#include <linux/syscalls.h>
#include <linux/unistd.h>
#include <linux/kmod.h>
-#include <linux/smp_lock.h>
#include <linux/slab.h>
#include <linux/mnt_namespace.h>
#include <linux/completion.h>
#include <linux/resource.h>
#include <asm/uaccess.h>
-extern int delete_module(const char *name, unsigned int flags);
-
extern int max_threads;
static struct workqueue_struct *khelper_wq;
modprobe_path is set via /proc/sys.
*/
char modprobe_path[KMOD_PATH_LEN] = "/sbin/modprobe";
-struct module_kobject kmod_mk;
/**
* request_module - try to load a kernel module
static atomic_t kmod_concurrent = ATOMIC_INIT(0);
#define MAX_KMOD_CONCURRENT 50 /* Completely arbitrary value - KAO */
static int kmod_loop_msg;
- char modalias[16 + MODULE_NAME_LEN] = "MODALIAS=";
- char *uevent_envp[2] = {
- modalias,
- NULL
- };
va_start(args, fmt);
ret = vsnprintf(module_name, MODULE_NAME_LEN, fmt, args);
if (ret >= MODULE_NAME_LEN)
return -ENAMETOOLONG;
- strcpy(&modalias[strlen("MODALIAS=")], module_name);
- kobject_uevent_env(&kmod_mk.kobj, KOBJ_CHANGE, uevent_envp);
-
- if (modprobe_path[0] == '\0')
- goto out;
-
/* If modprobe needs a service that is in a module, we get a recursive
* loop. Limit the number of running kmod threads to max_threads/2 or
* MAX_KMOD_CONCURRENT, whichever is the smaller. A cleaner method
ret = call_usermodehelper(modprobe_path, argv, envp, 1);
atomic_dec(&kmod_concurrent);
-out:
return ret;
}
EXPORT_SYMBOL(request_module);
-
-static ssize_t store_mod_request(struct module_attribute *mattr,
- struct module *mod,
- const char *buffer, size_t count)
-{
- char name[MODULE_NAME_LEN];
- int ret;
-
- if (count < 1 || count+1 > MODULE_NAME_LEN)
- return -EINVAL;
- memcpy(name, buffer, count);
- name[count] = '\0';
- if (name[count-1] == '\n')
- name[count-1] = '\0';
-
- ret = request_module(name);
- if (ret < 0)
- return ret;
- return count;
-}
-
-static struct module_attribute mod_request = {
- .attr = { .name = "mod_request", .mode = S_IWUSR, .owner = THIS_MODULE },
- .store = store_mod_request,
-};
-
-#ifdef CONFIG_MODULE_UNLOAD
-static ssize_t store_mod_unload(struct module_attribute *mattr,
- struct module *mod,
- const char *buffer, size_t count)
-{
- char name[MODULE_NAME_LEN];
- int ret;
-
- if (count < 1 || count+1 > MODULE_NAME_LEN)
- return -EINVAL;
- memcpy(name, buffer, count);
- name[count] = '\0';
- if (name[count-1] == '\n')
- name[count-1] = '\0';
-
- ret = delete_module(name, O_NONBLOCK);
- if (ret < 0)
- return ret;
- return count;
-}
-
-static struct module_attribute mod_unload = {
- .attr = { .name = "mod_unload", .mode = S_IWUSR, .owner = THIS_MODULE },
- .store = store_mod_unload,
-};
-#endif
-
-static ssize_t show_mod_request_helper(struct module_attribute *mattr,
- struct module *mod,
- char *buffer)
-{
- return sprintf(buffer, "%s\n", modprobe_path);
-}
-
-static ssize_t store_mod_request_helper(struct module_attribute *mattr,
- struct module *mod,
- const char *buffer, size_t count)
-{
- if (count < 1 || count+1 > KMOD_PATH_LEN)
- return -EINVAL;
- memcpy(modprobe_path, buffer, count);
- modprobe_path[count] = '\0';
- if (modprobe_path[count-1] == '\n')
- modprobe_path[count-1] = '\0';
- return count;
-}
-
-static struct module_attribute mod_request_helper = {
- .attr = {
- .name = "mod_request_helper",
- .mode = S_IWUSR | S_IRUGO,
- .owner = THIS_MODULE
- },
- .show = show_mod_request_helper,
- .store = store_mod_request_helper,
-};
-
-void __init kmod_sysfs_init(void)
-{
- int ret;
-
- kmod_mk.mod = THIS_MODULE;
- kobj_set_kset_s(&kmod_mk, module_subsys);
- kobject_set_name(&kmod_mk.kobj, "kmod");
- kobject_init(&kmod_mk.kobj);
- ret = kobject_add(&kmod_mk.kobj);
- if (ret < 0)
- goto out;
-
- ret = sysfs_create_file(&kmod_mk.kobj, &mod_request_helper.attr);
- ret = sysfs_create_file(&kmod_mk.kobj, &mod_request.attr);
-#ifdef CONFIG_MODULE_UNLOAD
- ret = sysfs_create_file(&kmod_mk.kobj, &mod_unload.attr);
-#endif
-
- kobject_uevent(&kmod_mk.kobj, KOBJ_ADD);
-out:
- return;
-}
#endif /* CONFIG_KMOD */
struct subprocess_info {
/* Unblock all signals and set the session keyring. */
new_session = key_get(sub_info->ring);
- flush_signals(current);
spin_lock_irq(¤t->sighand->siglock);
old_session = __install_session_keyring(current, new_session);
flush_signal_handlers(current, 1);
/* We can run anywhere, unlike our parent keventd(). */
set_cpus_allowed(current, CPU_MASK_ALL);
+ /*
+ * Our parent is keventd, which runs with elevated scheduling priority.
+ * Avoid propagating that into the userspace child.
+ */
+ set_user_nice(current, 0);
+
retval = -EPERM;
if (current->fs->root)
retval = kernel_execve(sub_info->path,
{
struct subprocess_info *sub_info = data;
pid_t pid;
- struct k_sigaction sa;
/* Install a handler: if SIGCLD isn't handled sys_wait4 won't
* populate the status, but will return -ECHILD. */
- sa.sa.sa_handler = SIG_IGN;
- sa.sa.sa_flags = 0;
- siginitset(&sa.sa.sa_mask, sigmask(SIGCHLD));
- do_sigaction(SIGCHLD, &sa, NULL);
allow_signal(SIGCHLD);
pid = kernel_thread(____call_usermodehelper, sub_info, SIGCHLD);
git.samba.org / sfrench / cifs-2.6.git / blobdiff