From 424646edf42425390c0174f344a2acbd33b68fc9 Mon Sep 17 00:00:00 2001 From: Andrew Burgess Date: Fri, 7 Jul 2023 17:18:46 +0100 Subject: [PATCH] gdbserver: handle all eval_result_type values in tracepoint.cc It was pointed out[1] that after this commit: commit 3812b38d8de5804ad3eadd6c7a5d532402ddabab Date: Thu Oct 20 11:14:33 2022 +0100 gdbserver: allow agent expressions to fail with invalid memory access Now that agent expressions might fail with the error expr_eval_invalid_memory_access, we might overflow the eval_result_names array in tracepoint.cc. This is because the eval_result_names array does not include a string for either expr_eval_invalid_goto or expr_eval_invalid_memory_access. I don't know if having expr_eval_invalid_goto missing is also a problem, but it feels like eval_result_names should just include a string for every possible error. I could just add two more strings into the array, but I figure that a more robust solution will be to move all of the error types, and their associated strings, into a new ax-result-types.def file, and to then include this file in both ax.h and tracepoint.cc in order to build the enum eval_result_type and the eval_result_names string array. Doing this means it is impossible to have a missing error string in the future. [1] https://inbox.sourceware.org/gdb-patches/01059f8a-0e59-55b5-f530-190c26df5ba3@palves.net/ Approved-By: Pedro Alves --- gdbserver/ax-result-types.def | 44 +++++++++++++++++++++++++++++++++++ gdbserver/ax.h | 13 +++-------- gdbserver/tracepoint.cc | 11 +++------ 3 files changed, 50 insertions(+), 18 deletions(-) create mode 100644 gdbserver/ax-result-types.def diff --git a/gdbserver/ax-result-types.def b/gdbserver/ax-result-types.def new file mode 100644 index 00000000000..7648b8dc0df --- /dev/null +++ b/gdbserver/ax-result-types.def @@ -0,0 +1,44 @@ +/* Agent expression result types. + + Copyright (C) 2023 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 . */ + +/* The AX_RESULT_TYPE macro is used to define a result type that can be + generated by agent expression evaluation. The first macro argument is + the name of an enum entry, and the second is a string that describes + this result type. */ + +AX_RESULT_TYPE (expr_eval_no_error, + "terror:no error") +AX_RESULT_TYPE (expr_eval_empty_expression, + "terror:empty expression") +AX_RESULT_TYPE (expr_eval_empty_stack, + "terror:empty stack") +AX_RESULT_TYPE (expr_eval_stack_overflow, + "terror:stack overflow") +AX_RESULT_TYPE (expr_eval_stack_underflow, + "terror:stack underflow") +AX_RESULT_TYPE (expr_eval_unhandled_opcode, + "terror:unhandled opcode") +AX_RESULT_TYPE (expr_eval_unrecognized_opcode, + "terror:unrecognized opcode") +AX_RESULT_TYPE (expr_eval_divide_by_zero, + "terror:divide by zero") +AX_RESULT_TYPE (expr_eval_invalid_goto, + "terror:invalid goto") +AX_RESULT_TYPE (expr_eval_invalid_memory_access, + "terror:invalid memory access") diff --git a/gdbserver/ax.h b/gdbserver/ax.h index c98e36a83c6..60e307ca42d 100644 --- a/gdbserver/ax.h +++ b/gdbserver/ax.h @@ -33,16 +33,9 @@ struct traceframe; enum eval_result_type { - expr_eval_no_error, - expr_eval_empty_expression, - expr_eval_empty_stack, - expr_eval_stack_overflow, - expr_eval_stack_underflow, - expr_eval_unhandled_opcode, - expr_eval_unrecognized_opcode, - expr_eval_divide_by_zero, - expr_eval_invalid_goto, - expr_eval_invalid_memory_access +#define AX_RESULT_TYPE(ENUM,STR) ENUM, +#include "ax-result-types.def" +#undef AX_RESULT_TYPE }; struct agent_expr diff --git a/gdbserver/tracepoint.cc b/gdbserver/tracepoint.cc index 1f31e0cc05f..609d49a87ef 100644 --- a/gdbserver/tracepoint.cc +++ b/gdbserver/tracepoint.cc @@ -859,14 +859,9 @@ static struct tracepoint *last_tracepoint; static const char * const eval_result_names[] = { - "terror:in the attic", /* this should never be reported */ - "terror:empty expression", - "terror:empty stack", - "terror:stack overflow", - "terror:stack underflow", - "terror:unhandled opcode", - "terror:unrecognized opcode", - "terror:divide by zero" +#define AX_RESULT_TYPE(ENUM,STR) STR, +#include "ax-result-types.def" +#undef AX_RESULT_TYPE }; #endif -- 2.30.2