diff options
Diffstat (limited to 'lib/bcheck.c')
| -rw-r--r-- | lib/bcheck.c | 979 |
1 files changed, 979 insertions, 0 deletions
diff --git a/lib/bcheck.c b/lib/bcheck.c new file mode 100644 index 0000000..90f0ad2 --- /dev/null +++ b/lib/bcheck.c @@ -0,0 +1,979 @@ +/* + * Tiny C Memory and bounds checker + * + * Copyright (c) 2002 Fabrice Bellard + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ +#include <stdlib.h> +#include <stdio.h> +#include <stdarg.h> +#include <string.h> + +#if !defined(__FreeBSD__) \ + && !defined(__FreeBSD_kernel__) \ + && !defined(__DragonFly__) \ + && !defined(__OpenBSD__) \ + && !defined(__NetBSD__) +#include <malloc.h> +#endif + +#if !defined(_WIN32) +#include <unistd.h> +#endif + +/* #define BOUND_DEBUG */ + +#ifdef BOUND_DEBUG + #define dprintf(a...) fprintf(a) +#else + #define dprintf(a...) +#endif + +/* define so that bound array is static (faster, but use memory if + bound checking not used) */ +/* #define BOUND_STATIC */ + +/* use malloc hooks. Currently the code cannot be reliable if no hooks */ +#define CONFIG_TCC_MALLOC_HOOKS +#define HAVE_MEMALIGN + +#if defined(__FreeBSD__) \ + || defined(__FreeBSD_kernel__) \ + || defined(__DragonFly__) \ + || defined(__OpenBSD__) \ + || defined(__NetBSD__) \ + || defined(__dietlibc__) \ + || defined(_WIN32) +//#warning Bound checking does not support malloc (etc.) in this environment. +#undef CONFIG_TCC_MALLOC_HOOKS +#undef HAVE_MEMALIGN +#endif + +#define BOUND_T1_BITS 13 +#define BOUND_T2_BITS 11 +#define BOUND_T3_BITS (sizeof(size_t)*8 - BOUND_T1_BITS - BOUND_T2_BITS) +#define BOUND_E_BITS (sizeof(size_t)) + +#define BOUND_T1_SIZE ((size_t)1 << BOUND_T1_BITS) +#define BOUND_T2_SIZE ((size_t)1 << BOUND_T2_BITS) +#define BOUND_T3_SIZE ((size_t)1 << BOUND_T3_BITS) + +#define BOUND_T23_BITS (BOUND_T2_BITS + BOUND_T3_BITS) +#define BOUND_T23_SIZE ((size_t)1 << BOUND_T23_BITS) + + +/* this pointer is generated when bound check is incorrect */ +#define INVALID_POINTER ((void *)(-2)) +/* size of an empty region */ +#define EMPTY_SIZE ((size_t)(-1)) +/* size of an invalid region */ +#define INVALID_SIZE 0 + +typedef struct BoundEntry { + size_t start; + size_t size; + struct BoundEntry *next; + size_t is_invalid; /* true if pointers outside region are invalid */ +} BoundEntry; + +/* external interface */ +void __bound_init(void); +void __bound_new_region(void *p, size_t size); +int __bound_delete_region(void *p); + +#ifdef __attribute__ + /* an __attribute__ macro is defined in the system headers */ + #undef __attribute__ +#endif +#define FASTCALL __attribute__((regparm(3))) + +void *__bound_malloc(size_t size, const void *caller); +void *__bound_memalign(size_t size, size_t align, const void *caller); +void __bound_free(void *ptr, const void *caller); +void *__bound_realloc(void *ptr, size_t size, const void *caller); +static void *libc_malloc(size_t size); +static void libc_free(void *ptr); +static void install_malloc_hooks(void); +static void restore_malloc_hooks(void); + +#ifdef CONFIG_TCC_MALLOC_HOOKS +static void *saved_malloc_hook; +static void *saved_free_hook; +static void *saved_realloc_hook; +static void *saved_memalign_hook; +#endif + +/* TCC definitions */ +extern char __bounds_start; /* start of static bounds table */ +/* error message, just for TCC */ +const char *__bound_error_msg; + +/* runtime error output */ +extern void rt_error(size_t pc, const char *fmt, ...); + +#ifdef BOUND_STATIC +static BoundEntry *__bound_t1[BOUND_T1_SIZE]; /* page table */ +#else +static BoundEntry **__bound_t1; /* page table */ +#endif +static BoundEntry *__bound_empty_t2; /* empty page, for unused pages */ +static BoundEntry *__bound_invalid_t2; /* invalid page, for invalid pointers */ + +static BoundEntry *__bound_find_region(BoundEntry *e1, void *p) +{ + size_t addr, tmp; + BoundEntry *e; + + e = e1; + while (e != NULL) { + addr = (size_t)p; + addr -= e->start; + if (addr <= e->size) { + /* put region at the head */ + tmp = e1->start; + e1->start = e->start; + e->start = tmp; + tmp = e1->size; + e1->size = e->size; + e->size = tmp; + return e1; + } + e = e->next; + } + /* no entry found: return empty entry or invalid entry */ + if (e1->is_invalid) + return __bound_invalid_t2; + else + return __bound_empty_t2; +} + +/* print a bound error message */ +static void bound_error(const char *fmt, ...) +{ + __bound_error_msg = fmt; + fprintf(stderr,"%s %s: %s\n", __FILE__, __FUNCTION__, fmt); + *(void **)0 = 0; /* force a runtime error */ +} + +static void bound_alloc_error(void) +{ + bound_error("not enough memory for bound checking code"); +} + +/* return '(p + offset)' for pointer arithmetic (a pointer can reach + the end of a region in this case */ +void * FASTCALL __bound_ptr_add(void *p, size_t offset) +{ + size_t addr = (size_t)p; + BoundEntry *e; + + dprintf(stderr, "%s %s: %p %x\n", + __FILE__, __FUNCTION__, p, (unsigned)offset); + + __bound_init(); + + e = __bound_t1[addr >> (BOUND_T2_BITS + BOUND_T3_BITS)]; + e = (BoundEntry *)((char *)e + + ((addr >> (BOUND_T3_BITS - BOUND_E_BITS)) & + ((BOUND_T2_SIZE - 1) << BOUND_E_BITS))); + addr -= e->start; + if (addr > e->size) { + e = __bound_find_region(e, p); + addr = (size_t)p - e->start; + } + addr += offset; + if (addr >= e->size) { + fprintf(stderr,"%s %s: %p is outside of the region\n", + __FILE__, __FUNCTION__, p + offset); + return INVALID_POINTER; /* return an invalid pointer */ + } + return p + offset; +} + +/* return '(p + offset)' for pointer indirection (the resulting must + be strictly inside the region */ +#define BOUND_PTR_INDIR(dsize) \ +void * FASTCALL __bound_ptr_indir ## dsize (void *p, size_t offset) \ +{ \ + size_t addr = (size_t)p; \ + BoundEntry *e; \ + \ + dprintf(stderr, "%s %s: %p %x start\n", \ + __FILE__, __FUNCTION__, p, (unsigned)offset); \ + \ + __bound_init(); \ + e = __bound_t1[addr >> (BOUND_T2_BITS + BOUND_T3_BITS)]; \ + e = (BoundEntry *)((char *)e + \ + ((addr >> (BOUND_T3_BITS - BOUND_E_BITS)) & \ + ((BOUND_T2_SIZE - 1) << BOUND_E_BITS))); \ + addr -= e->start; \ + if (addr > e->size) { \ + e = __bound_find_region(e, p); \ + addr = (size_t)p - e->start; \ + } \ + addr += offset + dsize; \ + if (addr > e->size) { \ + fprintf(stderr,"%s %s: %p is outside of the region\n", \ + __FILE__, __FUNCTION__, p + offset); \ + return INVALID_POINTER; /* return an invalid pointer */ \ + } \ + dprintf(stderr, "%s %s: return p+offset = %p\n", \ + __FILE__, __FUNCTION__, p + offset); \ + return p + offset; \ +} + +BOUND_PTR_INDIR(1) +BOUND_PTR_INDIR(2) +BOUND_PTR_INDIR(4) +BOUND_PTR_INDIR(8) +BOUND_PTR_INDIR(12) +BOUND_PTR_INDIR(16) + +#if defined(__GNUC__) && (__GNUC__ >= 6) +/* + * At least gcc 6.2 complains when __builtin_frame_address is used with + * nonzero argument. + */ +#pragma GCC diagnostic push +#pragma GCC diagnostic ignored "-Wframe-address" +#endif + +/* return the frame pointer of the caller */ +#define GET_CALLER_FP(fp)\ +{\ + fp = (size_t)__builtin_frame_address(1);\ +} + +/* called when entering a function to add all the local regions */ +void FASTCALL __bound_local_new(void *p1) +{ + size_t addr, size, fp, *p = p1; + + dprintf(stderr, "%s, %s start p1=%p\n", __FILE__, __FUNCTION__, p); + GET_CALLER_FP(fp); + for(;;) { + addr = p[0]; + if (addr == 0) + break; + addr += fp; + size = p[1]; + p += 2; + __bound_new_region((void *)addr, size); + } + dprintf(stderr, "%s, %s end\n", __FILE__, __FUNCTION__); +} + +/* called when leaving a function to delete all the local regions */ +void FASTCALL __bound_local_delete(void *p1) +{ + size_t addr, fp, *p = p1; + GET_CALLER_FP(fp); + for(;;) { + addr = p[0]; + if (addr == 0) + break; + addr += fp; + p += 2; + __bound_delete_region((void *)addr); + } +} + +#if defined(__GNUC__) && (__GNUC__ >= 6) +#pragma GCC diagnostic pop +#endif + +static BoundEntry *__bound_new_page(void) +{ + BoundEntry *page; + size_t i; + + page = libc_malloc(sizeof(BoundEntry) * BOUND_T2_SIZE); + if (!page) + bound_alloc_error(); + for(i=0;i<BOUND_T2_SIZE;i++) { + /* put empty entries */ + page[i].start = 0; + page[i].size = EMPTY_SIZE; + page[i].next = NULL; + page[i].is_invalid = 0; + } + return page; +} + +/* currently we use malloc(). Should use bound_new_page() */ +static BoundEntry *bound_new_entry(void) +{ + BoundEntry *e; + e = libc_malloc(sizeof(BoundEntry)); + return e; +} + +static void bound_free_entry(BoundEntry *e) +{ + libc_free(e); +} + +static BoundEntry *get_page(size_t index) +{ + BoundEntry *page; + page = __bound_t1[index]; + if (!page || page == __bound_empty_t2 || page == __bound_invalid_t2) { + /* create a new page if necessary */ + page = __bound_new_page(); + __bound_t1[index] = page; + } + return page; +} + +/* mark a region as being invalid (can only be used during init) */ +static void mark_invalid(size_t addr, size_t size) +{ + size_t start, end; + BoundEntry *page; + size_t t1_start, t1_end, i, j, t2_start, t2_end; + + start = addr; + end = addr + size; + + t2_start = (start + BOUND_T3_SIZE - 1) >> BOUND_T3_BITS; + if (end != 0) + t2_end = end >> BOUND_T3_BITS; + else + t2_end = 1 << (BOUND_T1_BITS + BOUND_T2_BITS); + +#if 0 + dprintf(stderr, "mark_invalid: start = %x %x\n", t2_start, t2_end); +#endif + + /* first we handle full pages */ + t1_start = (t2_start + BOUND_T2_SIZE - 1) >> BOUND_T2_BITS; + t1_end = t2_end >> BOUND_T2_BITS; + + i = t2_start & (BOUND_T2_SIZE - 1); + j = t2_end & (BOUND_T2_SIZE - 1); + + if (t1_start == t1_end) { + page = get_page(t2_start >> BOUND_T2_BITS); + for(; i < j; i++) { + page[i].size = INVALID_SIZE; + page[i].is_invalid = 1; + } + } else { + if (i > 0) { + page = get_page(t2_start >> BOUND_T2_BITS); + for(; i < BOUND_T2_SIZE; i++) { + page[i].size = INVALID_SIZE; + page[i].is_invalid = 1; + } + } + for(i = t1_start; i < t1_end; i++) { + __bound_t1[i] = __bound_invalid_t2; + } + if (j != 0) { + page = get_page(t1_end); + for(i = 0; i < j; i++) { + page[i].size = INVALID_SIZE; + page[i].is_invalid = 1; + } + } + } +} + +void __bound_init(void) +{ + size_t i; + BoundEntry *page; + size_t start, size; + size_t *p; + + static int inited; + if (inited) + return; + + inited = 1; + + dprintf(stderr, "%s, %s() start\n", __FILE__, __FUNCTION__); + + /* save malloc hooks and install bound check hooks */ + install_malloc_hooks(); + +#ifndef BOUND_STATIC + __bound_t1 = libc_malloc(BOUND_T1_SIZE * sizeof(BoundEntry *)); + if (!__bound_t1) + bound_alloc_error(); +#endif + __bound_empty_t2 = __bound_new_page(); + for(i=0;i<BOUND_T1_SIZE;i++) { + __bound_t1[i] = __bound_empty_t2; + } + + page = __bound_new_page(); + for(i=0;i<BOUND_T2_SIZE;i++) { + /* put invalid entries */ + page[i].start = 0; + page[i].size = INVALID_SIZE; + page[i].next = NULL; + page[i].is_invalid = 1; + } + __bound_invalid_t2 = page; + + /* invalid pointer zone */ + start = (size_t)INVALID_POINTER & ~(BOUND_T23_SIZE - 1); + size = BOUND_T23_SIZE; + mark_invalid(start, size); + +#if defined(CONFIG_TCC_MALLOC_HOOKS) + /* malloc zone is also marked invalid. can only use that with + * hooks because all libs should use the same malloc. The solution + * would be to build a new malloc for tcc. + * + * usually heap (= malloc zone) comes right after bss, i.e. after _end, but + * not always - either if we are running from under `tcc -b -run`, or if + * address space randomization is turned on(a), heap start will be separated + * from bss end. + * + * So sbrk(0) will be a good approximation for start_brk: + * + * - if we are a separately compiled program, __bound_init() runs early, + * and sbrk(0) should be equal or very near to start_brk(b) (in case other + * constructors malloc something), or + * + * - if we are running from under `tcc -b -run`, sbrk(0) will return + * start of heap portion which is under this program control, and not + * mark as invalid earlier allocated memory. + * + * + * (a) /proc/sys/kernel/randomize_va_space = 2, on Linux; + * usually turned on by default. + * + * (b) on Linux >= v3.3, the alternative is to read + * start_brk from /proc/self/stat + */ + start = (size_t)sbrk(0); + size = 128 * 0x100000; + mark_invalid(start, size); +#endif + + /* add all static bound check values */ + p = (size_t *)&__bounds_start; + while (p[0] != 0) { + __bound_new_region((void *)p[0], p[1]); + p += 2; + } + + dprintf(stderr, "%s, %s() end\n\n", __FILE__, __FUNCTION__); +} + +void __bound_main_arg(void **p) +{ + void *start = p; + while (*p++); + + dprintf(stderr, "%s, %s calling __bound_new_region(%p %x)\n", + __FILE__, __FUNCTION__, start, (unsigned)((void *)p - start)); + + __bound_new_region(start, (void *) p - start); +} + +void __bound_exit(void) +{ + dprintf(stderr, "%s, %s()\n", __FILE__, __FUNCTION__); + restore_malloc_hooks(); +} + +static inline void add_region(BoundEntry *e, + size_t start, size_t size) +{ + BoundEntry *e1; + if (e->start == 0) { + /* no region : add it */ + e->start = start; + e->size = size; + } else { + /* already regions in the list: add it at the head */ + e1 = bound_new_entry(); + e1->start = e->start; + e1->size = e->size; + e1->next = e->next; + e->start = start; + e->size = size; + e->next = e1; + } +} + +/* create a new region. It should not already exist in the region list */ +void __bound_new_region(void *p, size_t size) +{ + size_t start, end; + BoundEntry *page, *e, *e2; + size_t t1_start, t1_end, i, t2_start, t2_end; + + dprintf(stderr, "%s, %s(%p, %x) start\n", + __FILE__, __FUNCTION__, p, (unsigned)size); + + __bound_init(); + + start = (size_t)p; + end = start + size; + t1_start = start >> (BOUND_T2_BITS + BOUND_T3_BITS); + t1_end = end >> (BOUND_T2_BITS + BOUND_T3_BITS); + + /* start */ + page = get_page(t1_start); + t2_start = (start >> (BOUND_T3_BITS - BOUND_E_BITS)) & + ((BOUND_T2_SIZE - 1) << BOUND_E_BITS); + t2_end = (end >> (BOUND_T3_BITS - BOUND_E_BITS)) & + ((BOUND_T2_SIZE - 1) << BOUND_E_BITS); + + + e = (BoundEntry *)((char *)page + t2_start); + add_region(e, start, size); + + if (t1_end == t1_start) { + /* same ending page */ + e2 = (BoundEntry *)((char *)page + t2_end); + if (e2 > e) { + e++; + for(;e<e2;e++) { + e->start = start; + e->size = size; + } + add_region(e, start, size); + } + } else { + /* mark until end of page */ + e2 = page + BOUND_T2_SIZE; + e++; + for(;e<e2;e++) { + e->start = start; + e->size = size; + } + /* mark intermediate pages, if any */ + for(i=t1_start+1;i<t1_end;i++) { + page = get_page(i); + e2 = page + BOUND_T2_SIZE; + for(e=page;e<e2;e++) { + e->start = start; + e->size = size; + } + } + /* last page */ + page = get_page(t1_end); + e2 = (BoundEntry *)((char *)page + t2_end); + for(e=page;e<e2;e++) { + e->start = start; + e->size = size; + } + add_region(e, start, size); + } + + dprintf(stderr, "%s, %s end\n", __FILE__, __FUNCTION__); +} + +/* delete a region */ +static inline void delete_region(BoundEntry *e, void *p, size_t empty_size) +{ + size_t addr; + BoundEntry *e1; + + addr = (size_t)p; + addr -= e->start; + if (addr <= e->size) { + /* region found is first one */ + e1 = e->next; + if (e1 == NULL) { + /* no more region: mark it empty */ + e->start = 0; + e->size = empty_size; + } else { + /* copy next region in head */ + e->start = e1->start; + e->size = e1->size; + e->next = e1->next; + bound_free_entry(e1); + } + } else { + /* find the matching region */ + for(;;) { + e1 = e; + e = e->next; + /* region not found: do nothing */ + if (e == NULL) + break; + addr = (size_t)p - e->start; + if (addr <= e->size) { + /* found: remove entry */ + e1->next = e->next; + bound_free_entry(e); + break; + } + } + } +} + +/* WARNING: 'p' must be the starting point of the region. */ +/* return non zero if error */ +int __bound_delete_region(void *p) +{ + size_t start, end, addr, size, empty_size; + BoundEntry *page, *e, *e2; + size_t t1_start, t1_end, t2_start, t2_end, i; + + dprintf(stderr, "%s %s() start\n", __FILE__, __FUNCTION__); + + __bound_init(); + + start = (size_t)p; + t1_start = start >> (BOUND_T2_BITS + BOUND_T3_BITS); + t2_start = (start >> (BOUND_T3_BITS - BOUND_E_BITS)) & + ((BOUND_T2_SIZE - 1) << BOUND_E_BITS); + + /* find region size */ + page = __bound_t1[t1_start]; + e = (BoundEntry *)((char *)page + t2_start); + addr = start - e->start; + if (addr > e->size) + e = __bound_find_region(e, p); + /* test if invalid region */ + if (e->size == EMPTY_SIZE || (size_t)p != e->start) + return -1; + /* compute the size we put in invalid regions */ + if (e->is_invalid) + empty_size = INVALID_SIZE; + else + empty_size = EMPTY_SIZE; + size = e->size; + end = start + size; + + /* now we can free each entry */ + t1_end = end >> (BOUND_T2_BITS + BOUND_T3_BITS); + t2_end = (end >> (BOUND_T3_BITS - BOUND_E_BITS)) & + ((BOUND_T2_SIZE - 1) << BOUND_E_BITS); + + delete_region(e, p, empty_size); + if (t1_end == t1_start) { + /* same ending page */ + e2 = (BoundEntry *)((char *)page + t2_end); + if (e2 > e) { + e++; + for(;e<e2;e++) { + e->start = 0; + e->size = empty_size; + } + delete_region(e, p, empty_size); + } + } else { + /* mark until end of page */ + e2 = page + BOUND_T2_SIZE; + e++; + for(;e<e2;e++) { + e->start = 0; + e->size = empty_size; + } + /* mark intermediate pages, if any */ + /* XXX: should free them */ + for(i=t1_start+1;i<t1_end;i++) { + page = get_page(i); + e2 = page + BOUND_T2_SIZE; + for(e=page;e<e2;e++) { + e->start = 0; + e->size = empty_size; + } + } + /* last page */ + page = get_page(t1_end); + e2 = (BoundEntry *)((char *)page + t2_end); + for(e=page;e<e2;e++) { + e->start = 0; + e->size = empty_size; + } + delete_region(e, p, empty_size); + } + + dprintf(stderr, "%s %s() end\n", __FILE__, __FUNCTION__); + + return 0; +} + +/* return the size of the region starting at p, or EMPTY_SIZE if non + existent region. */ +static size_t get_region_size(void *p) +{ + size_t addr = (size_t)p; + BoundEntry *e; + + e = __bound_t1[addr >> (BOUND_T2_BITS + BOUND_T3_BITS)]; + e = (BoundEntry *)((char *)e + + ((addr >> (BOUND_T3_BITS - BOUND_E_BITS)) & + ((BOUND_T2_SIZE - 1) << BOUND_E_BITS))); + addr -= e->start; + if (addr > e->size) + e = __bound_find_region(e, p); + if (e->start != (size_t)p) + return EMPTY_SIZE; + return e->size; +} + +/* patched memory functions */ + +/* force compiler to perform stores coded up to this point */ +#define barrier() __asm__ __volatile__ ("": : : "memory") + +static void install_malloc_hooks(void) +{ +#ifdef CONFIG_TCC_MALLOC_HOOKS + saved_malloc_hook = __malloc_hook; + saved_free_hook = __free_hook; + saved_realloc_hook = __realloc_hook; + saved_memalign_hook = __memalign_hook; + __malloc_hook = __bound_malloc; + __free_hook = __bound_free; + __realloc_hook = __bound_realloc; + __memalign_hook = __bound_memalign; + + barrier(); +#endif +} + +static void restore_malloc_hooks(void) +{ +#ifdef CONFIG_TCC_MALLOC_HOOKS + __malloc_hook = saved_malloc_hook; + __free_hook = saved_free_hook; + __realloc_hook = saved_realloc_hook; + __memalign_hook = saved_memalign_hook; + + barrier(); +#endif +} + +static void *libc_malloc(size_t size) +{ + void *ptr; + restore_malloc_hooks(); + ptr = malloc(size); + install_malloc_hooks(); + return ptr; +} + +static void libc_free(void *ptr) +{ + restore_malloc_hooks(); + free(ptr); + install_malloc_hooks(); +} + +/* XXX: we should use a malloc which ensure that it is unlikely that + two malloc'ed data have the same address if 'free' are made in + between. */ +void *__bound_malloc(size_t size, const void *caller) +{ + void *ptr; + + /* we allocate one more byte to ensure the regions will be + separated by at least one byte. With the glibc malloc, it may + be in fact not necessary */ + ptr = libc_malloc(size + 1); + + if (!ptr) + return NULL; + + dprintf(stderr, "%s, %s calling __bound_new_region(%p, %x)\n", + __FILE__, __FUNCTION__, ptr, (unsigned)size); + + __bound_new_region(ptr, size); + return ptr; +} + +void *__bound_memalign(size_t size, size_t align, const void *caller) +{ + void *ptr; + + restore_malloc_hooks(); + +#ifndef HAVE_MEMALIGN + if (align > 4) { + /* XXX: handle it ? */ + ptr = NULL; + } else { + /* we suppose that malloc aligns to at least four bytes */ + ptr = malloc(size + 1); + } +#else + /* we allocate one more byte to ensure the regions will be + separated by at least one byte. With the glibc malloc, it may + be in fact not necessary */ + ptr = memalign(size + 1, align); +#endif + + install_malloc_hooks(); + + if (!ptr) + return NULL; + + dprintf(stderr, "%s, %s calling __bound_new_region(%p, %x)\n", + __FILE__, __FUNCTION__, ptr, (unsigned)size); + + __bound_new_region(ptr, size); + return ptr; +} + +void __bound_free(void *ptr, const void *caller) +{ + if (ptr == NULL) + return; + if (__bound_delete_region(ptr) != 0) + bound_error("freeing invalid region"); + + libc_free(ptr); +} + +void *__bound_realloc(void *ptr, size_t size, const void *caller) +{ + void *ptr1; + size_t old_size; + + if (size == 0) { + __bound_free(ptr, caller); + return NULL; + } else { + ptr1 = __bound_malloc(size, caller); + if (ptr == NULL || ptr1 == NULL) + return ptr1; + old_size = get_region_size(ptr); + if (old_size == EMPTY_SIZE) + bound_error("realloc'ing invalid pointer"); + memcpy(ptr1, ptr, old_size); + __bound_free(ptr, caller); + return ptr1; + } +} + +#ifndef CONFIG_TCC_MALLOC_HOOKS +void *__bound_calloc(size_t nmemb, size_t size) +{ + void *ptr; + size = size * nmemb; + ptr = __bound_malloc(size, NULL); + if (!ptr) + return NULL; + memset(ptr, 0, size); + return ptr; +} +#endif + +#if 0 +static void bound_dump(void) +{ + BoundEntry *page, *e; + size_t i, j; + + fprintf(stderr, "region dump:\n"); + for(i=0;i<BOUND_T1_SIZE;i++) { + page = __bound_t1[i]; + for(j=0;j<BOUND_T2_SIZE;j++) { + e = page + j; + /* do not print invalid or empty entries */ + if (e->size != EMPTY_SIZE && e->start != 0) { + fprintf(stderr, "%08x:", + (i << (BOUND_T2_BITS + BOUND_T3_BITS)) + + (j << BOUND_T3_BITS)); + do { + fprintf(stderr, " %08lx:%08lx", e->start, e->start + e->size); + e = e->next; + } while (e != NULL); + fprintf(stderr, "\n"); + } + } + } +} +#endif + +/* some useful checked functions */ + +/* check that (p ... p + size - 1) lies inside 'p' region, if any */ +static void __bound_check(const void *p, size_t size) +{ + if (size == 0) + return; + p = __bound_ptr_add((void *)p, size - 1); + if (p == INVALID_POINTER) + bound_error("invalid pointer"); +} + +void *__bound_memcpy(void *dst, const void *src, size_t size) +{ + void* p; + + dprintf(stderr, "%s %s: start, dst=%p src=%p size=%x\n", + __FILE__, __FUNCTION__, dst, src, (unsigned)size); + + __bound_check(dst, size); + __bound_check(src, size); + /* check also region overlap */ + if (src >= dst && src < dst + size) + bound_error("overlapping regions in memcpy()"); + + p = memcpy(dst, src, size); + + dprintf(stderr, "%s %s: end, p=%p\n", __FILE__, __FUNCTION__, p); + return p; +} + +void *__bound_memmove(void *dst, const void *src, size_t size) +{ + __bound_check(dst, size); + __bound_check(src, size); + return memmove(dst, src, size); +} + +void *__bound_memset(void *dst, int c, size_t size) +{ + __bound_check(dst, size); + return memset(dst, c, size); +} + +/* XXX: could be optimized */ +int __bound_strlen(const char *s) +{ + const char *p; + size_t len; + + len = 0; + for(;;) { + p = __bound_ptr_indir1((char *)s, len); + if (p == INVALID_POINTER) + bound_error("bad pointer in strlen()"); + if (*p == '\0') + break; + len++; + } + return len; +} + +char *__bound_strcpy(char *dst, const char *src) +{ + size_t len; + void *p; + + dprintf(stderr, "%s %s: strcpy start, dst=%p src=%p\n", + __FILE__, __FUNCTION__, dst, src); + len = __bound_strlen(src); + p = __bound_memcpy(dst, src, len + 1); + dprintf(stderr, "%s %s: strcpy end, p = %p\n", + __FILE__, __FUNCTION__, p); + return p; +} |