linux version magic

version magic '6.1.24+ SMP mod_unload riscv' should be '6.1.24-gf4f652de5a3f

SYSCALL_DEFINE3(init_module, void __user *, umod,
		unsigned long, len, const char __user *, uargs)
{
	int err;
	struct load_info info = { };

	err = may_init_module();
	if (err)
		return err;

	pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
	       umod, len, uargs);

	err = copy_module_from_user(umod, len, &info);
	if (err)
		return err;

	return load_module(&info, uargs, 0);
}

SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
{
	struct load_info info = { };
	void *buf = NULL;
	int len;
	int err;

	err = may_init_module();
	if (err)
		return err;

	pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);

	if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
		      |MODULE_INIT_IGNORE_VERMAGIC
		      |MODULE_INIT_COMPRESSED_FILE))
		return -EINVAL;

	len = kernel_read_file_from_fd(fd, 0, &buf, INT_MAX, NULL,
				       READING_MODULE);
	if (len < 0)
		return len;

	if (flags & MODULE_INIT_COMPRESSED_FILE) {
		err = module_decompress(&info, buf, len);
		vfree(buf); /* compressed data is no longer needed */
		if (err)
			return err;
	} else {
		info.hdr = buf;
		info.len = len;
	}

	return load_module(&info, uargs, flags);
}

finit_module flags会带IGNORE

busybox 1.36仍然没有支持 IGNORE只能关闭

# CONFIG_LOCALVERSION_AUTO is not set

static int load_module(const char *fname, const char *options)
{
#if 1
	int r;
	size_t len = MAXINT(ssize_t);
	char *module_image;

	if (!options)
		options = "";

	dbg1_error_msg("load_module('%s','%s')", fname, options);

	/*
	 * First we try finit_module if available.  Some kernels are configured
	 * to only allow loading of modules off of secure storage (like a read-
	 * only rootfs) which needs the finit_module call.  If it fails, we fall
	 * back to normal module loading to support compressed modules.
	 */
	r = 1;
# ifdef __NR_finit_module
	{
		int fd = open(fname, O_RDONLY | O_CLOEXEC);
		if (fd >= 0) {
			r = finit_module(fd, options, 0) != 0;
			close(fd);
		}
	}
# endif