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// Simplified version of mempool.c, that is more oriented towards
// checking that the description of invalid addresses is correct.
#include <stdio.h>
#include <unistd.h>
#include "tests/sys_mman.h"
#include <assert.h>
#include <stdlib.h>
#include "../memcheck.h"
#define SUPERBLOCK_SIZE 100000
#define REDZONE_SIZE 8
typedef struct _level_list
{
struct _level_list *next;
char *where;
// Padding ensures the struct is the same size on 32-bit and 64-bit
// machines.
char padding[16 - 2*sizeof(char*)];
} level_list;
typedef struct _pool {
char *mem;
char *where;
level_list *levels;
int size, left;
// Padding ensures the struct is the same size on 32-bit and 64-bit
// machines.
char padding[24 - 3*sizeof(char*)];
} pool;
pool *make_pool( int use_mmap )
{
pool *p;
if (use_mmap) {
p = (pool *)mmap(0, sizeof(pool), PROT_READ|PROT_WRITE|PROT_EXEC,
MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
p->where = p->mem = (char *)mmap(NULL, SUPERBLOCK_SIZE,
PROT_READ|PROT_WRITE|PROT_EXEC,
MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
} else {
p = (pool *)malloc(sizeof(pool));
p->where = p->mem = (char *)malloc(SUPERBLOCK_SIZE);
}
p->size = p->left = SUPERBLOCK_SIZE;
p->levels = NULL;
(void) VALGRIND_MAKE_MEM_NOACCESS(p->where, SUPERBLOCK_SIZE);
return p;
}
void push(pool *p, int use_mmap )
{
level_list *l;
if (use_mmap)
l = (level_list *)mmap(0, sizeof(level_list),
PROT_READ|PROT_WRITE|PROT_EXEC,
MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
else
l = (level_list *)malloc(sizeof(level_list));
l->next = p->levels;
l->where = p->where;
VALGRIND_CREATE_MEMPOOL(l->where, REDZONE_SIZE, 0);
p->levels = l;
}
void pop(pool *p, int use_mmap)
{
level_list *l = p->levels;
p->levels = l->next;
VALGRIND_DESTROY_MEMPOOL(l->where);
(void) VALGRIND_MAKE_MEM_NOACCESS(l->where, p->where-l->where);
p->where = l->where;
if (use_mmap)
munmap(l, sizeof(level_list));
else
free(l);
}
void destroy_pool(pool *p, int use_mmap)
{
level_list *l = p->levels;
while(l) {
pop(p, use_mmap);
}
if (use_mmap) {
munmap(p->mem, SUPERBLOCK_SIZE);
munmap(p, sizeof(pool));
} else {
free(p->mem);
free(p);
}
}
char *allocate(pool *p, int size)
{
char *where;
p->left -= size + (REDZONE_SIZE*2);
where = p->where + REDZONE_SIZE;
p->where += size + (REDZONE_SIZE*2);
VALGRIND_MEMPOOL_ALLOC(p->levels->where, where, size);
return where;
}
//-------------------------------------------------------------------------
// Rest
//-------------------------------------------------------------------------
void test(void)
{
char *x1, *x2;
char res = 0;
// p1 is a malloc-backed pool
pool *p1 = make_pool(0);
// p2 is a mmap-backed pool
pool *p2 = make_pool(1);
push(p1, 0);
push(p2, 1);
x1 = allocate(p1, 10);
x2 = allocate(p2, 20);
fprintf(stderr,
"\n------ out of range reads in malloc-backed pool ------\n\n");
res += x1[-1];
res += x1[10];
fprintf(stderr,
"\n------ out of range reads in mmap-backed pool ------\n\n");
res += x2[-1]; // invalid
res += x2[20]; // invalid
fprintf(stderr,
"\n------ read free in malloc-backed pool ------\n\n");
VALGRIND_MEMPOOL_FREE(p1, x1);
res += x1[5];
fprintf(stderr,
"\n------ read free in mmap-backed pool ------\n\n");
VALGRIND_MEMPOOL_FREE(p2, x2);
res += x2[11];
fprintf(stderr,
"\n------ double free in malloc-backed pool ------\n\n");
VALGRIND_MEMPOOL_FREE(p1, x1);
fprintf(stderr,
"\n------ double free in mmap-backed pool ------\n\n");
VALGRIND_MEMPOOL_FREE(p2, x2);
{
// test that redzone are still protected even if the user forgets
// to mark the superblock noaccess.
char superblock[100];
VALGRIND_CREATE_MEMPOOL(superblock, REDZONE_SIZE, 0);
// User should mark the superblock no access to benefit
// from full Valgrind memcheck protection.
// VALGRIND_MEMPOOL_ALLOC will however still ensure the
// redzones are protected.
VALGRIND_MEMPOOL_ALLOC(superblock, superblock+30, 10);
res += superblock[30]; // valid
res += superblock[39]; // valid
fprintf(stderr,
"\n------ 2 invalid access in 'no no-access superblock' ---\n\n");
res += superblock[29]; // invalid
res += superblock[40]; // invalid
VALGRIND_DESTROY_MEMPOOL(superblock);
}
// claim res is used, so gcc can't nuke this all
__asm__ __volatile__("" : : "r"(res));
fprintf(stderr,
"\n------ done ------\n\n");
pop(p1, 0);
pop(p2, 1);
destroy_pool(p1, 0);
destroy_pool(p2, 1);
}
int main(void)
{
test();
return 0;
}
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