From add005357d535681c7075ced8eec2b6e61b43728 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Tue, 1 Nov 2016 20:25:19 -0600 Subject: core: add new RestrictNamespaces= unit file setting This new setting permits restricting whether namespaces may be created and managed by processes started by a unit. It installs a seccomp filter blocking certain invocations of unshare(), clone() and setns(). RestrictNamespaces=no is the default, and does not restrict namespaces in any way. RestrictNamespaces=yes takes away the ability to create or manage any kind of namspace. "RestrictNamespaces=mnt ipc" restricts the creation of namespaces so that only mount and IPC namespaces may be created/managed, but no other kind of namespaces. This setting should be improve security quite a bit as in particular user namespacing was a major source of CVEs in the kernel in the past, and is accessible to unprivileged processes. With this setting the entire attack surface may be removed for system services that do not make use of namespaces. --- src/core/load-fragment.h | 1 + 1 file changed, 1 insertion(+) (limited to 'src/core/load-fragment.h') diff --git a/src/core/load-fragment.h b/src/core/load-fragment.h index c05f205c37..1cff815a50 100644 --- a/src/core/load-fragment.h +++ b/src/core/load-fragment.h @@ -116,6 +116,7 @@ int config_parse_fdname(const char *unit, const char *filename, unsigned line, c int config_parse_sec_fix_0(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata); int config_parse_user_group(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata); int config_parse_user_group_strv(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata); +int config_parse_restrict_namespaces(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata); /* gperf prototypes */ const struct ConfigPerfItem* load_fragment_gperf_lookup(const char *key, unsigned length); -- cgit v1.2.3-54-g00ecf