diff options
| -rw-r--r-- | include/linux/user_namespace.h | 1 | ||||
| -rw-r--r-- | include/linux/utsname.h | 1 | ||||
| -rw-r--r-- | kernel/ucount.c | 1 | ||||
| -rw-r--r-- | kernel/utsname.c | 34 |
4 files changed, 32 insertions, 5 deletions
diff --git a/include/linux/user_namespace.h b/include/linux/user_namespace.h index 9ee94827728d..f9df7dd2609a 100644 --- a/include/linux/user_namespace.h +++ b/include/linux/user_namespace.h @@ -27,6 +27,7 @@ struct ucounts; enum ucount_type { UCOUNT_USER_NAMESPACES, UCOUNT_PID_NAMESPACES, + UCOUNT_UTS_NAMESPACES, UCOUNT_COUNTS, }; diff --git a/include/linux/utsname.h b/include/linux/utsname.h index 5093f58ae192..60f0bb83b313 100644 --- a/include/linux/utsname.h +++ b/include/linux/utsname.h @@ -24,6 +24,7 @@ struct uts_namespace { struct kref kref; struct new_utsname name; struct user_namespace *user_ns; + struct ucounts *ucounts; struct ns_common ns; }; extern struct uts_namespace init_uts_ns; diff --git a/kernel/ucount.c b/kernel/ucount.c index 66eca94e4ada..866850e2eb92 100644 --- a/kernel/ucount.c +++ b/kernel/ucount.c @@ -69,6 +69,7 @@ static int int_max = INT_MAX; static struct ctl_table user_table[] = { UCOUNT_ENTRY("max_user_namespaces"), UCOUNT_ENTRY("max_pid_namespaces"), + UCOUNT_ENTRY("max_uts_namespaces"), { } }; #endif /* CONFIG_SYSCTL */ diff --git a/kernel/utsname.c b/kernel/utsname.c index 831ea7108232..f3b0bb4ac3ba 100644 --- a/kernel/utsname.c +++ b/kernel/utsname.c @@ -17,6 +17,16 @@ #include <linux/user_namespace.h> #include <linux/proc_ns.h> +static struct ucounts *inc_uts_namespaces(struct user_namespace *ns) +{ + return inc_ucount(ns, current_euid(), UCOUNT_UTS_NAMESPACES); +} + +static void dec_uts_namespaces(struct ucounts *ucounts) +{ + dec_ucount(ucounts, UCOUNT_UTS_NAMESPACES); +} + static struct uts_namespace *create_uts_ns(void) { struct uts_namespace *uts_ns; @@ -36,18 +46,24 @@ static struct uts_namespace *clone_uts_ns(struct user_namespace *user_ns, struct uts_namespace *old_ns) { struct uts_namespace *ns; + struct ucounts *ucounts; int err; + err = -ENFILE; + ucounts = inc_uts_namespaces(user_ns); + if (!ucounts) + goto fail; + + err = -ENOMEM; ns = create_uts_ns(); if (!ns) - return ERR_PTR(-ENOMEM); + goto fail_dec; err = ns_alloc_inum(&ns->ns); - if (err) { - kfree(ns); - return ERR_PTR(err); - } + if (err) + goto fail_free; + ns->ucounts = ucounts; ns->ns.ops = &utsns_operations; down_read(&uts_sem); @@ -55,6 +71,13 @@ static struct uts_namespace *clone_uts_ns(struct user_namespace *user_ns, ns->user_ns = get_user_ns(user_ns); up_read(&uts_sem); return ns; + +fail_free: + kfree(ns); +fail_dec: + dec_uts_namespaces(ucounts); +fail: + return ERR_PTR(err); } /* @@ -85,6 +108,7 @@ void free_uts_ns(struct kref *kref) struct uts_namespace *ns; ns = container_of(kref, struct uts_namespace, kref); + dec_uts_namespaces(ns->ucounts); put_user_ns(ns->user_ns); ns_free_inum(&ns->ns); kfree(ns); |