a bounds checking code for the ARCH=x86_64

3 files changed, 119 insertions, 54 deletions

diff --git a/lib/Makefile b/lib/Makefile
index aa3984b..348cb72 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -44,7 +44,7 @@ native : TCC = $(TOP)/tcc$(EXESUF)
 cross : TCC = $(TOP)/$(TARGET)-tcc$(EXESUF)
 
 I386_O = libtcc1.o alloca86.o alloca86-bt.o $(BCHECK_O)
-X86_64_O = libtcc1.o alloca86_64.o
+X86_64_O = libtcc1.o alloca86_64.o alloca86_64-bt.o $(BCHECK_O)
 ARM_O = libtcc1.o armeabi.o alloca-arm.o
 WIN32_O = $(I386_O) crt1.o wincrt1.o dllcrt1.o dllmain.o chkstk.o
 WIN64_O = $(X86_64_O) crt1.o wincrt1.o dllcrt1.o dllmain.o chkstk.o
diff --git a/lib/alloca86_64-bt.S b/lib/alloca86_64-bt.S
new file mode 100644
index 0000000..ab8629d
--- /dev/null
+++ b/lib/alloca86_64-bt.S
@@ -0,0 +1,60 @@
+/* ---------------------------------------------- */
+/* alloca86_64.S */
+
+.globl __bound_alloca
+__bound_alloca:
+
+#ifdef TCC_TARGET_PE
+    # bound checking is not implemented
+    pop     %rdx
+    mov     %rcx,%rax
+    add     $15,%rax
+    and     $-16,%rax
+    jz      p3
+
+p1:
+    cmp     $4096,%rax
+    jbe     p2
+    test    %rax,-4096(%rsp)
+    sub     $4096,%rsp
+    sub     $4096,%rax
+    jmp p1
+p2:
+
+    sub     %rax,%rsp
+    mov     %rsp,%rax
+    add     $32,%rax
+
+p3:
+    push    %rdx
+    ret
+#else
+    pop     %rdx
+    mov     %rdi,%rax
+    movl    %rax,%rsi	# size, a second parm to the __bound_new_region
+
+    add     $15,%rax
+    and     $-16,%rax
+    jz      p3
+
+
+    sub     %rax,%rsp
+    mov     %rsp,%rdi	# pointer, a first parm to the __bound_new_region
+    mov     %rsp,%rax
+
+    push    %rdx
+    push    %rax
+    call   __bound_new_region
+    pop     %rax
+    pop     %rdx
+
+p3:
+    push    %rdx
+    ret
+#endif
+
+/* mark stack as nonexecutable */
+#if defined __ELF__ && defined __linux__
+    .section    .note.GNU-stack,"",@progbits
+#endif
+/* ---------------------------------------------- */
diff --git a/lib/bcheck.c b/lib/bcheck.c
index 7dcb36e..829e33d 100644
--- a/lib/bcheck.c
+++ b/lib/bcheck.c
@@ -31,6 +31,12 @@
 
 /* #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 */
@@ -50,12 +56,12 @@
 
 #define BOUND_T1_BITS 13
 #define BOUND_T2_BITS 11
-#define BOUND_T3_BITS (32 - BOUND_T1_BITS - BOUND_T2_BITS)
+#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 (1 << BOUND_T1_BITS)
 #define BOUND_T2_SIZE (1 << BOUND_T2_BITS)
 #define BOUND_T3_SIZE (1 << BOUND_T3_BITS)
-#define BOUND_E_BITS  4
 
 #define BOUND_T23_BITS (BOUND_T2_BITS + BOUND_T3_BITS)
 #define BOUND_T23_SIZE (1 << BOUND_T23_BITS)
@@ -64,7 +70,7 @@
 /* this pointer is generated when bound check is incorrect */
 #define INVALID_POINTER ((void *)(-2))
 /* size of an empty region */
-#define EMPTY_SIZE        0xffffffff
+#define EMPTY_SIZE  ((size_t)(-1))
 /* size of an invalid region */
 #define INVALID_SIZE      0
 
@@ -168,9 +174,7 @@ void * FASTCALL __bound_ptr_add(void *p, size_t offset)
 
     __bound_init();
 
-#if defined(BOUND_DEBUG)
-    printf("%s %s: 0x%x %d\n", __FILE__, __FUNCTION__, (int)p, offset);
-#endif
+    dprintf(stderr, "%s %s: %p %p\n", __FILE__, __FUNCTION__, p, offset);
 
     e = __bound_t1[addr >> (BOUND_T2_BITS + BOUND_T3_BITS)];
     e = (BoundEntry *)((char *)e + 
@@ -197,6 +201,8 @@ void * FASTCALL __bound_ptr_indir ## dsize (void *p, size_t offset)     \
     size_t addr = (size_t)p;                                            \
     BoundEntry *e;                                                      \
                                                                         \
+    dprintf(stderr, "%s %s: %p %p start\n", __FILE__, __FUNCTION__, p, offset);	\
+									\
     __bound_init();							\
     e = __bound_t1[addr >> (BOUND_T2_BITS + BOUND_T3_BITS)];            \
     e = (BoundEntry *)((char *)e +                                      \
@@ -212,6 +218,7 @@ void * FASTCALL __bound_ptr_indir ## dsize (void *p, size_t offset)     \
 	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;                                                  \
 }
 
@@ -232,9 +239,8 @@ BOUND_PTR_INDIR(16)
 void FASTCALL __bound_local_new(void *p1) 
 {
     size_t addr, size, fp, *p = p1;
-#ifdef BOUND_DEBUG
-    fprintf(stderr, "%s, %s start p1=%p *p1=%p\n", __FILE__, __FUNCTION__, p, *p);
-#endif
+
+    dprintf(stderr, "%s, %s start p1=%p\n", __FILE__, __FUNCTION__, p);
     GET_CALLER_FP(fp);
     for(;;) {
         addr = p[0];
@@ -245,9 +251,7 @@ void FASTCALL __bound_local_new(void *p1)
         p += 2;
         __bound_new_region((void *)addr, size);
     }
-#ifdef BOUND_DEBUG
-    fprintf(stderr, "%s, %s end\n", __FILE__, __FUNCTION__);
-#endif
+    dprintf(stderr, "%s, %s end\n", __FILE__, __FUNCTION__);
 }
 
 /* called when leaving a function to delete all the local regions */
@@ -268,7 +272,7 @@ void FASTCALL __bound_local_delete(void *p1)
 static BoundEntry *__bound_new_page(void)
 {
     BoundEntry *page;
-    int i;
+    size_t i;
 
     page = libc_malloc(sizeof(BoundEntry) * BOUND_T2_SIZE);
     if (!page)
@@ -296,11 +300,11 @@ static void bound_free_entry(BoundEntry *e)
     libc_free(e);
 }
 
-static inline BoundEntry *get_page(int index)
+static BoundEntry *get_page(size_t index)
 {
     BoundEntry *page;
     page = __bound_t1[index];
-    if (page == __bound_empty_t2 || page == __bound_invalid_t2) {
+    if (!page || page == __bound_empty_t2 || page == __bound_invalid_t2) {
         /* create a new page if necessary */
         page = __bound_new_page();
         __bound_t1[index] = page;
@@ -325,7 +329,7 @@ static void mark_invalid(size_t addr, size_t size)
         t2_end = 1 << (BOUND_T1_BITS + BOUND_T2_BITS);
 
 #if 0
-    printf("mark_invalid: start = %x %x\n", t2_start, t2_end);
+    dprintf(stderr, "mark_invalid: start = %x %x\n", t2_start, t2_end);
 #endif
     
     /* first we handle full pages */
@@ -364,7 +368,7 @@ static void mark_invalid(size_t addr, size_t size)
 
 void __bound_init(void)
 {
-    int i;
+    size_t i;
     BoundEntry *page;
     size_t start, size;
     size_t *p;
@@ -375,9 +379,7 @@ void __bound_init(void)
 
     inited = 1;
 
-#ifdef BOUND_DEBUG
-    fprintf(stderr, "%s, %s() start\n", __FILE__, __FUNCTION__);
-#endif
+    dprintf(stderr, "%s, %s() start\n", __FILE__, __FUNCTION__);
 
     /* save malloc hooks and install bound check hooks */
     install_malloc_hooks();
@@ -445,19 +447,18 @@ void __bound_init(void)
         __bound_new_region((void *)p[0], p[1]);
         p += 2;
     }
-#ifdef BOUND_DEBUG
-    fprintf(stderr, "%s, %s() end\n\n", __FILE__, __FUNCTION__);
-#endif
+
+    dprintf(stderr, "%s, %s() end\n\n", __FILE__, __FUNCTION__);
 }
 
 void __bound_main_arg(void **p)
 {
     void *start = p;
     while (*p++);
-#ifdef BOUND_DEBUG
-	fprintf(stderr, "%s, %s calling __bound_new_region(%p, %p)\n", 
+
+    dprintf(stderr, "%s, %s calling __bound_new_region(%p, %p)\n", 
            __FILE__, __FUNCTION__, (void *) p - start);
-#endif
+
     __bound_new_region(start, (void *) p - start);
 }
 
@@ -495,10 +496,8 @@ void __bound_new_region(void *p, size_t size)
 
     __bound_init();
 
-#ifdef BOUND_DEBUG
-    fprintf(stderr, "%s, %s(%p, %p) start\n", 
+    dprintf(stderr, "%s, %s(%p, %p) start\n", 
            __FILE__, __FUNCTION__, p, size);
-#endif
 
     start = (size_t)p;
     end = start + size;
@@ -553,9 +552,8 @@ void __bound_new_region(void *p, size_t size)
         }
         add_region(e, start, size);
     }
-#ifdef BOUND_DEBUG
-    fprintf(stderr, "%s, %s end\n", __FILE__, __FUNCTION__);
-#endif
+
+    dprintf(stderr, "%s, %s end\n", __FILE__, __FUNCTION__);
 }
 
 /* delete a region */
@@ -610,9 +608,7 @@ int __bound_delete_region(void *p)
 
     __bound_init();
 
-#ifdef BOUND_DEBUG
-    fprintf(stderr, "%s %s() start\n", __FILE__, __FUNCTION__);
-#endif
+    dprintf(stderr, "%s %s() start\n", __FILE__, __FUNCTION__);
 
     start = (size_t)p;
     t1_start = start >> (BOUND_T2_BITS + BOUND_T3_BITS);
@@ -681,9 +677,7 @@ int __bound_delete_region(void *p)
         delete_region(e, p, empty_size);
     }
 
-#ifdef BOUND_DEBUG
-    fprintf(stderr, "%s %s() end\n", __FILE__, __FUNCTION__);
-#endif
+    dprintf(stderr, "%s %s() end\n", __FILE__, __FUNCTION__);
 
     return 0;
 }
@@ -771,10 +765,9 @@ void *__bound_malloc(size_t size, const void *caller)
     if (!ptr)
         return NULL;
 
-#ifdef BOUND_DEBUG
-    fprintf(stderr, "%s, %s calling __bound_new_region(%p, %p)\n", 
+    dprintf(stderr, "%s, %s calling __bound_new_region(%p, %p)\n", 
            __FILE__, __FUNCTION__, ptr, size);
-#endif
+
     __bound_new_region(ptr, size);
     return ptr;
 }
@@ -805,10 +798,9 @@ void *__bound_memalign(size_t size, size_t align, const void *caller)
     if (!ptr)
         return NULL;
 
-#ifdef BOUND_DEBUG
-    fprintf(stderr, "%s, %s calling __bound_new_region(%p, %p)\n", 
+    dprintf(stderr, "%s, %s calling __bound_new_region(%p, %p)\n", 
            __FILE__, __FUNCTION__, ptr, size);
-#endif
+
     __bound_new_region(ptr, size);
     return ptr;
 }
@@ -861,23 +853,23 @@ void *__bound_calloc(size_t nmemb, size_t size)
 static void bound_dump(void)
 {
     BoundEntry *page, *e;
-    int i, j;
+    size_t i, j;
 
-    printf("region dump:\n");
+    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) {
-                printf("%08x:", 
+                fprintf(stderr, "%08x:", 
                        (i << (BOUND_T2_BITS + BOUND_T3_BITS)) + 
                        (j << BOUND_T3_BITS));
                 do {
-                    printf(" %08lx:%08lx", e->start, e->start + e->size);
+                    fprintf(stderr, " %08lx:%08lx", e->start, e->start + e->size);
                     e = e->next;
                 } while (e != NULL);
-                printf("\n");
+                fprintf(stderr, "\n");
             }
         }
     }
@@ -891,19 +883,27 @@ static void __bound_check(const void *p, size_t size)
 {
     if (size == 0)
         return;
-    p = __bound_ptr_add((void *)p, size);
+    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=%p\n", __FILE__, __FUNCTION__, dst, src, 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()");
-    return memcpy(dst, src, size);
+
+    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)
@@ -939,7 +939,12 @@ int __bound_strlen(const char *s)
 
 char *__bound_strcpy(char *dst, const char *src)
 {
-    int len;
+    size_t len;
+    void *p;
+
+    dprintf(stderr, "%s %s: strcpy start, dst=%p src=%p\n", __FILE__, __FUNCTION__, dst, src);
     len = __bound_strlen(src);
-    return __bound_memcpy(dst, src, len + 1);
+    p = __bound_memcpy(dst, src, len + 1);
+    dprintf(stderr, "%s %s: strcpy end, p=%p\n", __FILE__, __FUNCTION__, dst, src, p);
+    return p;
 }