Get absolute executable process path in Linux kernel

exe_from_mm

#include <linux/err.h>

char *exe_from_mm(const struct mm_struct *mm, char *buffer, int length)
{
	char *p = NULL;
	struct vm_area_struct *vma;

	if(mm == NULL)
	{
		return NULL;
	}

	down_read(&mm->mmap_sem);

	vma = mm->mmap;

	while(vma)
	{
		if((vma->vm_flags & VM_EXECUTABLE) && vma->vm_file)
		{
			break;
		}
			
		vma = vma->vm_next;
	}

	if (vma && vma->vm_file)
	{
		p = call_d_path(vma->vm_file, buffer, length);
		
		if(IS_ERR(p))
		{
                	up_read(&mm->mmap_sem);
			return NULL;
		}
	}

	up_read(&mm->mmap_sem);
	return p;
}