1 files changed, 124 insertions, 0 deletions
diff --git a/src/shared/module-util.c b/src/shared/module-util.c
new file mode 100644
index 0000000..951701d
--- /dev/null
+++ b/src/shared/module-util.c
@@ -0,0 +1,124 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <errno.h>
+
+#include "module-util.h"
+#include "proc-cmdline.h"
+#include "strv.h"
+
+static int denylist_modules(const char *p, char ***denylist) {
+        _cleanup_strv_free_ char **k = NULL;
+
+        assert(p);
+        assert(denylist);
+
+        k = strv_split(p, ",");
+        if (!k)
+                return -ENOMEM;
+
+        if (strv_extend_strv(denylist, k, true) < 0)
+                return -ENOMEM;
+
+        return 0;
+}
+
+static int parse_proc_cmdline_item(const char *key, const char *value, void *data) {
+        int r;
+
+        if (proc_cmdline_key_streq(key, "module_blacklist")) {
+
+                if (proc_cmdline_value_missing(key, value))
+                        return 0;
+
+                r = denylist_modules(value, data);
+                if (r < 0)
+                        return r;
+        }
+
+        return 0;
+}
+
+int module_load_and_warn(struct kmod_ctx *ctx, const char *module, bool verbose) {
+        const int probe_flags = KMOD_PROBE_APPLY_BLACKLIST;
+        struct kmod_list *itr;
+        _cleanup_(kmod_module_unref_listp) struct kmod_list *modlist = NULL;
+        _cleanup_strv_free_ char **denylist = NULL;
+        bool denylist_parsed = false;
+        int r;
+
+        /* verbose==true means we should log at non-debug level if we
+         * fail to find or load the module. */
+
+        log_debug("Loading module: %s", module);
+
+        r = kmod_module_new_from_lookup(ctx, module, &modlist);
+        if (r < 0)
+                return log_full_errno(verbose ? LOG_ERR : LOG_DEBUG, r,
+                                      "Failed to look up module alias '%s': %m", module);
+
+        if (!modlist)
+                return log_full_errno(verbose ? LOG_ERR : LOG_DEBUG,
+                                      SYNTHETIC_ERRNO(ENOENT),
+                                      "Failed to find module '%s'", module);
+
+        kmod_list_foreach(itr, modlist) {
+                _cleanup_(kmod_module_unrefp) struct kmod_module *mod = NULL;
+                int state, err;
+
+                mod = kmod_module_get_module(itr);
+                state = kmod_module_get_initstate(mod);
+
+                switch (state) {
+                case KMOD_MODULE_BUILTIN:
+                        log_full(verbose ? LOG_INFO : LOG_DEBUG,
+                                 "Module '%s' is built in", kmod_module_get_name(mod));
+                        break;
+
+                case KMOD_MODULE_LIVE:
+                        log_debug("Module '%s' is already loaded", kmod_module_get_name(mod));
+                        break;
+
+                default:
+                        err = kmod_module_probe_insert_module(mod, probe_flags,
+                                                              NULL, NULL, NULL, NULL);
+                        if (err == 0)
+                                log_full(verbose ? LOG_INFO : LOG_DEBUG,
+                                         "Inserted module '%s'", kmod_module_get_name(mod));
+                        else if (err == KMOD_PROBE_APPLY_BLACKLIST)
+                                log_full(verbose ? LOG_INFO : LOG_DEBUG,
+                                         "Module '%s' is deny-listed (by kmod)", kmod_module_get_name(mod));
+                        else {
+                                assert(err < 0);
+
+                                if (err == -EPERM) {
+                                        if (!denylist_parsed) {
+                                                r = proc_cmdline_parse(parse_proc_cmdline_item, &denylist, 0);
+                                                if (r < 0)
+                                                        log_full_errno(!verbose ? LOG_DEBUG : LOG_WARNING,
+                                                                       r,
+                                                                       "Failed to parse kernel command line, ignoring: %m");
+
+                                                denylist_parsed = true;
+                                        }
+                                        if (strv_contains(denylist, kmod_module_get_name(mod))) {
+                                                log_full(verbose ? LOG_INFO : LOG_DEBUG,
+                                                         "Module '%s' is deny-listed (by kernel)", kmod_module_get_name(mod));
+                                                continue;
+                                        }
+                                }
+
+                                log_full_errno(!verbose ? LOG_DEBUG :
+                                               err == -ENODEV ? LOG_NOTICE :
+                                               err == -ENOENT ? LOG_WARNING :
+                                                                LOG_ERR,
+                                               err,
+                                               "Failed to insert module '%s': %m",
+                                               kmod_module_get_name(mod));
+                                if (!IN_SET(err, -ENODEV, -ENOENT))
+                                        r = err;
+                        }
+                }
+        }
+
+        return r;
+}