Can't find my segmentation fault in my malloc shared library

Question

I recoded malloc free and realloc in c using mmap and munmap. I compiled them as a shared library .so file.

Here is a simple test:

#include <stdlib.h>

int main() {
    int i;
    char *addr;
    i = 0;
    while (i < 1024)
    {
        addr = (char*)malloc(1024);
        addr[0] = 42;
        i++;
    }
    return (0);
}

Here is a run.sh that must replace the stdlib by my shared library:

#/bin/sh
export DYLD_LIBRARY_PATH=.
export DYLD_INSERT_LIBRARIES="libft_malloc.so"
export DYLD_FORCE_FLAT_NAMESPACE=1
$@

The problem is that when i am compiling directly the test file with my shared library and replacing the header in it, it is working well:

-> gcc test1.c libft_malloc.so
-> ./a.out
-> no error

But when i am running it with the run.sh that should just replace the official malloc library by my libft_malloc.so file, i am getting a segfault:

-> gcc test1.c
-> ./run.sh ./a.out
-> ./run.sh: line 5: 73502 Segmentation fault: 11  $@

I know the error is in my code and not in the run.sh or in the test.c because they are the officials files i must use to test my library in my school and those files are working well on other malloc repositories, but i can't find what can be the problem.

Here is my repository: https://github.com/Shirakawa42/malloc.git

I tried debugged by placing write() everywhere but the segfault don't seems to be in the malloc, so i'm lost.

edit: It also segfault if we run a test without any malloc, but just by loading my library:

#include <stdlib.h>

int main() {
    int i;
    i = 0;
    while (i < 1024)
    {
        i++;
    }
    return (0);
}

-> gcc test1.c
-> ./run.sh ./a.out
-> ./run.sh: line 5: 74764 Segmentation fault: 11  $@

edit 2: Compiling with flag fsanitize=address repair the segfault, but it's absolutely not optimal

edit 3: Setting the 2 first export manually in shell tell me:

dyld: warning: could not load inserted library 'libft_malloc.so' into library validated process because no suitable image found.  Did find:
    libft_malloc.so: code signing blocked mmap() of 'libft_malloc.so'

and after setting the third export all my actions make me segfault, like ls and vim, cd made me abort

Answer 1

dyld: warning: could not load inserted library 'libft_malloc.so' into library validated process because no suitable image found.  Did find:
    libft_malloc.so: code signing blocked mmap() of 'libft_malloc.so'

This error append when there are a segfault in your malloc or free, repairing free made it work.