From 0c66691b92668caaf51aac05a8c30f85867571db Mon Sep 17 00:00:00 2001 From: Evan Huus Date: Fri, 28 Dec 2012 17:04:23 +0000 Subject: [PATCH] Add a strict allocator that does canaries and various other things, for platforms which don't have Valgrind. Valgrind is still the better choice on platforms which support it. svn path=/trunk/; revision=46828 --- epan/CMakeLists.txt | 1 + epan/wmem/Makefile.common | 2 + epan/wmem/wmem_allocator_strict.c | 180 ++++++++++++++++++++++++++++++ epan/wmem/wmem_allocator_strict.h | 58 ++++++++++ epan/wmem/wmem_core.c | 7 ++ epan/wmem/wmem_core.h | 3 +- 6 files changed, 250 insertions(+), 1 deletion(-) create mode 100644 epan/wmem/wmem_allocator_strict.c create mode 100644 epan/wmem/wmem_allocator_strict.h diff --git a/epan/CMakeLists.txt b/epan/CMakeLists.txt index d816b2103b..854c1aae29 100644 --- a/epan/CMakeLists.txt +++ b/epan/CMakeLists.txt @@ -1355,6 +1355,7 @@ set(WMEM_FILES wmem/wmem_core.c wmem/wmem_allocator_block.c wmem/wmem_allocator_simple.c + wmem/wmem_allocator_strict.c wmem/wmem_scopes.c wmem/wmem_slab.c wmem/wmem_slist.c diff --git a/epan/wmem/Makefile.common b/epan/wmem/Makefile.common index 0e8f719579..ee29d22b1d 100644 --- a/epan/wmem/Makefile.common +++ b/epan/wmem/Makefile.common @@ -27,6 +27,7 @@ LIBWMEM_SRC = \ wmem_core.c \ wmem_allocator_block.c \ wmem_allocator_simple.c \ + wmem_allocator_strict.c \ wmem_scopes.c \ wmem_slab.c \ wmem_slist.c \ @@ -40,6 +41,7 @@ LIBWMEM_INCLUDES = \ wmem_allocator.h \ wmem_allocator_block.h \ wmem_allocator_simple.h \ + wmem_allocator_strict.h \ wmem_scopes.h \ wmem_slab.h \ wmem_slist.h \ diff --git a/epan/wmem/wmem_allocator_strict.c b/epan/wmem/wmem_allocator_strict.c new file mode 100644 index 0000000000..dff214d412 --- /dev/null +++ b/epan/wmem/wmem_allocator_strict.c @@ -0,0 +1,180 @@ +/* wmem_allocator_strict.c + * Wireshark Memory Manager Strict Allocator + * Copyright 2012, Evan Huus + * + * $Id$ + * + * Wireshark - Network traffic analyzer + * By Gerald Combs + * Copyright 1998 Gerald Combs + * + * 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 2 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, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include + +#include + +#include "wmem_core.h" +#include "wmem_allocator.h" + +/* In this allocator, we do everything we can to catch invalid memory accesses. + * This includes using canaries (what Valgrind calls redzones) and + * filling allocated and freed memory with garbage. Valgrind is still the + * better tool on the platforms where it is available - use it instead if + * possible. + */ + +#define WMEM_CANARY_SIZE 16 +#define WMEM_CANARY_VALUE 0x8E + +#define WMEM_PREFILL 0xA1 +#define WMEM_POSTFILL 0x1A + +typedef struct _wmem_strict_allocator_block_t { + /* Simple manual singly-linked list of allocations */ + struct _wmem_strict_allocator_block_t *next; + + /* Just the length of real_data, not counting the canaries */ + gsize data_len; + + guint8 *leading_canary; + guint8 *real_data; + guint8 *trailing_canary; +} wmem_strict_allocator_block_t; + +typedef struct _wmem_strict_allocator_t { + wmem_strict_allocator_block_t *block_list; +} wmem_strict_allocator_t; + +static void * +wmem_strict_alloc(void *private_data, const size_t size) +{ + wmem_strict_allocator_t *allocator; + wmem_strict_allocator_block_t *block; + + allocator = (wmem_strict_allocator_t*) private_data; + + block = g_new(wmem_strict_allocator_block_t, 1); + + block->data_len = size; + block->leading_canary = g_malloc(block->data_len + (2 * WMEM_CANARY_SIZE)); + block->real_data = block->leading_canary + WMEM_CANARY_SIZE; + block->trailing_canary = block->real_data + block->data_len; + block->next = allocator->block_list; + allocator->block_list = block; + + memset(block->leading_canary, WMEM_CANARY_VALUE, WMEM_CANARY_SIZE); + memset(block->real_data, WMEM_PREFILL, block->data_len); + memset(block->trailing_canary, WMEM_CANARY_VALUE, WMEM_CANARY_SIZE); + + return block->real_data; +} + +static void +wmem_strict_real_check_canaries(wmem_strict_allocator_t *allocator) +{ + guint i; + wmem_strict_allocator_block_t *block; + + block = allocator->block_list; + + while (block) { + for (i=0; ileading_canary[i] == WMEM_CANARY_VALUE); + g_assert(block->trailing_canary[i] == WMEM_CANARY_VALUE); + } + block = block->next; + } +} + +void +wmem_strict_check_canaries(wmem_allocator_t *allocator) +{ + /* XXX: Should this be a g_assert() instead? This is more of a general API + * issue - should allocator-specific functions be safe to call with an + * allocator of the wrong type or not? And how should they interact with the + * WIRESHARK_DEBUG_WMEM_OVERRIDE environment variable? */ + if (allocator->type != WMEM_ALLOCATOR_STRICT) { + return; + } + + wmem_strict_real_check_canaries(allocator->private_data); +} + +static void +wmem_strict_free_all(void *private_data) +{ + wmem_strict_allocator_t *allocator; + wmem_strict_allocator_block_t *block, *tmp; + + allocator = (wmem_strict_allocator_t*) private_data; + + wmem_strict_real_check_canaries(allocator); + + block = allocator->block_list; + + while (block) { + memset(block->real_data, WMEM_POSTFILL, block->data_len); + + g_free(block->leading_canary); + + tmp = block; + block = block->next; + g_free(tmp); + } + + allocator->block_list = NULL; +} + +static void +wmem_strict_allocator_destroy(wmem_allocator_t *allocator) +{ + g_free(allocator->private_data); + g_free(allocator); +} + +wmem_allocator_t * +wmem_strict_allocator_new(void) +{ + wmem_allocator_t *allocator; + wmem_strict_allocator_t *strict_allocator; + + allocator = g_new(wmem_allocator_t, 1); + strict_allocator = g_new(wmem_strict_allocator_t, 1); + + allocator->alloc = &wmem_strict_alloc; + allocator->free_all = &wmem_strict_free_all; + allocator->destroy = &wmem_strict_allocator_destroy; + allocator->private_data = (void*) strict_allocator; + + strict_allocator->block_list = NULL; + + return allocator; +} + + +/* + * Editor modelines - http://www.wireshark.org/tools/modelines.html + * + * Local variables: + * c-basic-offset: 4 + * tab-width: 8 + * indent-tabs-mode: nil + * End: + * + * vi: set shiftwidth=4 tabstop=8 expandtab: + * :indentSize=4:tabSize=8:noTabs=true: + */ diff --git a/epan/wmem/wmem_allocator_strict.h b/epan/wmem/wmem_allocator_strict.h new file mode 100644 index 0000000000..c4eb1e4269 --- /dev/null +++ b/epan/wmem/wmem_allocator_strict.h @@ -0,0 +1,58 @@ +/* wmem_allocator_strict.h + * Definitions for the Wireshark Memory Manager Strict Allocator + * Copyright 2012, Evan Huus + * + * $Id$ + * + * Wireshark - Network traffic analyzer + * By Gerald Combs + * Copyright 1998 Gerald Combs + * + * 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 2 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, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#ifndef __WMEM_ALLOCATOR_STRICT_H__ +#define __WMEM_ALLOCATOR_STRICT_H__ + +#include "wmem_core.h" + +#ifdef __cplusplus +extern "C" { +#endif /* __cplusplus */ + +wmem_allocator_t * +wmem_strict_allocator_new(void); + +void +wmem_strict_check_canaries(wmem_allocator_t *allocator); + +#ifdef __cplusplus +} +#endif /* __cplusplus */ + +#endif /* __WMEM_ALLOCATOR_STRICT_H__ */ + +/* + * Editor modelines - http://www.wireshark.org/tools/modelines.html + * + * Local variables: + * c-basic-offset: 4 + * tab-width: 8 + * indent-tabs-mode: nil + * End: + * + * vi: set shiftwidth=4 tabstop=8 expandtab: + * :indentSize=4:tabSize=8:noTabs=true: + */ diff --git a/epan/wmem/wmem_core.c b/epan/wmem/wmem_core.c index 5a05332c56..0311ce0a6d 100644 --- a/epan/wmem/wmem_core.c +++ b/epan/wmem/wmem_core.c @@ -32,6 +32,7 @@ #include "wmem_allocator.h" #include "wmem_allocator_simple.h" #include "wmem_allocator_block.h" +#include "wmem_allocator_strict.h" void * wmem_alloc(wmem_allocator_t *allocator, const size_t size) @@ -84,6 +85,9 @@ wmem_allocator_new(const wmem_allocator_type_t type) else if (strncmp(override, "block", strlen("block")) == 0) { real_type = WMEM_ALLOCATOR_BLOCK; } + else if (strncmp(override, "strict", strlen("strict")) == 0) { + real_type = WMEM_ALLOCATOR_STRICT; + } else { g_warning("Unrecognized wmem override"); real_type = type; @@ -96,6 +100,9 @@ wmem_allocator_new(const wmem_allocator_type_t type) case WMEM_ALLOCATOR_BLOCK: allocator = wmem_block_allocator_new(); break; + case WMEM_ALLOCATOR_STRICT: + allocator = wmem_strict_allocator_new(); + break; default: g_assert_not_reached(); /* This is necessary to squelch MSVC errors; is there diff --git a/epan/wmem/wmem_core.h b/epan/wmem/wmem_core.h index a405b269ad..ad71591252 100644 --- a/epan/wmem/wmem_core.h +++ b/epan/wmem/wmem_core.h @@ -34,7 +34,8 @@ extern "C" { typedef enum _wmem_allocator_type_t { WMEM_ALLOCATOR_SIMPLE, - WMEM_ALLOCATOR_BLOCK + WMEM_ALLOCATOR_BLOCK, + WMEM_ALLOCATOR_STRICT } wmem_allocator_type_t; struct _wmem_allocator_t;