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-rw-r--r--include/linux/usermode_driver.h2
-rw-r--r--kernel/exit.c3
-rw-r--r--kernel/usermode_driver.c15
-rw-r--r--net/bpfilter/bpfilter_kern.c13
-rw-r--r--net/ipv4/bpfilter/sockopt.c3
5 files changed, 20 insertions, 16 deletions
diff --git a/include/linux/usermode_driver.h b/include/linux/usermode_driver.h
index 97c919b7147c..45adbffb31d9 100644
--- a/include/linux/usermode_driver.h
+++ b/include/linux/usermode_driver.h
@@ -25,7 +25,7 @@ struct umd_info {
struct list_head list;
void (*cleanup)(struct umd_info *info);
struct path wd;
- pid_t pid;
+ 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);
diff --git a/kernel/exit.c b/kernel/exit.c
index a081deea52ca..d3294b611df1 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -805,7 +805,8 @@ void __noreturn do_exit(long code)
exit_task_namespaces(tsk);
exit_task_work(tsk);
exit_thread(tsk);
- exit_umh(tsk);
+ if (group_dead)
+ exit_umh(tsk);
/*
* Flush inherited counters to the parent - before the parent
diff --git a/kernel/usermode_driver.c b/kernel/usermode_driver.c
index a86798759f83..f77f8d7ce9e3 100644
--- a/kernel/usermode_driver.c
+++ b/kernel/usermode_driver.c
@@ -133,7 +133,7 @@ static int umd_setup(struct subprocess_info *info, struct cred *new)
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->pid = task_pid_nr(current);
+ umd_info->tgid = get_pid(task_tgid(current));
current->flags |= PF_UMH;
return 0;
}
@@ -146,6 +146,8 @@ static void umd_cleanup(struct subprocess_info *info)
if (info->retval) {
fput(umd_info->pipe_to_umh);
fput(umd_info->pipe_from_umh);
+ put_pid(umd_info->tgid);
+ umd_info->tgid = NULL;
}
}
@@ -155,9 +157,9 @@ static void umd_cleanup(struct subprocess_info *info)
*
* 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 pid of the process. The caller is
+ * 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
- * pid, and closing the pipes when user process is no longer needed.
+ * tgid, and closing the pipes when user process is no longer needed.
*/
int fork_usermode_driver(struct umd_info *info)
{
@@ -165,6 +167,9 @@ int fork_usermode_driver(struct umd_info *info)
char **argv = NULL;
int err;
+ if (WARN_ON_ONCE(info->tgid))
+ return -EBUSY;
+
err = -ENOMEM;
argv = argv_split(GFP_KERNEL, info->driver_name, NULL);
if (!argv)
@@ -192,11 +197,11 @@ EXPORT_SYMBOL_GPL(fork_usermode_driver);
void __exit_umh(struct task_struct *tsk)
{
struct umd_info *info;
- pid_t pid = tsk->pid;
+ struct pid *tgid = task_tgid(tsk);
mutex_lock(&umh_list_lock);
list_for_each_entry(info, &umh_list, list) {
- if (info->pid == pid) {
+ if (info->tgid == tgid) {
list_del(&info->list);
mutex_unlock(&umh_list_lock);
goto out;
diff --git a/net/bpfilter/bpfilter_kern.c b/net/bpfilter/bpfilter_kern.c
index 28883b00609d..08ea77c2b137 100644
--- a/net/bpfilter/bpfilter_kern.c
+++ b/net/bpfilter/bpfilter_kern.c
@@ -15,16 +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);
- }
+ kill_pid(tgid, SIGKILL, 1);
}
static void __stop_umh(void)
@@ -48,7 +45,7 @@ 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);
@@ -81,7 +78,7 @@ static int start_umh(void)
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) {
diff --git a/net/ipv4/bpfilter/sockopt.c b/net/ipv4/bpfilter/sockopt.c
index 5050de28333d..56cbc43145f6 100644
--- a/net/ipv4/bpfilter/sockopt.c
+++ b/net/ipv4/bpfilter/sockopt.c
@@ -18,7 +18,8 @@ static void bpfilter_umh_cleanup(struct umd_info *info)
bpfilter_ops.stop = true;
fput(info->pipe_to_umh);
fput(info->pipe_from_umh);
- info->pid = 0;
+ put_pid(info->tgid);
+ info->tgid = NULL;
mutex_unlock(&bpfilter_ops.lock);
}