path: root/ipc
diff options
authorChristian Brauner <>2020-05-05 16:04:30 +0200
committerChristian Brauner <>2020-05-09 13:57:12 +0200
commitf2a8d52e0a4db968c346c4332630a71cba377567 (patch)
treea5f50de02d68b5fd4599b5f12f584cf955edc5cf /ipc
parent0e698dfa282211e414076f9dc7e83c1c288314fd (diff)
nsproxy: add struct nsset
Add a simple struct nsset. It holds all necessary pieces to switch to a new set of namespaces without leaving a task in a half-switched state which we will make use of in the next patch. This patch switches the existing setns logic over without causing a change in setns() behavior. This brings setns() closer to how unshare() works(). The prepare_ns() function is responsible to prepare all necessary information. This has two reasons. First it minimizes dependencies between individual namespaces, i.e. all install handler can expect that all fields are properly initialized independent in what order they are called in. Second, this makes the code easier to maintain and easier to follow if it needs to be changed. The prepare_ns() helper will only be switched over to use a flags argument in the next patch. Here it will still use nstype as a simple integer argument which was argued would be clearer. I'm not particularly opinionated about this if it really helps or not. The struct nsset itself already contains the flags field since its name already indicates that it can contain information required by different namespaces. None of this should have functional consequences. Signed-off-by: Christian Brauner <> Reviewed-by: Serge Hallyn <> Cc: Eric W. Biederman <> Cc: Serge Hallyn <> Cc: Jann Horn <> Cc: Michael Kerrisk <> Cc: Aleksa Sarai <> Link:
Diffstat (limited to 'ipc')
1 files changed, 3 insertions, 4 deletions
diff --git a/ipc/namespace.c b/ipc/namespace.c
index b3ca1476ca51..fdc3b5f3f53a 100644
--- a/ipc/namespace.c
+++ b/ipc/namespace.c
@@ -177,15 +177,14 @@ static void ipcns_put(struct ns_common *ns)
return put_ipc_ns(to_ipc_ns(ns));
-static int ipcns_install(struct nsproxy *nsproxy, struct ns_common *new)
+static int ipcns_install(struct nsset *nsset, struct ns_common *new)
+ struct nsproxy *nsproxy = nsset->nsproxy;
struct ipc_namespace *ns = to_ipc_ns(new);
if (!ns_capable(ns->user_ns, CAP_SYS_ADMIN) ||
- !ns_capable(current_user_ns(), CAP_SYS_ADMIN))
+ !ns_capable(nsset->cred->user_ns, CAP_SYS_ADMIN))
return -EPERM;
- /* Ditch state from the old ipc namespace */
- exit_sem(current);
nsproxy->ipc_ns = get_ipc_ns(ns);
return 0;