qemu/util/module.c
Bruce Rogers 267514b33f module: increase dirs array size by one
With the module upgrades code change, the statically sized dirs array
can now overflow. Increase it's size by one, according to the new
maximum possible usage.

Fixes: bd83c861c0 ("modules: load modules from versioned /var/run dir")
Signed-off-by: Bruce Rogers <brogers@suse.com>
Message-Id: <20200411010746.472295-1-brogers@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-13 02:56:18 -04:00

248 lines
5.6 KiB
C

/*
* QEMU Module Infrastructure
*
* Copyright IBM, Corp. 2009
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
* Contributions after 2012-01-13 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
*/
#include "qemu/osdep.h"
#ifdef CONFIG_MODULES
#include <gmodule.h>
#endif
#include "qemu/queue.h"
#include "qemu/module.h"
#ifdef CONFIG_MODULE_UPGRADES
#include "qemu-version.h"
#endif
typedef struct ModuleEntry
{
void (*init)(void);
QTAILQ_ENTRY(ModuleEntry) node;
module_init_type type;
} ModuleEntry;
typedef QTAILQ_HEAD(, ModuleEntry) ModuleTypeList;
static ModuleTypeList init_type_list[MODULE_INIT_MAX];
static bool modules_init_done[MODULE_INIT_MAX];
static ModuleTypeList dso_init_list;
static void init_lists(void)
{
static int inited;
int i;
if (inited) {
return;
}
for (i = 0; i < MODULE_INIT_MAX; i++) {
QTAILQ_INIT(&init_type_list[i]);
}
QTAILQ_INIT(&dso_init_list);
inited = 1;
}
static ModuleTypeList *find_type(module_init_type type)
{
init_lists();
return &init_type_list[type];
}
void register_module_init(void (*fn)(void), module_init_type type)
{
ModuleEntry *e;
ModuleTypeList *l;
e = g_malloc0(sizeof(*e));
e->init = fn;
e->type = type;
l = find_type(type);
QTAILQ_INSERT_TAIL(l, e, node);
}
void register_dso_module_init(void (*fn)(void), module_init_type type)
{
ModuleEntry *e;
init_lists();
e = g_malloc0(sizeof(*e));
e->init = fn;
e->type = type;
QTAILQ_INSERT_TAIL(&dso_init_list, e, node);
}
void module_call_init(module_init_type type)
{
ModuleTypeList *l;
ModuleEntry *e;
if (modules_init_done[type]) {
return;
}
l = find_type(type);
QTAILQ_FOREACH(e, l, node) {
e->init();
}
modules_init_done[type] = true;
}
#ifdef CONFIG_MODULES
static int module_load_file(const char *fname)
{
GModule *g_module;
void (*sym)(void);
const char *dsosuf = HOST_DSOSUF;
int len = strlen(fname);
int suf_len = strlen(dsosuf);
ModuleEntry *e, *next;
int ret;
if (len <= suf_len || strcmp(&fname[len - suf_len], dsosuf)) {
/* wrong suffix */
ret = -EINVAL;
goto out;
}
if (access(fname, F_OK)) {
ret = -ENOENT;
goto out;
}
assert(QTAILQ_EMPTY(&dso_init_list));
g_module = g_module_open(fname, G_MODULE_BIND_LAZY | G_MODULE_BIND_LOCAL);
if (!g_module) {
fprintf(stderr, "Failed to open module: %s\n",
g_module_error());
ret = -EINVAL;
goto out;
}
if (!g_module_symbol(g_module, DSO_STAMP_FUN_STR, (gpointer *)&sym)) {
fprintf(stderr, "Failed to initialize module: %s\n",
fname);
/* Print some info if this is a QEMU module (but from different build),
* this will make debugging user problems easier. */
if (g_module_symbol(g_module, "qemu_module_dummy", (gpointer *)&sym)) {
fprintf(stderr,
"Note: only modules from the same build can be loaded.\n");
}
g_module_close(g_module);
ret = -EINVAL;
} else {
QTAILQ_FOREACH(e, &dso_init_list, node) {
e->init();
register_module_init(e->init, e->type);
}
ret = 0;
}
QTAILQ_FOREACH_SAFE(e, &dso_init_list, node, next) {
QTAILQ_REMOVE(&dso_init_list, e, node);
g_free(e);
}
out:
return ret;
}
#endif
bool module_load_one(const char *prefix, const char *lib_name)
{
bool success = false;
#ifdef CONFIG_MODULES
char *fname = NULL;
char *exec_dir;
#ifdef CONFIG_MODULE_UPGRADES
char *version_dir;
#endif
const char *search_dir;
char *dirs[5];
char *module_name;
int i = 0, n_dirs = 0;
int ret;
static GHashTable *loaded_modules;
if (!g_module_supported()) {
fprintf(stderr, "Module is not supported by system.\n");
return false;
}
if (!loaded_modules) {
loaded_modules = g_hash_table_new(g_str_hash, g_str_equal);
}
module_name = g_strdup_printf("%s%s", prefix, lib_name);
if (!g_hash_table_add(loaded_modules, module_name)) {
g_free(module_name);
return true;
}
exec_dir = qemu_get_exec_dir();
search_dir = getenv("QEMU_MODULE_DIR");
if (search_dir != NULL) {
dirs[n_dirs++] = g_strdup_printf("%s", search_dir);
}
dirs[n_dirs++] = g_strdup_printf("%s", CONFIG_QEMU_MODDIR);
dirs[n_dirs++] = g_strdup_printf("%s/..", exec_dir ? : "");
dirs[n_dirs++] = g_strdup_printf("%s", exec_dir ? : "");
#ifdef CONFIG_MODULE_UPGRADES
version_dir = g_strcanon(g_strdup(QEMU_PKGVERSION),
G_CSET_A_2_Z G_CSET_a_2_z G_CSET_DIGITS "+-.~",
'_');
dirs[n_dirs++] = g_strdup_printf("/var/run/qemu/%s", version_dir);
#endif
assert(n_dirs <= ARRAY_SIZE(dirs));
g_free(exec_dir);
exec_dir = NULL;
for (i = 0; i < n_dirs; i++) {
fname = g_strdup_printf("%s/%s%s",
dirs[i], module_name, HOST_DSOSUF);
ret = module_load_file(fname);
g_free(fname);
fname = NULL;
/* Try loading until loaded a module file */
if (!ret) {
success = true;
break;
}
}
if (!success) {
g_hash_table_remove(loaded_modules, module_name);
g_free(module_name);
}
for (i = 0; i < n_dirs; i++) {
g_free(dirs[i]);
}
#endif
return success;
}