diff options
| author | Eric W. Biederman <ebiederm@xmission.com> | 2012-07-26 12:13:20 +0400 |
|---|---|---|
| committer | Eric W. Biederman <ebiederm@xmission.com> | 2012-11-20 16:17:42 +0400 |
| commit | 142e1d1d5f088e7a38659daca6e84a730967774a (patch) | |
| tree | e2297a9a77f55bb15a566979c9c5658cff4737f8 | |
| parent | b33c77ef23dd3ec5692c9c0cc739a3f5f0f2baae (diff) | |
| download | linux-142e1d1d5f088e7a38659daca6e84a730967774a.tar.xz | |
userns: Allow unprivileged use of setns.
- Push the permission check from the core setns syscall into
the setns install methods where the user namespace of the
target namespace can be determined, and used in a ns_capable
call.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
| -rw-r--r-- | ipc/namespace.c | 6 | ||||
| -rw-r--r-- | kernel/nsproxy.c | 3 | ||||
| -rw-r--r-- | kernel/utsname.c | 7 | ||||
| -rw-r--r-- | net/core/net_namespace.c | 7 |
4 files changed, 17 insertions, 6 deletions
diff --git a/ipc/namespace.c b/ipc/namespace.c index f362298c5ce4..6ed33c05cb66 100644 --- a/ipc/namespace.c +++ b/ipc/namespace.c @@ -161,8 +161,12 @@ static void ipcns_put(void *ns) return put_ipc_ns(ns); } -static int ipcns_install(struct nsproxy *nsproxy, void *ns) +static int ipcns_install(struct nsproxy *nsproxy, void *new) { + struct ipc_namespace *ns = new; + if (!ns_capable(ns->user_ns, CAP_SYS_ADMIN)) + return -EPERM; + /* Ditch state from the old ipc namespace */ exit_sem(current); put_ipc_ns(nsproxy->ipc_ns); diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c index a214e0e9035f..4357a0a7d17d 100644 --- a/kernel/nsproxy.c +++ b/kernel/nsproxy.c @@ -242,9 +242,6 @@ SYSCALL_DEFINE2(setns, int, fd, int, nstype) struct file *file; int err; - if (!capable(CAP_SYS_ADMIN)) - return -EPERM; - file = proc_ns_fget(fd); if (IS_ERR(file)) return PTR_ERR(file); diff --git a/kernel/utsname.c b/kernel/utsname.c index 679d97a5d3fd..4a9362f9325d 100644 --- a/kernel/utsname.c +++ b/kernel/utsname.c @@ -102,8 +102,13 @@ static void utsns_put(void *ns) put_uts_ns(ns); } -static int utsns_install(struct nsproxy *nsproxy, void *ns) +static int utsns_install(struct nsproxy *nsproxy, void *new) { + struct uts_namespace *ns = new; + + if (!ns_capable(ns->user_ns, CAP_SYS_ADMIN)) + return -EPERM; + get_uts_ns(ns); put_uts_ns(nsproxy->uts_ns); nsproxy->uts_ns = ns; diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index 6456439cbbd9..ec2870b44c1f 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -630,8 +630,13 @@ static void netns_put(void *ns) static int netns_install(struct nsproxy *nsproxy, void *ns) { + struct net *net = ns; + + if (!ns_capable(net->user_ns, CAP_SYS_ADMIN)) + return -EPERM; + put_net(nsproxy->net_ns); - nsproxy->net_ns = get_net(ns); + nsproxy->net_ns = get_net(net); return 0; } |