diff options
Diffstat (limited to '0001-add-sysctl-to-disallow-unprivileged-CLONE_NEWUSER-by.patch')
| -rw-r--r-- | 0001-add-sysctl-to-disallow-unprivileged-CLONE_NEWUSER-by.patch | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/0001-add-sysctl-to-disallow-unprivileged-CLONE_NEWUSER-by.patch b/0001-add-sysctl-to-disallow-unprivileged-CLONE_NEWUSER-by.patch new file mode 100644 index 000000000000..0249a08eb723 --- /dev/null +++ b/0001-add-sysctl-to-disallow-unprivileged-CLONE_NEWUSER-by.patch @@ -0,0 +1,102 @@ +From 66a37293bf1ec5bf9d22ede72818099f2c72fbc1 Mon Sep 17 00:00:00 2001 +From: Serge Hallyn <serge.hallyn@canonical.com> +Date: Fri, 31 May 2013 19:12:12 +0100 +Subject: [PATCH 1/5] add sysctl to disallow unprivileged CLONE_NEWUSER by + default + +Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com> +[bwh: Remove unneeded binary sysctl bits] +Signed-off-by: Daniel Micay <danielmicay@gmail.com> +--- + kernel/fork.c | 15 +++++++++++++++ + kernel/sysctl.c | 12 ++++++++++++ + kernel/user_namespace.c | 3 +++ + 3 files changed, 30 insertions(+) + +diff --git a/kernel/fork.c b/kernel/fork.c +index 5ad558e6f8fe..767485c6f7cc 100644 +--- a/kernel/fork.c ++++ b/kernel/fork.c +@@ -103,6 +103,11 @@ + + #define CREATE_TRACE_POINTS + #include <trace/events/task.h> ++#ifdef CONFIG_USER_NS ++extern int unprivileged_userns_clone; ++#else ++#define unprivileged_userns_clone 0 ++#endif + + /* + * Minimum number of threads to boot the kernel +@@ -1600,6 +1605,10 @@ 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. +@@ -2394,6 +2403,12 @@ 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 6a78cf70761d..35a1d24282f4 100644 +--- a/kernel/sysctl.c ++++ b/kernel/sysctl.c +@@ -105,6 +105,9 @@ extern int core_uses_pid; + extern char core_pattern[]; + extern unsigned int core_pipe_limit; + #endif ++#ifdef CONFIG_USER_NS ++extern int unprivileged_userns_clone; ++#endif + extern int pid_max; + extern int pid_max_min, pid_max_max; + extern int percpu_pagelist_fraction; +@@ -519,6 +522,15 @@ static struct ctl_table kern_table[] = { + .proc_handler = proc_dointvec, + }, + #endif ++#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 246d4d4ce5c7..f64432b45cec 100644 +--- a/kernel/user_namespace.c ++++ b/kernel/user_namespace.c +@@ -26,6 +26,9 @@ + #include <linux/bsearch.h> + #include <linux/sort.h> + ++/* sysctl */ ++int unprivileged_userns_clone; ++ + static struct kmem_cache *user_ns_cachep __read_mostly; + static DEFINE_MUTEX(userns_state_mutex); + +-- +2.18.0 + |