[PATCH v2] namespace: make timens_on_fork() return nothing

[PATCH v2] namespace: make timens_on_fork() return nothing

[Hui Su]

timens_on_fork() always return 0, and maybe not
need to judge the return value in copy_namespaces().

So make timens_on_fork() return nothing and do not
judge its return val in copy_namespaces().

Signed-off-by: Hui Su <sh_def@163.com>
---
 include/linux/time_namespace.h | 6 +++---
 kernel/nsproxy.c               | 7 +------
 kernel/time/namespace.c        | 6 ++----
 3 files changed, 6 insertions(+), 13 deletions(-)

diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h
index 5b6031385db0..74a88ce0cd3c 100644
--- a/include/linux/time_namespace.h
+++ b/include/linux/time_namespace.h
@@ -45,7 +45,7 @@ struct time_namespace *copy_time_ns(unsigned long flags,
 				    struct user_namespace *user_ns,
 				    struct time_namespace *old_ns);
 void free_time_ns(struct kref *kref);
-int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk);
+void timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk);
 struct vdso_data *arch_get_vdso_data(void *vvar_page);
 
 static inline void put_time_ns(struct time_namespace *ns)
@@ -122,10 +122,10 @@ struct time_namespace *copy_time_ns(unsigned long flags,
 	return old_ns;
 }
 
-static inline int timens_on_fork(struct nsproxy *nsproxy,
+static inline void timens_on_fork(struct nsproxy *nsproxy,
 				 struct task_struct *tsk)
 {
-	return 0;
+	return;
 }
 
 static inline void timens_add_monotonic(struct timespec64 *ts) { }
diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c
index 12dd41b39a7f..e2e6c5dc433f 100644
--- a/kernel/nsproxy.c
+++ b/kernel/nsproxy.c
@@ -153,7 +153,6 @@ int copy_namespaces(unsigned long flags, struct task_struct *tsk)
 	struct nsproxy *old_ns = tsk->nsproxy;
 	struct user_namespace *user_ns = task_cred_xxx(tsk, user_ns);
 	struct nsproxy *new_ns;
-	int ret;
 
 	if (likely(!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC |
 			      CLONE_NEWPID | CLONE_NEWNET |
@@ -180,11 +179,7 @@ int copy_namespaces(unsigned long flags, struct task_struct *tsk)
 	if (IS_ERR(new_ns))
 		return  PTR_ERR(new_ns);
 
-	ret = timens_on_fork(new_ns, tsk);
-	if (ret) {
-		free_nsproxy(new_ns);
-		return ret;
-	}
+	timens_on_fork(new_ns, tsk);
 
 	tsk->nsproxy = new_ns;
 	return 0;
diff --git a/kernel/time/namespace.c b/kernel/time/namespace.c
index afc65e6be33e..e0f9509b17c3 100644
--- a/kernel/time/namespace.c
+++ b/kernel/time/namespace.c
@@ -308,22 +308,20 @@ static int timens_install(struct nsset *nsset, struct ns_common *new)
 	return 0;
 }
 
-int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk)
+void timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk)
 {
 	struct ns_common *nsc = &nsproxy->time_ns_for_children->ns;
 	struct time_namespace *ns = to_time_ns(nsc);
 
 	/* create_new_namespaces() already incremented the ref counter */
 	if (nsproxy->time_ns == nsproxy->time_ns_for_children)
-		return 0;
+		return;
 
 	get_time_ns(ns);
 	put_time_ns(nsproxy->time_ns);
 	nsproxy->time_ns = ns;
 
 	timens_commit(tsk, ns);
-
-	return 0;
 }
 
 static struct user_namespace *timens_owner(struct ns_common *ns)
-- 
2.29.0

Re: [PATCH v2] namespace: make timens_on_fork() return nothing

[Christian Brauner]

On Wed, Nov 18, 2020 at 12:17:50AM +0800, Hui Su wrote:
> timens_on_fork() always return 0, and maybe not
> need to judge the return value in copy_namespaces().
> 
> So make timens_on_fork() return nothing and do not
> judge its return val in copy_namespaces().
> 
> Signed-off-by: Hui Su <sh_def@163.com>
> ---

Acked-by: Christian Brauner <christian.brauner@ubuntu.com>

Applied to:
https://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux.git/log/?h=time_namespace

on top of the other timens patches I've queued up already.

Thanks!
Christian