[PATCH 26/32] nsfs: add current_in_namespace()
From: Christian Brauner <brauner@kernel.org>
Date: 2025-09-10 14:39:41
Also in:
cgroups, linux-block, linux-fsdevel, linux-kselftest, linux-nfs, lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
Add a helper to easily check whether a given namespace is the caller's current namespace. This is currently open-coded in a lot of places. Simply switch on the type and compare the results. Signed-off-by: Christian Brauner <brauner@kernel.org> --- include/linux/nsfs.h | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-)
diff --git a/include/linux/nsfs.h b/include/linux/nsfs.h
index fb84aa538091..e5a5fa83d36b 100644
--- a/include/linux/nsfs.h
+++ b/include/linux/nsfs.h@@ -5,6 +5,8 @@ #define _LINUX_NSFS_H #include <linux/ns_common.h> +#include <linux/cred.h> +#include <linux/pid_namespace.h> struct path; struct task_struct;
@@ -22,5 +24,17 @@ int ns_get_name(char *buf, size_t size, struct task_struct *task, const struct proc_ns_operations *ns_ops); void nsfs_init(void); -#endif /* _LINUX_NSFS_H */ +#define __current_namespace_from_type(__ns) \ + _Generic((__ns), \ + struct cgroup_namespace *: current->nsproxy->cgroup_ns, \ + struct ipc_namespace *: current->nsproxy->ipc_ns, \ + struct net *: current->nsproxy->net_ns, \ + struct pid_namespace *: task_active_pid_ns(current), \ + struct mnt_namespace *: current->nsproxy->mnt_ns, \ + struct time_namespace *: current->nsproxy->time_ns, \ + struct user_namespace *: current_user_ns(), \ + struct uts_namespace *: current->nsproxy->uts_ns) + +#define current_in_namespace(__ns) (__current_namespace_from_type(__ns) == __ns) +#endif /* _LINUX_NSFS_H */
--
2.47.3