diff options
Diffstat (limited to 'SOURCES/tkg-unprivileged-CLONE_NEWUSER.patch')
| -rw-r--r-- | SOURCES/tkg-unprivileged-CLONE_NEWUSER.patch | 151 |
1 files changed, 0 insertions, 151 deletions
diff --git a/SOURCES/tkg-unprivileged-CLONE_NEWUSER.patch b/SOURCES/tkg-unprivileged-CLONE_NEWUSER.patch deleted file mode 100644 index 4d8146c..0000000 --- a/SOURCES/tkg-unprivileged-CLONE_NEWUSER.patch +++ /dev/null @@ -1,151 +0,0 @@ -From d50977b164e708bf523a35ef53315355528c3ca6 Mon Sep 17 00:00:00 2001 -From: "Jan Alexander Steffens (heftig)" <jan.steffens@gmail.com> -Date: Mon, 16 Sep 2019 04:53:20 +0200 -Subject: [PATCH] ZEN: Add sysctl and CONFIG to disallow unprivileged - CLONE_NEWUSER - -Our default behavior continues to match the vanilla kernel. ---- - include/linux/user_namespace.h | 4 ++++ - init/Kconfig | 16 ++++++++++++++++ - kernel/fork.c | 14 ++++++++++++++ - kernel/sysctl.c | 12 ++++++++++++ - kernel/user_namespace.c | 7 +++++++ - 5 files changed, 53 insertions(+) - -diff --git a/include/linux/user_namespace.h b/include/linux/user_namespace.h -index 45f09bec02c485..87b20e2ee27445 100644 ---- a/include/linux/user_namespace.h -+++ b/include/linux/user_namespace.h -@@ -148,6 +148,8 @@ static inline void set_userns_rlimit_max(struct user_namespace *ns, - - #ifdef CONFIG_USER_NS - -+extern int unprivileged_userns_clone; -+ - static inline struct user_namespace *get_user_ns(struct user_namespace *ns) - { - if (ns) -@@ -181,6 +183,8 @@ extern bool current_in_userns(const struct user_namespace *target_ns); - struct ns_common *ns_get_owner(struct ns_common *ns); - #else - -+#define unprivileged_userns_clone 0 -+ - static inline struct user_namespace *get_user_ns(struct user_namespace *ns) - { - return &init_user_ns; -diff --git a/init/Kconfig b/init/Kconfig -index 94125d3b6893c7..9f7139b536f638 100644 ---- a/init/Kconfig -+++ b/init/Kconfig -@@ -1247,6 +1247,22 @@ config USER_NS - - If unsure, say N. - -+config USER_NS_UNPRIVILEGED -+ bool "Allow unprivileged users to create namespaces" -+ default y -+ depends on USER_NS -+ help -+ When disabled, unprivileged users will not be able to create -+ new namespaces. Allowing users to create their own namespaces -+ has been part of several recent local privilege escalation -+ exploits, so if you need user namespaces but are -+ paranoid^Wsecurity-conscious you want to disable this. -+ -+ This setting can be overridden at runtime via the -+ kernel.unprivileged_userns_clone sysctl. -+ -+ If unsure, say Y. -+ - config PID_NS - bool "PID Namespaces" - default y -diff --git a/kernel/fork.c b/kernel/fork.c -index 08969f5aa38d59..ff601cb7a1fae0 100644 ---- a/kernel/fork.c -+++ b/kernel/fork.c -@@ -104,6 +104,10 @@ - #include <uapi/linux/pidfd.h> - #include <linux/pidfs.h> - -+#ifdef CONFIG_USER_NS -+#include <linux/user_namespace.h> -+#endif -+ - #include <asm/pgalloc.h> - #include <linux/uaccess.h> - #include <asm/mmu_context.h> -@@ -2008,6 +2012,10 @@ static __latent_entropy struct task_struct *copy_process( - if ((clone_flags & (CLONE_NEWUSER|CLONE_FS)) == (CLONE_NEWUSER|CLONE_FS)) - return ERR_PTR(-EINVAL); - -+ if ((clone_flags & CLONE_NEWUSER) && !unprivileged_userns_clone) -+ if (!capable(CAP_SYS_ADMIN)) -+ return ERR_PTR(-EPERM); -+ - /* - * Thread groups must share signals as well, and detached threads - * can only be started up within the thread group. -@@ -3166,6 +3174,12 @@ int ksys_unshare(unsigned long unshare_flags) - if (unshare_flags & CLONE_NEWNS) - unshare_flags |= CLONE_FS; - -+ if ((unshare_flags & CLONE_NEWUSER) && !unprivileged_userns_clone) { -+ err = -EPERM; -+ if (!capable(CAP_SYS_ADMIN)) -+ goto bad_unshare_out; -+ } -+ - err = check_unshare_flags(unshare_flags); - if (err) - goto bad_unshare_out; -diff --git a/kernel/sysctl.c b/kernel/sysctl.c -index c6d9dec11b749d..9a4514ad481b21 100644 ---- a/kernel/sysctl.c -+++ b/kernel/sysctl.c -@@ -81,6 +81,9 @@ - #ifdef CONFIG_RT_MUTEXES - #include <linux/rtmutex.h> - #endif -+#ifdef CONFIG_USER_NS -+#include <linux/user_namespace.h> -+#endif - - /* shared constants to be used in various sysctls */ - const int sysctl_vals[] = { 0, 1, 2, 3, 4, 100, 200, 1000, 3000, INT_MAX, 65535, -1 }; -@@ -1659,6 +1662,15 @@ static struct ctl_table kern_table[] = { - .mode = 0644, - .proc_handler = proc_dointvec, - }, -+#ifdef CONFIG_USER_NS -+ { -+ .procname = "unprivileged_userns_clone", -+ .data = &unprivileged_userns_clone, -+ .maxlen = sizeof(int), -+ .mode = 0644, -+ .proc_handler = proc_dointvec, -+ }, -+#endif - #ifdef CONFIG_PROC_SYSCTL - { - .procname = "tainted", -diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c -index 54211dbd516c57..16ca0c1516298d 100644 ---- a/kernel/user_namespace.c -+++ b/kernel/user_namespace.c -@@ -22,6 +22,13 @@ - #include <linux/bsearch.h> - #include <linux/sort.h> - -+/* sysctl */ -+#ifdef CONFIG_USER_NS_UNPRIVILEGED -+int unprivileged_userns_clone = 1; -+#else -+int unprivileged_userns_clone; -+#endif -+ - static struct kmem_cache *user_ns_cachep __ro_after_init; - static DEFINE_MUTEX(userns_state_mutex); - |