From: Krzysztof Struczynski krzysztof.struczynski@huawei.com
hulk inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I49KW1 CVE: NA
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Add function that checks if the UID map is defined. It will be used by ima to check if ID remapping in subject-based rules is necessary.
Signed-off-by: Krzysztof Struczynski krzysztof.struczynski@huawei.com Reviewed-by: Zhang Tianxing zhangtianxing3@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- include/linux/user_namespace.h | 6 ++++++ kernel/user_namespace.c | 11 +++++++++++ 2 files changed, 17 insertions(+)
diff --git a/include/linux/user_namespace.h b/include/linux/user_namespace.h index 3eb64a50f248..6cb6a455e7aa 100644 --- a/include/linux/user_namespace.h +++ b/include/linux/user_namespace.h @@ -141,6 +141,7 @@ extern bool in_userns(const struct user_namespace *ancestor, const struct user_namespace *child); extern bool current_in_userns(const struct user_namespace *target_ns); struct ns_common *ns_get_owner(struct ns_common *ns); +extern bool userns_set_uidmap(const struct user_namespace *ns); #else
static inline struct user_namespace *get_user_ns(struct user_namespace *ns) @@ -185,6 +186,11 @@ static inline struct ns_common *ns_get_owner(struct ns_common *ns) { return ERR_PTR(-EPERM); } + +static inline bool userns_set_uidmap(const struct user_namespace *ns) +{ + return true; +} #endif
#endif /* _LINUX_USER_H */ diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c index ce396ea4de60..cf9b7019e8ef 100644 --- a/kernel/user_namespace.c +++ b/kernel/user_namespace.c @@ -1291,6 +1291,17 @@ bool current_in_userns(const struct user_namespace *target_ns) } EXPORT_SYMBOL(current_in_userns);
+bool userns_set_uidmap(const struct user_namespace *ns) +{ + bool mapping_defined; + + mutex_lock(&userns_state_mutex); + mapping_defined = ns->uid_map.nr_extents != 0; + mutex_unlock(&userns_state_mutex); + + return mapping_defined; +} + static inline struct user_namespace *to_user_ns(struct ns_common *ns) { return container_of(ns, struct user_namespace, ns);