hook malloc_zone_malloc EXC_BAD_ACCESS (code=2, address=0x10ecb50cd)

[wMellon]

I try to hook malloc_zone_malloc, but I get crash.Why?

void *my_malloc_zone_malloc(malloc_zone_t *zone, size_t size){
printf("Calling real malloc( %zu)\n", size);
return malloc_zone_malloc(zone, size);
}

void my_malloc_zone_free(malloc_zone_t *zone, void *ptr){
printf("Calling real free( %zu)\n",malloc_size(ptr));

return malloc_zone_free(zone, ptr);

}

rebind_symbols((struct rebinding[2]){{"malloc_zone_malloc", my_malloc_zone_malloc,(void*)&malloc_zone_malloc}, {"malloc_zone_free", my_malloc_zone_free,(void*)&malloc_zone_free}}, 2);

[PotatoMapper]

I try to avoid contributing responses to poorly defined or not an issue with the project itself.

But it does not appear you ever declared a "Holder" pointer function where the original implementation of malloc_zone_malloc OR malloc_zone_free could be invoked from.

If you reference the homepage of the repo it clearly outlines a very simple and clear example of the proper way to swap the implementations.

I very quickly typed up what a single hook for malloc_zone_malloc should look like. Beware copy and pasting this as I typed it up on the fly and am EXTREMELY prone to overlooking typos.

#import "fishhook.h"
#import <Wherever_Malloc_structs_are_defined>

static void * (*orig_malloc_zone_malloc)(malloc_zone_t, size_t);

void * my_malloc_zone_malloc(malloc_zone_t *zone, size_t size) {
	// Do Stuff here
	// Log whatever you wanna play with or what have you
	orig_malloc_zone_malloc(zone,size);
}

rebind_symbols((struct rebinding[1])
	{{"malloc_zone_malloc", my_malloc_zone_malloc, (void *)&orig_malloc_zone_malloc}},1);

Note the static definition of the ptr func for the original implementation you do not have.

Try this and see if you still run into issues. Either way this is not an issue with fishhook itself at first glance, and should really be closed until you get to an error that is indicative of a failure on the project itself.