGP is NULL.

This patches fixes the issues by adding a parameter to init_target_desc,
in order to make sure that we always provide the list of registers when
we initialize a target description.

gdb/ChangeLog:

        PR server/23158:
        * regformats/regdat.sh: Adjust script, following the addition
        of the new expedite_regs parameter to init_target_desc.

gdb/gdbserver/ChangeLog:

        PR server/23158:
        * tdesc.h (init_target_desc) <expedite_regs>: New parameter.
        * tdesc.c (init_target_desc) <expedite_regs>: New parameter.
        Use it to set the expedite_regs field in the given tdesc.
        * x86-tdesc.h: New file.
        * linux-aarch64-tdesc.c (aarch64_linux_read_description):
        Adjust following the addition of the new expedite_regs parameter
        to init_target_desc.
        * linux-tic6x-low.c (tic6x_read_description): Likewise.
        * linux-x86-tdesc.c: #include "x86-tdesc.h".
        (i386_linux_read_description, amd64_linux_read_description):
        Adjust following the addition of the new expedite_regs parameter
        to init_target_desc.
        * lynx-i386-low.c: #include "x86-tdesc.h".
        (lynx_i386_arch_setup): Adjust following the addition of the new
        expedite_regs parameter to init_target_desc.
        * nto-x86-low.c: #include "x86-tdesc.h".
        (nto_x86_arch_setup): Adjust following the addition of the new
        expedite_regs parameter to init_target_desc.
        * win32-i386-low.c: #include "x86-tdesc.h".
        (i386_arch_setup): Adjust following the addition of the new
        expedite_regs parameter to init_target_desc.
2018-05-10 11:27:13 -04:00

110 lines
2.5 KiB
C

/* QNX Neutrino specific low level interface, for the remote server
for GDB.
Copyright (C) 2009-2018 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "server.h"
#include "nto-low.h"
#include "regdef.h"
#include "regcache.h"
#include <x86/context.h>
#include "x86-xstate.h"
#include "arch/i386.h"
#include "x86-tdesc.h"
const unsigned char x86_breakpoint[] = { 0xCC };
#define x86_breakpoint_len 1
/* Returns offset in appropriate Neutrino's context structure.
Defined in x86/context.h.
GDBREGNO is index into regs_i386 array. It is autogenerated and
hopefully doesn't change. */
static int
nto_x86_register_offset (int gdbregno)
{
if (gdbregno >= 0 && gdbregno < 16)
{
X86_CPU_REGISTERS *dummy = (void*)0;
/* GPRs */
switch (gdbregno)
{
case 0:
return (int)&(dummy->eax);
case 1:
return (int)&(dummy->ecx);
case 2:
return (int)&(dummy->edx);
case 3:
return (int)&(dummy->ebx);
case 4:
return (int)&(dummy->esp);
case 5:
return (int)&(dummy->ebp);
case 6:
return (int)&(dummy->esi);
case 7:
return (int)&(dummy->edi);
case 8:
return (int)&(dummy->eip);
case 9:
return (int)&(dummy->efl);
case 10:
return (int)&(dummy->cs);
case 11:
return (int)&(dummy->ss);
#ifdef __SEGMENTS__
case 12:
return (int)&(dummy->ds);
case 13:
return (int)&(dummy->es);
case 14:
return (int)&(dummy->fs);
case 15:
return (int)&(dummy->gs);
#endif
default:
return -1;
}
}
return -1;
}
static void
nto_x86_arch_setup (void)
{
the_low_target.num_regs = 16;
struct target_desc *tdesc
= i386_create_target_description (X86_XSTATE_SSE_MASK, false);
init_target_desc (tdesc, i386_expedite_regs);
nto_tdesc = tdesc;
}
struct nto_target_ops the_low_target =
{
nto_x86_arch_setup,
0, /* num_regs */
nto_x86_register_offset,
x86_breakpoint,
x86_breakpoint_len
};