Move comment about adding 8 bytes to buffer length to the line where we

  actually add 8 bytes
Remove defunct TODO for posix_memalign as the function now exists
Add wrapper for malloc_usable_size

1 files changed, 9 insertions, 8 deletions

diff --git a/libdislocator/libdislocator.so.c b/libdislocator/libdislocator.so.c
index 1fbfe9d6..72d280e6 100644
--- a/libdislocator/libdislocator.so.c
+++ b/libdislocator/libdislocator.so.c
@@ -183,6 +183,9 @@ static void *__dislocator_alloc(size_t len) {
   else
     rlen = len;
 
+  /* We will also store buffer length and a canary below the actual buffer, so
+     let's add 8 bytes for that. */
+
   tlen = (1 + PG_COUNT(rlen + 8)) * PAGE_SIZE;
   flags = MAP_PRIVATE | MAP_ANONYMOUS;
   fd = -1;
@@ -200,9 +203,6 @@ static void *__dislocator_alloc(size_t len) {
   (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 = (u8 *)mmap(NULL, tlen, PROT_READ | PROT_WRITE, flags, fd, 0);
 #if defined(USEHUGEPAGE)
   /* We try one more time with regular call */
@@ -296,10 +296,6 @@ void *calloc(size_t elem_len, size_t elem_cnt) {
 
 }
 
-/* TODO: add a wrapper for posix_memalign, otherwise apps who use it,
-   will fail when freeing the memory.
-*/
-
 /* The wrapper for malloc(). Roughly the same, also clobbers the returned
    memory (unlike calloc(), malloc() is not guaranteed to return zeroed
    memory). */
@@ -468,6 +464,12 @@ void *reallocarray(void *ptr, size_t elem_len, size_t elem_cnt) {
 
 }
 
+size_t malloc_usable_size(void *ptr) {
+
+   return PTR_L(ptr);
+
+}
+
 __attribute__((constructor)) void __dislocator_init(void) {
 
   u8 *tmp = (u8 *)getenv("AFL_LD_LIMIT_MB");
@@ -492,4 +494,3 @@ __attribute__((constructor)) void __dislocator_init(void) {
   align_allocations = !!getenv("AFL_ALIGNED_ALLOC");
 
 }
-