libdislocator, optional huge pages support.

This commit is contained in:
David Carlier 2019-11-06 22:27:04 +00:00
parent db7c990346
commit cc301c18d5

View File

@ -26,6 +26,10 @@
#include <errno.h>
#include <sys/mman.h>
#ifdef __APPLE__
#include <mach/vm_statistics.h>
#endif
#include "config.h"
#include "types.h"
@ -37,6 +41,8 @@
#define MAP_ANONYMOUS MAP_ANON
#endif /* !MAP_ANONYMOUS */
#define SUPER_PAGE_SIZE 1<<21
/* Error / message handling: */
#define DEBUGF(_x...) \
@ -105,6 +111,7 @@ static __thread u32 call_depth; /* To avoid recursion via fprintf() */
static void* __dislocator_alloc(size_t len) {
void* ret;
int flags, fd, sp;
if (total_mem + len > max_mem || total_mem + len < total_mem) {
@ -116,11 +123,27 @@ static void* __dislocator_alloc(size_t len) {
}
flags = MAP_PRIVATE | MAP_ANONYMOUS;
fd = -1;
#if defined(USEHUGEPAGE)
sp = (len >= SUPER_PAGE_SIZE && !(len % SUPER_PAGE_SIZE));
#if defined(__APPLE__)
if (sp) fd = VM_FLAGS_SUPERPAGE_SIZE_2MB;
#elif defined(__linux__)
if (sp) flags |= MAP_HUGETLB;
#elif defined(__FreeBSD__)
if (sp) flags |= MAP_ALIGNED_SUPER;
#endif
#else
(void)sp;
#endif
/* We will also store buffer length and a canary below the actual buffer, so
let's add 8 bytes for that. */
ret = mmap(NULL, (1 + PG_COUNT(len + 8)) * PAGE_SIZE, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
flags, fd, 0);
if (ret == MAP_FAILED) {
@ -315,11 +338,11 @@ void *aligned_alloc(size_t align, size_t len) {
__attribute__((constructor)) void __dislocator_init(void) {
u8* tmp = getenv("AFL_LD_LIMIT_MB");
u8* tmp = (u8 *)getenv("AFL_LD_LIMIT_MB");
if (tmp) {
max_mem = atoi(tmp) * 1024 * 1024;
max_mem = atoi((char *)tmp) * 1024 * 1024;
if (!max_mem) FATAL("Bad value for AFL_LD_LIMIT_MB");
}