Fix changing hash key after module is inserted in hash

The hash key is not copied so we can't change the string from:
	modname/modalias

	to:

	modname'\0'modalias

in order to setup mod->name and mod->alias.

Now what we do is:

1) if name is in the form 'modname/modalias', the final struct
   kmod_module will be:

   struct kmod_module {
           char *alias;------,
           char *name;-----, |
           char *hashkey;--|-|-,
   }                       | | |
   name <------------------' | |
   alias <-------------------' |
   hashkey <-------------------'

2) if name is in the simple form 'modname', then the final struct
   kmod_module will be:

   struct kmod_module {
           char *alias;------> NULL
           char *name;-----,
           char *hashkey;--|---,
   }                       |   |
   name <------------------*---'

libkmod/libkmod-module.c

@@ -45,6 +45,7 @@
  */
 struct kmod_module {
 	struct kmod_ctx *ctx;
+	char *hashkey;
 	char *name;
 	char *path;
 	struct kmod_list *dep;
@@ -231,7 +232,8 @@ KMOD_EXPORT int kmod_module_new_from_name(struct kmod_ctx *ctx,
 		return 0;
 	}
 
-	m = malloc(sizeof(*m) + namelen + 1);
+	namesep = strchr(name_norm, '/');
+	m = malloc(sizeof(*m) + (namesep == NULL ? 1 : 2) * namelen + 2);
 	if (m == NULL) {
 		free(m);
 		return -ENOMEM;
@@ -243,17 +245,19 @@ KMOD_EXPORT int kmod_module_new_from_name(struct kmod_ctx *ctx,
 	m->name = (char *)m + sizeof(*m);
 	memcpy(m->name, name_norm, namelen + 1);
 
-	m->refcount = 1;
+	if (namesep) {
+		size_t len = namesep - name_norm;
 
-	/* set alias later, so m->name is still modname/modalias */
-	kmod_pool_add_module(ctx, m);
-
-	namesep = strchr(m->name, '/');
-	if (namesep != NULL) {
-		*namesep = '\0';
-		m->alias = namesep + 1;
+		m->name[len] = '\0';
+		m->alias = m->name + len + 1;
+		m->hashkey = m->name + namelen + 1;
+		memcpy(m->hashkey, name_norm, namelen + 1);
+	} else {
+		m->hashkey = m->name;
 	}
 
+	m->refcount = 1;
+	kmod_pool_add_module(ctx, m, m->hashkey);
 	*mod = m;
 
 	return 0;
@@ -358,9 +362,10 @@ KMOD_EXPORT int kmod_module_new_from_path(struct kmod_ctx *ctx,
 	m->name = (char *)m + sizeof(*m);
 	memcpy(m->name, name, namelen);
 	m->path = abspath;
+	m->hashkey = m->name;
 	m->refcount = 1;
 
-	kmod_pool_add_module(ctx, m);
+	kmod_pool_add_module(ctx, m, m->hashkey);
 
 	*mod = m;
 

libkmod/libkmod-private.h

@@ -77,9 +77,9 @@ int kmod_lookup_alias_from_moddep_file(struct kmod_ctx *ctx, const char *name, s
 
 char *kmod_search_moddep(struct kmod_ctx *ctx, const char *name) __attribute__((nonnull(1,2)));
 
-struct kmod_module *kmod_pool_get_module(struct kmod_ctx *ctx, const char *name) __attribute__((nonnull(1,2)));
-void kmod_pool_add_module(struct kmod_ctx *ctx, struct kmod_module *mod) __attribute__((nonnull(1,2)));
-void kmod_pool_del_module(struct kmod_ctx *ctx, struct kmod_module *mod) __attribute__((nonnull(1,2)));
+struct kmod_module *kmod_pool_get_module(struct kmod_ctx *ctx, const char *key) __attribute__((nonnull(1,2)));
+void kmod_pool_add_module(struct kmod_ctx *ctx, struct kmod_module *mod, const char *key) __attribute__((nonnull(1,2, 3)));
+void kmod_pool_del_module(struct kmod_ctx *ctx, struct kmod_module *mod, const char *key) __attribute__((nonnull(1,2, 3)));
 
 const struct kmod_list *kmod_get_options(const struct kmod_ctx *ctx) __must_check __attribute__((nonnull(1)));
 const struct kmod_list *kmod_get_install_commands(const struct kmod_ctx *ctx) __must_check __attribute__((nonnull(1)));

libkmod/libkmod.c

@@ -342,33 +342,31 @@ KMOD_EXPORT void kmod_set_log_priority(struct kmod_ctx *ctx, int priority)
 }
 
 struct kmod_module *kmod_pool_get_module(struct kmod_ctx *ctx,
-							const char *name)
+							const char *key)
 {
 	struct kmod_module *mod;
 
-	mod = kmod_hash_find(ctx->modules_by_name, name);
+	mod = kmod_hash_find(ctx->modules_by_name, key);
 
-	DBG(ctx, "get module name='%s' found=%p\n", name, mod);
+	DBG(ctx, "get module name='%s' found=%p\n", key, mod);
 
 	return mod;
 }
 
-void kmod_pool_add_module(struct kmod_ctx *ctx, struct kmod_module *mod)
+void kmod_pool_add_module(struct kmod_ctx *ctx, struct kmod_module *mod,
+							const char *key)
 {
-	const char *name = kmod_module_get_name(mod);
+	DBG(ctx, "add %p key='%s'\n", mod, key);
 
-	DBG(ctx, "add %p name='%s'\n", mod, name);
-
-	kmod_hash_add(ctx->modules_by_name, name, mod);
+	kmod_hash_add(ctx->modules_by_name, key, mod);
 }
 
-void kmod_pool_del_module(struct kmod_ctx *ctx, struct kmod_module *mod)
+void kmod_pool_del_module(struct kmod_ctx *ctx, struct kmod_module *mod,
+							const char *key)
 {
-	const char *name = kmod_module_get_name(mod);
+	DBG(ctx, "del %p key='%s'\n", mod, key);
 
-	DBG(ctx, "del %p name='%s'\n", mod, name);
-
-	kmod_hash_del(ctx->modules_by_name, name);
+	kmod_hash_del(ctx->modules_by_name, key);
 }
 
 static int kmod_lookup_alias_from_alias_bin(struct kmod_ctx *ctx,