ld-preload

I have static linked binary (ELF file) it doesn't have dynamic segment, .dymsym sections and it doesn't perform LD_PRELOAD command and etc. How could i create fake dummy dynamic segment to activate dynamic loader and perform LD_PRELOAD command? How could i create fake dummy dynamic segment to activate dynamic loader and perform LD_PRELOAD command? You can't. Even if you could, getting LD_PRELOAD to preload something would still be useless: usually you want to interpose some symbols in your LD_PRELOAD ed library, but that requires these symbols to be unresolved in the main binary, or at least

I am using LD_PRELOAD to hook a library function, and in Linux it works perfectly. But I cannot figure out how to do the equivalent in OSX. The setup I have on Linux is as follows: The code is: #include <stdio.h> #include <dlfcn.h> #include <stdlib.h> #include <unistd.h> #include <ruby.h> void rb_raise(unsigned long exc, const char *fmt, ...) { static void (*libruby_rb_raise) (unsigned long exc, const char *fmt, ...) = NULL; void * handle; char * error; if (!libruby_rb_raise) { handle = dlopen("/path/to/libruby.so", RTLD_LAZY); if (!handle) { fputs(dlerror(), stderr); exit(1); } libruby_rb

I am trying to use LD_PRELOAD to preload a library with an application that has setuid permissions. Tried LD_PRELOAD at first, and it seemed like it was being ignored with the setuid binary, though it was working when I tried it with others like ls , dir etc. From the documentation of LD_PRELOAD: LD_PRELOAD A whitespace-separated list of additional, user-specified, ELF shared libraries to be loaded before all others. This can be used to selectively override functions in other shared libraries. For set- user-ID/set-group-ID ELF binaries, only libraries in the standard search directories that

I'm trying to interpose malloc/free/calloc/realloc etc with some interposers via LD_PRELOAD. In my small test, only malloc seems to be interposed, even though free is detected (see output). I'd expect the output to contain a line "NANO: free(x)" - but this line is missing. Given // compile with: gcc test.cc #include <stdio.h> #include <stdlib.h> int main(int argc, char* argv[]) { void* p = malloc(123); printf("HOST p=%p\n", p); free(p); } And // compile with: g++ -O2 -Wall -fPIC -ldl -o libnano.so -shared main.cc #include <stdio.h> #include <dlfcn.h> typedef void *(*MallocFunc)(size_t size);