diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index 65c9609ec207..0da6c7e8f659 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -265,6 +265,9 @@ LSM_HOOK(int, -ENOSYS, task_prctl, int option, unsigned long arg2, LSM_HOOK(void, LSM_RET_VOID, task_to_inode, struct task_struct *p, struct inode *inode) LSM_HOOK(int, 0, userns_create, const struct cred *cred) +LSM_HOOK(int, 0, namespace_init, struct ns_common *ns) +LSM_HOOK(void, LSM_RET_VOID, namespace_free, struct ns_common *ns) +LSM_HOOK(int, 0, namespace_install, const struct nsset *nsset, struct ns_common *ns) LSM_HOOK(int, 0, ipc_permission, struct kern_ipc_perm *ipcp, short flag) LSM_HOOK(void, LSM_RET_VOID, ipc_getlsmprop, struct kern_ipc_perm *ipcp, struct lsm_prop *prop) diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index c4488c4a6d8a..13621e9e233e 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -112,6 +112,7 @@ struct lsm_blob_sizes { unsigned int lbs_ipc; unsigned int lbs_key; unsigned int lbs_msg_msg; + unsigned int lbs_ns; unsigned int lbs_perf_event; unsigned int lbs_task; unsigned int lbs_xattr_count; /* num xattr slots in new_xattrs array */ diff --git a/include/linux/ns/ns_common_types.h b/include/linux/ns/ns_common_types.h index ea45c54e4435..5cfe0ce3c881 100644 --- a/include/linux/ns/ns_common_types.h +++ b/include/linux/ns/ns_common_types.h @@ -116,6 +116,9 @@ struct ns_common { struct dentry *stashed; const struct proc_ns_operations *ops; unsigned int inum; +#ifdef CONFIG_SECURITY + void *ns_security; +#endif union { struct ns_tree; struct rcu_head ns_rcu; diff --git a/include/linux/security.h b/include/linux/security.h index 153e9043058f..bf002ed14ac8 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -67,6 +67,7 @@ enum fs_value_type; struct watch; struct watch_notification; struct lsm_ctx; +struct nsset; /* Default (no) options for the capable function */ #define CAP_OPT_NONE 0x0 @@ -80,6 +81,7 @@ struct lsm_ctx; struct ctl_table; struct audit_krule; +struct ns_common; struct user_namespace; struct timezone; @@ -540,6 +542,9 @@ int security_task_prctl(int option, unsigned long arg2, unsigned long arg3, unsigned long arg4, unsigned long arg5); void security_task_to_inode(struct task_struct *p, struct inode *inode); int security_create_user_ns(const struct cred *cred); +int security_namespace_init(struct ns_common *ns); +void security_namespace_free(struct ns_common *ns); +int security_namespace_install(const struct nsset *nsset, struct ns_common *ns); int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag); void security_ipc_getlsmprop(struct kern_ipc_perm *ipcp, struct lsm_prop *prop); int security_msg_msg_alloc(struct msg_msg *msg); @@ -1431,6 +1436,21 @@ static inline int security_create_user_ns(const struct cred *cred) return 0; } +static inline int security_namespace_init(struct ns_common *ns) +{ + return 0; +} + +static inline void security_namespace_free(struct ns_common *ns) +{ +} + +static inline int security_namespace_install(const struct nsset *nsset, + struct ns_common *ns) +{ + return 0; +} + static inline int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag) { diff --git a/kernel/nscommon.c b/kernel/nscommon.c index e6f623e1bc37..e72426bba29a 100644 --- a/kernel/nscommon.c +++ b/kernel/nscommon.c @@ -4,6 +4,7 @@ #include #include #include +#include #include #include @@ -59,6 +60,9 @@ int __ns_common_init(struct ns_common *ns, u32 ns_type, const struct proc_ns_ope refcount_set(&ns->__ns_ref, 1); ns->stashed = NULL; +#ifdef CONFIG_SECURITY + ns->ns_security = NULL; +#endif ns->ops = ops; ns->ns_id = 0; ns->ns_type = ns_type; @@ -77,6 +81,14 @@ int __ns_common_init(struct ns_common *ns, u32 ns_type, const struct proc_ns_ope ret = proc_alloc_inum(&ns->inum); if (ret) return ret; + + ret = security_namespace_init(ns); + if (ret) { + if (!inum) + proc_free_inum(ns->inum); + return ret; + } + /* * Tree ref starts at 0. It's incremented when namespace enters * active use (installed in nsproxy) and decremented when all @@ -91,6 +103,8 @@ int __ns_common_init(struct ns_common *ns, u32 ns_type, const struct proc_ns_ope void __ns_common_free(struct ns_common *ns) { + security_namespace_free(ns); + if (ns->inum > MNT_NS_INO_SPECIAL_MAX) proc_free_inum(ns->inum); } diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c index d9d3d5973bf5..0f1b208d8eef 100644 --- a/kernel/nsproxy.c +++ b/kernel/nsproxy.c @@ -385,6 +385,12 @@ static int prepare_nsset(unsigned flags, struct nsset *nsset) static inline int validate_ns(struct nsset *nsset, struct ns_common *ns) { + int ret; + + ret = security_namespace_install(nsset, ns); + if (ret) + return ret; + return ns->ops->install(nsset, ns); } diff --git a/security/lsm_init.c b/security/lsm_init.c index 04b18d06ba59..751da523bb42 100644 --- a/security/lsm_init.c +++ b/security/lsm_init.c @@ -303,6 +303,7 @@ static void __init lsm_prepare(struct lsm_info *lsm) lsm_blob_size_update(&blobs->lbs_ipc, &blob_sizes.lbs_ipc); lsm_blob_size_update(&blobs->lbs_key, &blob_sizes.lbs_key); lsm_blob_size_update(&blobs->lbs_msg_msg, &blob_sizes.lbs_msg_msg); + lsm_blob_size_update(&blobs->lbs_ns, &blob_sizes.lbs_ns); lsm_blob_size_update(&blobs->lbs_perf_event, &blob_sizes.lbs_perf_event); lsm_blob_size_update(&blobs->lbs_sock, &blob_sizes.lbs_sock); @@ -450,6 +451,7 @@ int __init security_init(void) lsm_pr("blob(ipc) size %d\n", blob_sizes.lbs_ipc); lsm_pr("blob(key) size %d\n", blob_sizes.lbs_key); lsm_pr("blob(msg_msg)_size %d\n", blob_sizes.lbs_msg_msg); + lsm_pr("blob(ns) size %d\n", blob_sizes.lbs_ns); lsm_pr("blob(sock) size %d\n", blob_sizes.lbs_sock); lsm_pr("blob(superblock) size %d\n", blob_sizes.lbs_superblock); lsm_pr("blob(perf_event) size %d\n", blob_sizes.lbs_perf_event); diff --git a/security/security.c b/security/security.c index 2ee276ab15c5..b284e24e3771 100644 --- a/security/security.c +++ b/security/security.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include #include @@ -381,6 +382,19 @@ static int lsm_superblock_alloc(struct super_block *sb) GFP_KERNEL); } +/** + * lsm_ns_alloc - allocate a composite namespace blob + * @ns: the namespace that needs a blob + * + * Allocate the namespace blob for all the modules + * + * Returns 0, or -ENOMEM if memory can't be allocated. + */ +static int lsm_ns_alloc(struct ns_common *ns) +{ + return lsm_blob_alloc(&ns->ns_security, blob_sizes.lbs_ns, GFP_KERNEL); +} + /** * lsm_fill_user_ctx - Fill a user space lsm_ctx structure * @uctx: a userspace LSM context to be filled @@ -3357,6 +3371,64 @@ int security_create_user_ns(const struct cred *cred) return call_int_hook(userns_create, cred); } +/** + * security_namespace_init() - Initialize LSM security data for a namespace + * @ns: the namespace being initialized + * + * Initialize the LSM security blob attached to the namespace. The namespace type + * is available via ns->ns_type, and the owning user namespace (if any) + * via ns->ops->owner(ns). + * + * Return: Returns 0 if successful, otherwise < 0 error code. + */ +int security_namespace_init(struct ns_common *ns) +{ + int rc; + + rc = lsm_ns_alloc(ns); + if (unlikely(rc)) + return rc; + + rc = call_int_hook(namespace_init, ns); + if (unlikely(rc)) + security_namespace_free(ns); + + return rc; +} + +/** + * security_namespace_free() - Release LSM security data from a namespace + * @ns: the namespace being freed + * + * Release security data attached to the namespace. Called before the + * namespace structure is freed. + */ +void security_namespace_free(struct ns_common *ns) +{ + if (!ns->ns_security) + return; + + call_void_hook(namespace_free, ns); + + kfree(ns->ns_security); + ns->ns_security = NULL; +} + +/** + * security_namespace_install() - Check permission to install a namespace + * @nsset: the target nsset being configured + * @ns: the namespace being installed + * + * Check permission before allowing a namespace to be installed into the + * process's set of namespaces via setns(2). + * + * Return: Returns 0 if permission is granted, otherwise < 0 error code. + */ +int security_namespace_install(const struct nsset *nsset, struct ns_common *ns) +{ + return call_int_hook(namespace_install, nsset, ns); +} + /** * security_ipc_permission() - Check if sysv ipc access is allowed * @ipcp: ipc permission structure