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Merge branch 'usermode-driver-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace into bpf-next

This commit is contained in:
Alexei Starovoitov 2020-07-14 12:18:01 -07:00
parent 11bb2f7a45 f06b71fe4d
commit ec2ffdf65f
15 changed files with 275 additions and 260 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
fs/exec.c
View File

@ -1818,13 +1818,14 @@ static int exec_binprm(struct linux_binprm *bprm)
/*
* sys_execve() executes a new program.
*/
static int __do_execve_file(int fd, struct filename *filename,
struct user_arg_ptr argv,
struct user_arg_ptr envp,
int flags, struct file *file)
static int do_execveat_common(int fd, struct filename *filename,
struct user_arg_ptr argv,
struct user_arg_ptr envp,
int flags)
{
char *pathbuf = NULL;
struct linux_binprm *bprm;
struct file *file;
struct files_struct *displaced;
int retval;
@ -1863,8 +1864,7 @@ static int __do_execve_file(int fd, struct filename *filename,
check_unsafe_exec(bprm);
current->in_execve = 1;
if (!file)
file = do_open_execat(fd, filename, flags);
file = do_open_execat(fd, filename, flags);
retval = PTR_ERR(file);
if (IS_ERR(file))
goto out_unmark;
@ -1872,9 +1872,7 @@ static int __do_execve_file(int fd, struct filename *filename,
sched_exec();
bprm->file = file;
if (!filename) {
bprm->filename = "none";
} else if (fd == AT_FDCWD || filename->name[0] == '/') {
if (fd == AT_FDCWD || filename->name[0] == '/') {
bprm->filename = filename->name;
} else {
if (filename->name[0] == '\0')
@ -1935,8 +1933,7 @@ static int __do_execve_file(int fd, struct filename *filename,
task_numa_free(current, false);
free_bprm(bprm);
kfree(pathbuf);
if (filename)
putname(filename);
putname(filename);
if (displaced)
put_files_struct(displaced);
return retval;
@ -1967,27 +1964,10 @@ out_files:
if (displaced)
reset_files_struct(displaced);
out_ret:
if (filename)
putname(filename);
putname(filename);
return retval;
}
static int do_execveat_common(int fd, struct filename *filename,
struct user_arg_ptr argv,
struct user_arg_ptr envp,
int flags)
{
return __do_execve_file(fd, filename, argv, envp, flags, NULL);
}
int do_execve_file(struct file *file, void *__argv, void *__envp)
{
struct user_arg_ptr argv = { .ptr.native = __argv };
struct user_arg_ptr envp = { .ptr.native = __envp };
return __do_execve_file(AT_FDCWD, NULL, argv, envp, 0, file);
}
int do_execve(struct filename *filename,
const char __user *const __user *__argv,
const char __user *const __user *__envp)

1
include/linux/binfmts.h
View File

@ -141,6 +141,5 @@ extern int do_execveat(int, struct filename *,
const char __user * const __user *,
const char __user * const __user *,
int);
int do_execve_file(struct file *file, void *__argv, void *__envp);
#endif /* _LINUX_BINFMTS_H */

7
include/linux/bpfilter.h
View File

@ -3,22 +3,23 @@
#define _LINUX_BPFILTER_H
#include <uapi/linux/bpfilter.h>
#include <linux/umh.h>
#include <linux/usermode_driver.h>
struct sock;
int bpfilter_ip_set_sockopt(struct sock *sk, int optname, char __user *optval,
unsigned int optlen);
int bpfilter_ip_get_sockopt(struct sock *sk, int optname, char __user *optval,
int __user *optlen);
void bpfilter_umh_cleanup(struct umd_info *info);
struct bpfilter_umh_ops {
struct umh_info info;
struct umd_info info;
/* since ip_getsockopt() can run in parallel, serialize access to umh */
struct mutex lock;
int (*sockopt)(struct sock *sk, int optname,
char __user *optval,
unsigned int optlen, bool is_set);
int (*start)(void);
bool stop;
};
extern struct bpfilter_umh_ops bpfilter_ops;
#endif

9
include/linux/sched.h
View File

@ -1510,7 +1510,6 @@ extern struct pid *cad_pid;
#define PF_KTHREAD 0x00200000 /* I am a kernel thread */
#define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */
#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
#define PF_UMH 0x02000000 /* I'm an Usermodehelper process */
#define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */
#define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
#define PF_MEMALLOC_NOCMA 0x10000000 /* All allocation request will have _GFP_MOVABLE cleared */
@ -2019,14 +2018,6 @@ static inline void rseq_execve(struct task_struct *t)
#endif
void __exit_umh(struct task_struct *tsk);
static inline void exit_umh(struct task_struct *tsk)
{
if (unlikely(tsk->flags & PF_UMH))
__exit_umh(tsk);
}
#ifdef CONFIG_DEBUG_RSEQ
void rseq_syscall(struct pt_regs *regs);

2
include/linux/sched/signal.h
View File

@ -674,6 +674,8 @@ static inline int thread_group_empty(struct task_struct *p)
#define delay_group_leader(p) \
(thread_group_leader(p) && !thread_group_empty(p))
extern bool thread_group_exited(struct pid *pid);
extern struct sighand_struct *__lock_task_sighand(struct task_struct *task,
unsigned long *flags);

15
include/linux/umh.h
View File

@ -22,10 +22,8 @@ struct subprocess_info {
const char *path;
char **argv;
char **envp;
struct file *file;
int wait;
int retval;
pid_t pid;
int (*init)(struct subprocess_info *info, struct cred *new);
void (*cleanup)(struct subprocess_info *info);
void *data;
@ -40,19 +38,6 @@ call_usermodehelper_setup(const char *path, char **argv, char **envp,
int (*init)(struct subprocess_info *info, struct cred *new),
void (*cleanup)(struct subprocess_info *), void *data);
struct subprocess_info *call_usermodehelper_setup_file(struct file *file,
int (*init)(struct subprocess_info *info, struct cred *new),
void (*cleanup)(struct subprocess_info *), void *data);
struct umh_info {
const char *cmdline;
struct file *pipe_to_umh;
struct file *pipe_from_umh;
struct list_head list;
void (*cleanup)(struct umh_info *info);
pid_t pid;
};
int fork_usermode_blob(void *data, size_t len, struct umh_info *info);
extern int
call_usermodehelper_exec(struct subprocess_info *info, int wait);

18
include/linux/usermode_driver.h Normal file
View File

@ -0,0 +1,18 @@
#ifndef __LINUX_USERMODE_DRIVER_H__
#define __LINUX_USERMODE_DRIVER_H__
#include <linux/umh.h>
#include <linux/path.h>
struct umd_info {
const char *driver_name;
struct file *pipe_to_umh;
struct file *pipe_from_umh;
struct path wd;
struct pid *tgid;
};
int umd_load_blob(struct umd_info *info, const void *data, size_t len);
int umd_unload_blob(struct umd_info *info);
int fork_usermode_driver(struct umd_info *info);
#endif /* __LINUX_USERMODE_DRIVER_H__ */

1
kernel/Makefile
View File

@ -12,6 +12,7 @@ obj-y = fork.o exec_domain.o panic.o \
notifier.o ksysfs.o cred.o reboot.o \
async.o range.o smpboot.o ucount.o
obj-$(CONFIG_BPFILTER) += usermode_driver.o
obj-$(CONFIG_MODULES) += kmod.o
obj-$(CONFIG_MULTIUSER) += groups.o

25
kernel/exit.c
View File

@ -804,7 +804,6 @@ void __noreturn do_exit(long code)
exit_task_namespaces(tsk);
exit_task_work(tsk);
exit_thread(tsk);
exit_umh(tsk);
/*
* Flush inherited counters to the parent - before the parent
@ -1711,6 +1710,30 @@ Efault:
}
#endif
/**
* thread_group_exited - check that a thread group has exited
* @pid: tgid of thread group to be checked.
*
* Test if the thread group represented by tgid has exited (all
* threads are zombies, dead or completely gone).
*
* Return: true if the thread group has exited. false otherwise.
*/
bool thread_group_exited(struct pid *pid)
{
struct task_struct *task;
bool exited;
rcu_read_lock();
task = pid_task(pid, PIDTYPE_PID);
exited = !task ||
(READ_ONCE(task->exit_state) && thread_group_empty(task));
rcu_read_unlock();
return exited;
}
EXPORT_SYMBOL(thread_group_exited);
__weak void abort(void)
{
BUG();

6
kernel/fork.c
View File

@ -1787,22 +1787,18 @@ static void pidfd_show_fdinfo(struct seq_file *m, struct file *f)
*/
static __poll_t pidfd_poll(struct file *file, struct poll_table_struct *pts)
{
struct task_struct *task;
struct pid *pid = file->private_data;
__poll_t poll_flags = 0;
poll_wait(file, &pid->wait_pidfd, pts);
rcu_read_lock();
task = pid_task(pid, PIDTYPE_PID);
/*
* Inform pollers only when the whole thread group exits.
* If the thread group leader exits before all other threads in the
* group, then poll(2) should block, similar to the wait(2) family.
*/
if (!task || (task->exit_state && thread_group_empty(task)))
if (thread_group_exited(pid))
poll_flags = EPOLLIN | EPOLLRDNORM;
rcu_read_unlock();
return poll_flags;
}

171
kernel/umh.c
View File

@ -26,8 +26,6 @@
#include <linux/ptrace.h>
#include <linux/async.h>
#include <linux/uaccess.h>
#include <linux/shmem_fs.h>
#include <linux/pipe_fs_i.h>
#include <trace/events/module.h>
@ -38,8 +36,6 @@ static kernel_cap_t usermodehelper_bset = CAP_FULL_SET;
static kernel_cap_t usermodehelper_inheritable = CAP_FULL_SET;
static DEFINE_SPINLOCK(umh_sysctl_lock);
static DECLARE_RWSEM(umhelper_sem);
static LIST_HEAD(umh_list);
static DEFINE_MUTEX(umh_list_lock);
static void call_usermodehelper_freeinfo(struct subprocess_info *info)
{
@ -102,16 +98,9 @@ static int call_usermodehelper_exec_async(void *data)
commit_creds(new);
sub_info->pid = task_pid_nr(current);
if (sub_info->file) {
retval = do_execve_file(sub_info->file,
sub_info->argv, sub_info->envp);
if (!retval)
current->flags |= PF_UMH;
} else
retval = do_execve(getname_kernel(sub_info->path),
(const char __user *const __user *)sub_info->argv,
(const char __user *const __user *)sub_info->envp);
retval = do_execve(getname_kernel(sub_info->path),
(const char __user *const __user *)sub_info->argv,
(const char __user *const __user *)sub_info->envp);
out:
sub_info->retval = retval;
/*
@ -405,140 +394,6 @@ struct subprocess_info *call_usermodehelper_setup(const char *path, char **argv,
}
EXPORT_SYMBOL(call_usermodehelper_setup);
struct subprocess_info *call_usermodehelper_setup_file(struct file *file,
int (*init)(struct subprocess_info *info, struct cred *new),
void (*cleanup)(struct subprocess_info *info), void *data)
{
struct subprocess_info *sub_info;
struct umh_info *info = data;
const char *cmdline = (info->cmdline) ? info->cmdline : "usermodehelper";
sub_info = kzalloc(sizeof(struct subprocess_info), GFP_KERNEL);
if (!sub_info)
return NULL;
sub_info->argv = argv_split(GFP_KERNEL, cmdline, NULL);
if (!sub_info->argv) {
kfree(sub_info);
return NULL;
}
INIT_WORK(&sub_info->work, call_usermodehelper_exec_work);
sub_info->path = "none";
sub_info->file = file;
sub_info->init = init;
sub_info->cleanup = cleanup;
sub_info->data = data;
return sub_info;
}
static int umh_pipe_setup(struct subprocess_info *info, struct cred *new)
{
struct umh_info *umh_info = info->data;
struct file *from_umh[2];
struct file *to_umh[2];
int err;
/* create pipe to send data to umh */
err = create_pipe_files(to_umh, 0);
if (err)
return err;
err = replace_fd(0, to_umh[0], 0);
fput(to_umh[0]);
if (err < 0) {
fput(to_umh[1]);
return err;
}
/* create pipe to receive data from umh */
err = create_pipe_files(from_umh, 0);
if (err) {
fput(to_umh[1]);
replace_fd(0, NULL, 0);
return err;
}
err = replace_fd(1, from_umh[1], 0);
fput(from_umh[1]);
if (err < 0) {
fput(to_umh[1]);
replace_fd(0, NULL, 0);
fput(from_umh[0]);
return err;
}
umh_info->pipe_to_umh = to_umh[1];
umh_info->pipe_from_umh = from_umh[0];
return 0;
}
static void umh_clean_and_save_pid(struct subprocess_info *info)
{
struct umh_info *umh_info = info->data;
/* cleanup if umh_pipe_setup() was successful but exec failed */
if (info->pid && info->retval) {
fput(umh_info->pipe_to_umh);
fput(umh_info->pipe_from_umh);
}
argv_free(info->argv);
umh_info->pid = info->pid;
}
/**
* fork_usermode_blob - fork a blob of bytes as a usermode process
* @data: a blob of bytes that can be do_execv-ed as a file
* @len: length of the blob
* @info: information about usermode process (shouldn't be NULL)
*
* If info->cmdline is set it will be used as command line for the
* user process, else "usermodehelper" is used.
*
* Returns either negative error or zero which indicates success
* in executing a blob of bytes as a usermode process. In such
* case 'struct umh_info *info' is populated with two pipes
* and a pid of the process. The caller is responsible for health
* check of the user process, killing it via pid, and closing the
* pipes when user process is no longer needed.
*/
int fork_usermode_blob(void *data, size_t len, struct umh_info *info)
{
struct subprocess_info *sub_info;
struct file *file;
ssize_t written;
loff_t pos = 0;
int err;
file = shmem_kernel_file_setup("", len, 0);
if (IS_ERR(file))
return PTR_ERR(file);
written = kernel_write(file, data, len, &pos);
if (written != len) {
err = written;
if (err >= 0)
err = -ENOMEM;
goto out;
}
err = -ENOMEM;
sub_info = call_usermodehelper_setup_file(file, umh_pipe_setup,
umh_clean_and_save_pid, info);
if (!sub_info)
goto out;
err = call_usermodehelper_exec(sub_info, UMH_WAIT_EXEC);
if (!err) {
mutex_lock(&umh_list_lock);
list_add(&info->list, &umh_list);
mutex_unlock(&umh_list_lock);
}
out:
fput(file);
return err;
}
EXPORT_SYMBOL_GPL(fork_usermode_blob);
/**
* call_usermodehelper_exec - start a usermode application
* @sub_info: information about the subprocessa
@ -700,26 +555,6 @@ static int proc_cap_handler(struct ctl_table *table, int write,
return 0;
}
void __exit_umh(struct task_struct *tsk)
{
struct umh_info *info;
pid_t pid = tsk->pid;
mutex_lock(&umh_list_lock);
list_for_each_entry(info, &umh_list, list) {
if (info->pid == pid) {
list_del(&info->list);
mutex_unlock(&umh_list_lock);
goto out;
}
}
mutex_unlock(&umh_list_lock);
return;
out:
if (info->cleanup)
info->cleanup(info);
}
struct ctl_table usermodehelper_table[] = {
{
.procname = "bset",

182
kernel/usermode_driver.c Normal file
View File

@ -0,0 +1,182 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
* umd - User mode driver support
*/
#include <linux/shmem_fs.h>
#include <linux/pipe_fs_i.h>
#include <linux/mount.h>
#include <linux/fs_struct.h>
#include <linux/task_work.h>
#include <linux/usermode_driver.h>
static struct vfsmount *blob_to_mnt(const void *data, size_t len, const char *name)
{
struct file_system_type *type;
struct vfsmount *mnt;
struct file *file;
ssize_t written;
loff_t pos = 0;
type = get_fs_type("tmpfs");
if (!type)
return ERR_PTR(-ENODEV);
mnt = kern_mount(type);
put_filesystem(type);
if (IS_ERR(mnt))
return mnt;
file = file_open_root(mnt->mnt_root, mnt, name, O_CREAT | O_WRONLY, 0700);
if (IS_ERR(file)) {
mntput(mnt);
return ERR_CAST(file);
}
written = kernel_write(file, data, len, &pos);
if (written != len) {
int err = written;
if (err >= 0)
err = -ENOMEM;
filp_close(file, NULL);
mntput(mnt);
return ERR_PTR(err);
}
fput(file);
/* Flush delayed fput so exec can open the file read-only */
flush_delayed_fput();
task_work_run();
return mnt;
}
/**
* umd_load_blob - Remember a blob of bytes for fork_usermode_driver
* @info: information about usermode driver
* @data: a blob of bytes that can be executed as a file
* @len: The lentgh of the blob
*
*/
int umd_load_blob(struct umd_info *info, const void *data, size_t len)
{
struct vfsmount *mnt;
if (WARN_ON_ONCE(info->wd.dentry || info->wd.mnt))
return -EBUSY;
mnt = blob_to_mnt(data, len, info->driver_name);
if (IS_ERR(mnt))
return PTR_ERR(mnt);
info->wd.mnt = mnt;
info->wd.dentry = mnt->mnt_root;
return 0;
}
EXPORT_SYMBOL_GPL(umd_load_blob);
/**
* umd_unload_blob - Disassociate @info from a previously loaded blob
* @info: information about usermode driver
*
*/
int umd_unload_blob(struct umd_info *info)
{
if (WARN_ON_ONCE(!info->wd.mnt ||
!info->wd.dentry ||
info->wd.mnt->mnt_root != info->wd.dentry))
return -EINVAL;
kern_unmount(info->wd.mnt);
info->wd.mnt = NULL;
info->wd.dentry = NULL;
return 0;
}
EXPORT_SYMBOL_GPL(umd_unload_blob);
static int umd_setup(struct subprocess_info *info, struct cred *new)
{
struct umd_info *umd_info = info->data;
struct file *from_umh[2];
struct file *to_umh[2];
int err;
/* create pipe to send data to umh */
err = create_pipe_files(to_umh, 0);
if (err)
return err;
err = replace_fd(0, to_umh[0], 0);
fput(to_umh[0]);
if (err < 0) {
fput(to_umh[1]);
return err;
}
/* create pipe to receive data from umh */
err = create_pipe_files(from_umh, 0);
if (err) {
fput(to_umh[1]);
replace_fd(0, NULL, 0);
return err;
}
err = replace_fd(1, from_umh[1], 0);
fput(from_umh[1]);
if (err < 0) {
fput(to_umh[1]);
replace_fd(0, NULL, 0);
fput(from_umh[0]);
return err;
}
set_fs_pwd(current->fs, &umd_info->wd);
umd_info->pipe_to_umh = to_umh[1];
umd_info->pipe_from_umh = from_umh[0];
umd_info->tgid = get_pid(task_tgid(current));
return 0;
}
static void umd_cleanup(struct subprocess_info *info)
{
struct umd_info *umd_info = info->data;
/* cleanup if umh_setup() was successful but exec failed */
if (info->retval) {
fput(umd_info->pipe_to_umh);
fput(umd_info->pipe_from_umh);
put_pid(umd_info->tgid);
umd_info->tgid = NULL;
}
}
/**
* fork_usermode_driver - fork a usermode driver
* @info: information about usermode driver (shouldn't be NULL)
*
* Returns either negative error or zero which indicates success in
* executing a usermode driver. In such case 'struct umd_info *info'
* is populated with two pipes and a tgid of the process. The caller is
* responsible for health check of the user process, killing it via
* tgid, and closing the pipes when user process is no longer needed.
*/
int fork_usermode_driver(struct umd_info *info)
{
struct subprocess_info *sub_info;
const char *argv[] = { info->driver_name, NULL };
int err;
if (WARN_ON_ONCE(info->tgid))
return -EBUSY;
err = -ENOMEM;
sub_info = call_usermodehelper_setup(info->driver_name,
(char **)argv, NULL, GFP_KERNEL,
umd_setup, umd_cleanup, info);
if (!sub_info)
goto out;
err = call_usermodehelper_exec(sub_info, UMH_WAIT_EXEC);
out:
return err;
}
EXPORT_SYMBOL_GPL(fork_usermode_driver);

38
net/bpfilter/bpfilter_kern.c
View File

@ -15,15 +15,13 @@ extern char bpfilter_umh_end;
static void shutdown_umh(void)
{
struct task_struct *tsk;
struct umd_info *info = &bpfilter_ops.info;
struct pid *tgid = info->tgid;
if (bpfilter_ops.stop)
return;
tsk = get_pid_task(find_vpid(bpfilter_ops.info.pid), PIDTYPE_PID);
if (tsk) {
send_sig(SIGKILL, tsk, 1);
put_task_struct(tsk);
if (tgid) {
kill_pid(tgid, SIGKILL, 1);
wait_event(tgid->wait_pidfd, thread_group_exited(tgid));
bpfilter_umh_cleanup(info);
}
}
@ -48,7 +46,7 @@ static int __bpfilter_process_sockopt(struct sock *sk, int optname,
req.cmd = optname;
req.addr = (long __force __user)optval;
req.len = optlen;
if (!bpfilter_ops.info.pid)
if (!bpfilter_ops.info.tgid)
goto out;
n = kernel_write(bpfilter_ops.info.pipe_to_umh, &req, sizeof(req),
&pos);
@ -77,13 +75,10 @@ static int start_umh(void)
int err;
/* fork usermode process */
err = fork_usermode_blob(&bpfilter_umh_start,
&bpfilter_umh_end - &bpfilter_umh_start,
&bpfilter_ops.info);
err = fork_usermode_driver(&bpfilter_ops.info);
if (err)
return err;
bpfilter_ops.stop = false;
pr_info("Loaded bpfilter_umh pid %d\n", bpfilter_ops.info.pid);
pr_info("Loaded bpfilter_umh pid %d\n", pid_nr(bpfilter_ops.info.tgid));
/* health check that usermode process started correctly */
if (__bpfilter_process_sockopt(NULL, 0, NULL, 0, 0) != 0) {
@ -98,18 +93,21 @@ static int __init load_umh(void)
{
int err;
err = umd_load_blob(&bpfilter_ops.info,
&bpfilter_umh_start,
&bpfilter_umh_end - &bpfilter_umh_start);
if (err)
return err;
mutex_lock(&bpfilter_ops.lock);
if (!bpfilter_ops.stop) {
err = -EFAULT;
goto out;
}
err = start_umh();
if (!err && IS_ENABLED(CONFIG_INET)) {
bpfilter_ops.sockopt = &__bpfilter_process_sockopt;
bpfilter_ops.start = &start_umh;
}
out:
mutex_unlock(&bpfilter_ops.lock);
if (err)
umd_unload_blob(&bpfilter_ops.info);
return err;
}
@ -122,6 +120,8 @@ static void __exit fini_umh(void)
bpfilter_ops.sockopt = NULL;
}
mutex_unlock(&bpfilter_ops.lock);
umd_unload_blob(&bpfilter_ops.info);
}
module_init(load_umh);
module_exit(fini_umh);

2
net/bpfilter/bpfilter_umh_blob.S
View File

@ -1,5 +1,5 @@
/* SPDX-License-Identifier: GPL-2.0 */
.section .rodata, "a"
.section .init.rodata, "a"
.global bpfilter_umh_start
bpfilter_umh_start:
.incbin "net/bpfilter/bpfilter_umh"

20
net/ipv4/bpfilter/sockopt.c
View File

@ -12,15 +12,14 @@
struct bpfilter_umh_ops bpfilter_ops;
EXPORT_SYMBOL_GPL(bpfilter_ops);
static void bpfilter_umh_cleanup(struct umh_info *info)
void bpfilter_umh_cleanup(struct umd_info *info)
{
mutex_lock(&bpfilter_ops.lock);
bpfilter_ops.stop = true;
fput(info->pipe_to_umh);
fput(info->pipe_from_umh);
info->pid = 0;
mutex_unlock(&bpfilter_ops.lock);
put_pid(info->tgid);
info->tgid = NULL;
}
EXPORT_SYMBOL_GPL(bpfilter_umh_cleanup);
static int bpfilter_mbox_request(struct sock *sk, int optname,
char __user *optval,
@ -38,7 +37,11 @@ static int bpfilter_mbox_request(struct sock *sk, int optname,
goto out;
}
}
if (bpfilter_ops.stop) {
if (bpfilter_ops.info.tgid &&
thread_group_exited(bpfilter_ops.info.tgid))
bpfilter_umh_cleanup(&bpfilter_ops.info);
if (!bpfilter_ops.info.tgid) {
err = bpfilter_ops.start();
if (err)
goto out;
@ -69,9 +72,8 @@ int bpfilter_ip_get_sockopt(struct sock *sk, int optname, char __user *optval,
static int __init bpfilter_sockopt_init(void)
{
mutex_init(&bpfilter_ops.lock);
bpfilter_ops.stop = true;
bpfilter_ops.info.cmdline = "bpfilter_umh";
bpfilter_ops.info.cleanup = &bpfilter_umh_cleanup;
bpfilter_ops.info.tgid = NULL;
bpfilter_ops.info.driver_name = "bpfilter_umh";
return 0;
}