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Diffstat (limited to 'sys-kernel/linux-image-redcore/files/6.10-ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch')
-rw-r--r--sys-kernel/linux-image-redcore/files/6.10-ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch131
1 files changed, 131 insertions, 0 deletions
diff --git a/sys-kernel/linux-image-redcore/files/6.10-ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch b/sys-kernel/linux-image-redcore/files/6.10-ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch
new file mode 100644
index 00000000..09d6a2c0
--- /dev/null
+++ b/sys-kernel/linux-image-redcore/files/6.10-ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch
@@ -0,0 +1,131 @@
+diff -Nur a/include/linux/user_namespace.h b/include/linux/user_namespace.h
+--- a/include/linux/user_namespace.h 2024-02-23 08:51:59.000000000 +0000
++++ b/include/linux/user_namespace.h 2024-02-24 11:24:37.945502209 +0000
+@@ -156,6 +156,8 @@
+
+ #ifdef CONFIG_USER_NS
+
++extern int unprivileged_userns_clone;
++
+ static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
+ {
+ if (ns)
+@@ -189,6 +191,8 @@
+ 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 -Nur a/init/Kconfig b/init/Kconfig
+--- a/init/Kconfig 2024-02-23 08:51:59.000000000 +0000
++++ b/init/Kconfig 2024-02-24 11:24:37.945502209 +0000
+@@ -1235,6 +1235,22 @@
+
+ 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 -Nur a/kernel/fork.c b/kernel/fork.c
+--- a/kernel/fork.c 2024-02-23 08:51:59.000000000 +0000
++++ b/kernel/fork.c 2024-02-24 11:24:37.946502209 +0000
+@@ -100,6 +100,10 @@
+ #include <linux/user_events.h>
+ #include <linux/iommu.h>
+
++#ifdef CONFIG_USER_NS
++#include <linux/user_namespace.h>
++#endif
++
+ #include <asm/pgalloc.h>
+ #include <linux/uaccess.h>
+ #include <asm/mmu_context.h>
+@@ -2265,6 +2269,10 @@
+ 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.
+@@ -3411,6 +3419,12 @@
+ 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 -Nur a/kernel/sysctl.c b/kernel/sysctl.c
+--- a/kernel/sysctl.c 2024-02-23 08:51:59.000000000 +0000
++++ b/kernel/sysctl.c 2024-02-24 11:24:37.946502209 +0000
+@@ -80,6 +80,9 @@
+ #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 };
+@@ -1623,6 +1626,15 @@
+ .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 -Nur a/kernel/user_namespace.c b/kernel/user_namespace.c
+--- a/kernel/user_namespace.c 2024-02-23 08:51:59.000000000 +0000
++++ b/kernel/user_namespace.c 2024-02-24 11:40:48.120538387 +0000
+@@ -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);
+