From 9c37667302f104e0f412ba2727c4d3df81fb59da Mon Sep 17 00:00:00 2001 From: Paul Osmialowski Date: Tue, 26 May 2015 12:00:33 +0200 Subject: [RFC 5/8] kdbus: use LSM hooks in kdbus code Originates from: https://github.com/lmctl/kdbus.git (branch: kdbus-lsm-v4.for-systemd-v212) commit: aa0885489d19be92fa41c6f0a71df28763228a40 Signed-off-by: Karol Lewandowski Signed-off-by: Paul Osmialowski --- ipc/kdbus/bus.c | 11 ++++++++++- ipc/kdbus/bus.h | 5 +++++ ipc/kdbus/connection.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ ipc/kdbus/connection.h | 6 ++++++ ipc/kdbus/domain.c | 9 ++++++++- ipc/kdbus/domain.h | 4 ++++ ipc/kdbus/endpoint.c | 10 ++++++++++ ipc/kdbus/names.c | 10 ++++++++++ ipc/kdbus/queue.c | 30 ++++++++++++++++++++---------- 9 files changed, 121 insertions(+), 12 deletions(-) diff --git a/ipc/kdbus/bus.c b/ipc/kdbus/bus.c index bbdf0f2..be7ed81 100644 --- a/ipc/kdbus/bus.c +++ b/ipc/kdbus/bus.c @@ -22,6 +22,7 @@ #include #include #include +#include #include "bus.h" #include "notify.h" @@ -51,6 +52,7 @@ static void kdbus_bus_free(struct kdbus_node *node) kdbus_domain_unref(bus->domain); kdbus_policy_db_clear(&bus->policy_db); kdbus_meta_proc_unref(bus->creator_meta); + security_kdbus_bus_free(bus); kfree(bus); } @@ -161,6 +163,11 @@ static struct kdbus_bus *kdbus_bus_new(struct kdbus_domain *domain, goto exit_unref; } + ret = security_kdbus_bus_alloc(b); + if (ret) { + goto exit_unref; + } + /* * Bus-limits of the creator are accounted on its real UID, just like * all other per-user limits. @@ -169,11 +176,13 @@ static struct kdbus_bus *kdbus_bus_new(struct kdbus_domain *domain, if (IS_ERR(b->creator)) { ret = PTR_ERR(b->creator); b->creator = NULL; - goto exit_unref; + goto exit_free_security; } return b; +exit_free_security: + security_kdbus_bus_free(b); exit_unref: kdbus_node_deactivate(&b->node); kdbus_node_unref(&b->node); diff --git a/ipc/kdbus/bus.h b/ipc/kdbus/bus.h index 5bea5ef..521e692 100644 --- a/ipc/kdbus/bus.h +++ b/ipc/kdbus/bus.h @@ -53,6 +53,7 @@ struct kdbus_user; * @notify_list: List of pending kernel-generated messages * @notify_lock: Notification list lock * @notify_flush_lock: Notification flushing lock + * @security: LSM security blob */ struct kdbus_bus { struct kdbus_node node; @@ -81,6 +82,10 @@ struct kdbus_bus { struct list_head notify_list; spinlock_t notify_lock; struct mutex notify_flush_lock; + +#ifdef CONFIG_SECURITY + void *security; +#endif }; struct kdbus_bus *kdbus_bus_ref(struct kdbus_bus *bus); diff --git a/ipc/kdbus/connection.c b/ipc/kdbus/connection.c index 9993753..4b9f0b6 100644 --- a/ipc/kdbus/connection.c +++ b/ipc/kdbus/connection.c @@ -31,6 +31,7 @@ #include #include #include +#include #include "bus.h" #include "connection.h" @@ -73,6 +74,8 @@ static struct kdbus_conn *kdbus_conn_new(struct kdbus_ep *ep, bool privileged, bool is_activator; bool is_monitor; struct kvec kvec; + u32 sid, len; + char *label; int ret; struct { @@ -222,6 +225,13 @@ static struct kdbus_conn *kdbus_conn_new(struct kdbus_ep *ep, bool privileged, } } + security_task_getsecid(current, &sid); + security_secid_to_secctx(sid, &label, &len); + ret = security_kdbus_connect(conn, label, len); + if (ret) { + goto exit_unref; + } + if (atomic_inc_return(&conn->user->connections) > KDBUS_USER_MAX_CONN) { /* decremented by destructor as conn->user is valid */ ret = -EMFILE; @@ -276,6 +286,7 @@ static void __kdbus_conn_free(struct kref *kref) kdbus_pool_free(conn->pool); kdbus_ep_unref(conn->ep); put_cred(conn->cred); + security_kdbus_conn_free(conn); kfree(conn->description); kfree(conn->quota); kfree(conn); @@ -1107,6 +1118,11 @@ static int kdbus_conn_reply(struct kdbus_conn *src, struct kdbus_kmsg *kmsg) if (ret < 0) goto exit; + ret = security_kdbus_talk(src, dst); + if (ret) { + goto exit; + } + mutex_lock(&dst->lock); reply = kdbus_reply_find(src, dst, kmsg->msg.cookie_reply); if (reply) { @@ -1187,6 +1203,11 @@ static struct kdbus_reply *kdbus_conn_call(struct kdbus_conn *src, if (ret < 0) goto exit; + ret = security_kdbus_talk(src, dst); + if (ret) { + goto exit; + } + if (!kdbus_conn_policy_talk(src, current_cred(), dst)) { ret = -EPERM; goto exit; @@ -1248,6 +1269,11 @@ static int kdbus_conn_unicast(struct kdbus_conn *src, struct kdbus_kmsg *kmsg) if (ret < 0) goto exit; + ret = security_kdbus_talk(src, dst); + if (ret) { + goto exit; + } + if (is_signal) { /* like broadcasts we eavesdrop even if the msg is dropped */ kdbus_bus_eavesdrop(bus, src, kmsg); @@ -1639,6 +1665,11 @@ struct kdbus_conn *kdbus_cmd_hello(struct kdbus_ep *ep, bool privileged, if (ret < 0) goto exit; + ret = security_kdbus_ep_setpolicy(c->ep->bus); + if (ret) { + goto exit; + } + ret = kdbus_policy_set(&c->ep->bus->policy_db, args.items, args.items_size, 1, kdbus_conn_is_policy_holder(c), c); @@ -1732,6 +1763,10 @@ int kdbus_cmd_conn_info(struct kdbus_conn *conn, void __user *argp) if (ret != 0) return ret; + ret = security_kdbus_conn_info(conn); + if (ret) + return ret; + /* registry must be held throughout lookup *and* collecting data */ down_read(&bus->name_registry->rwlock); @@ -1905,6 +1940,11 @@ int kdbus_cmd_update(struct kdbus_conn *conn, void __user *argp) /* now that we verified the input, update the connection */ if (item_policy) { + ret = security_kdbus_ep_setpolicy(conn->ep->bus); + if (ret) { + goto exit; + } + ret = kdbus_policy_set(&conn->ep->bus->policy_db, cmd->items, KDBUS_ITEMS_SIZE(cmd, items), 1, true, conn); @@ -1948,6 +1988,10 @@ int kdbus_cmd_send(struct kdbus_conn *conn, struct file *f, void __user *argp) .argc = ARRAY_SIZE(argv), }; + ret = security_kdbus_send(conn, conn->ep->bus); + if (ret) + return ret; + if (!kdbus_conn_is_ordinary(conn)) return -EOPNOTSUPP; @@ -2044,6 +2088,10 @@ int kdbus_cmd_recv(struct kdbus_conn *conn, void __user *argp) .argc = ARRAY_SIZE(argv), }; + ret = security_kdbus_recv(conn, conn->ep->bus); + if (ret) + return ret; + if (!kdbus_conn_is_ordinary(conn) && !kdbus_conn_is_monitor(conn) && !kdbus_conn_is_activator(conn)) diff --git a/ipc/kdbus/connection.h b/ipc/kdbus/connection.h index d1ffe90..951f9b0 100644 --- a/ipc/kdbus/connection.h +++ b/ipc/kdbus/connection.h @@ -19,6 +19,7 @@ #include #include #include +#include #include "limits.h" #include "metadata.h" @@ -73,6 +74,7 @@ struct kdbus_kmsg; * @names_queue_list: Well-known names this connection waits for * @privileged: Whether this connection is privileged on the bus * @faked_meta: Whether the metadata was faked on HELLO + * @security: LSM security blob */ struct kdbus_conn { struct kref kref; @@ -113,6 +115,10 @@ struct kdbus_conn { bool privileged:1; bool faked_meta:1; + +#ifdef CONFIG_SECURITY + void *security; +#endif }; struct kdbus_conn *kdbus_conn_ref(struct kdbus_conn *conn); diff --git a/ipc/kdbus/domain.c b/ipc/kdbus/domain.c index ac9f760..e79080f 100644 --- a/ipc/kdbus/domain.c +++ b/ipc/kdbus/domain.c @@ -20,6 +20,7 @@ #include #include #include +#include #include "bus.h" #include "domain.h" @@ -73,6 +74,7 @@ static void kdbus_domain_free(struct kdbus_node *node) put_user_ns(domain->user_namespace); ida_destroy(&domain->user_ida); idr_destroy(&domain->user_idr); + security_kdbus_domain_free(domain); kfree(domain); } @@ -104,6 +106,10 @@ struct kdbus_domain *kdbus_domain_new(unsigned int access) idr_init(&d->user_idr); ida_init(&d->user_ida); + ret = security_kdbus_domain_alloc(d); + if (ret) + return ERR_PTR(ret); + /* Pin user namespace so we can guarantee domain-unique bus * names. */ d->user_namespace = get_user_ns(current_user_ns()); @@ -116,6 +122,7 @@ struct kdbus_domain *kdbus_domain_new(unsigned int access) exit_unref: kdbus_node_deactivate(&d->node); kdbus_node_unref(&d->node); + security_kdbus_domain_free(d); return ERR_PTR(ret); } @@ -264,7 +271,7 @@ static void __kdbus_user_free(struct kref *kref) if (uid_valid(user->uid)) idr_remove(&user->domain->user_idr, __kuid_val(user->uid)); mutex_unlock(&user->domain->lock); - + security_kdbus_domain_free(user->domain); kdbus_domain_unref(user->domain); kfree(user); } diff --git a/ipc/kdbus/domain.h b/ipc/kdbus/domain.h index 447a2bd..4a935aa 100644 --- a/ipc/kdbus/domain.h +++ b/ipc/kdbus/domain.h @@ -31,6 +31,7 @@ * @user_ida: Set of all users to compute small indices * @user_namespace: User namespace, pinned at creation time * @dentry: Root dentry of VFS mount (don't use outside of kdbusfs) + * @security: LSM security blob */ struct kdbus_domain { struct kdbus_node node; @@ -40,6 +41,9 @@ struct kdbus_domain { struct ida user_ida; struct user_namespace *user_namespace; struct dentry *dentry; +#ifdef CONFIG_SECURITY + void *security; +#endif }; /** diff --git a/ipc/kdbus/endpoint.c b/ipc/kdbus/endpoint.c index 9a95a5e..6ff74ee 100644 --- a/ipc/kdbus/endpoint.c +++ b/ipc/kdbus/endpoint.c @@ -21,6 +21,7 @@ #include #include #include +#include #include "bus.h" #include "connection.h" @@ -122,6 +123,11 @@ struct kdbus_ep *kdbus_ep_new(struct kdbus_bus *bus, const char *name, kdbus_policy_db_init(&e->policy_db); e->bus = kdbus_bus_ref(bus); + ret = security_kdbus_ep_create(bus); + if (ret) { + goto exit_unref; + } + ret = kdbus_node_link(&e->node, &bus->node, name); if (ret < 0) goto exit_unref; @@ -265,6 +271,10 @@ int kdbus_cmd_ep_update(struct kdbus_ep *ep, void __user *argp) .argc = ARRAY_SIZE(argv), }; + ret = security_kdbus_ep_setpolicy(ep->bus); + if (ret) + return ret; + ret = kdbus_args_parse(&args, argp, &cmd); if (ret != 0) return ret; diff --git a/ipc/kdbus/names.c b/ipc/kdbus/names.c index d77ee08..fcc1a49 100644 --- a/ipc/kdbus/names.c +++ b/ipc/kdbus/names.c @@ -24,6 +24,7 @@ #include #include #include +#include #include "bus.h" #include "connection.h" @@ -503,6 +504,11 @@ int kdbus_cmd_name_acquire(struct kdbus_conn *conn, void __user *argp) goto exit; } + ret = security_kdbus_name_acquire(conn, item_name); + if (ret) { + goto exit; + } + /* * Do atomic_inc_return here to reserve our slot, then decrement * it before returning. @@ -724,6 +730,10 @@ int kdbus_cmd_list(struct kdbus_conn *conn, void __user *argp) if (ret != 0) return ret; + ret = security_kdbus_name_list(conn->ep->bus); + if (ret) + return ret; + /* lock order: domain -> bus -> ep -> names -> conn */ down_read(®->rwlock); down_read(&conn->ep->bus->conn_rwlock); diff --git a/ipc/kdbus/queue.c b/ipc/kdbus/queue.c index 25bb3ad..9872fb4 100644 --- a/ipc/kdbus/queue.c +++ b/ipc/kdbus/queue.c @@ -28,6 +28,7 @@ #include #include #include +#include #include "util.h" #include "domain.h" @@ -514,12 +515,17 @@ int kdbus_queue_entry_install(struct kdbus_queue_entry *entry, for (i = 0; i < res->fds_count; i++) { if (install_fds) { - fds[i] = get_unused_fd_flags(O_CLOEXEC); - if (fds[i] >= 0) - fd_install(fds[i], - get_file(res->fds[i])); - else + if (security_file_receive(res->fds[i])) { + fds[i] = -1; incomplete_fds = true; + } else { + fds[i] = get_unused_fd_flags(O_CLOEXEC); + if (fds[i] >= 0) + fd_install(fds[i], + get_file(res->fds[i])); + else + incomplete_fds = true; + } } else { fds[i] = -1; } @@ -557,13 +563,17 @@ int kdbus_queue_entry_install(struct kdbus_queue_entry *entry, m.fd = -1; if (install_fds) { - m.fd = get_unused_fd_flags(O_CLOEXEC); - if (m.fd < 0) { - m.fd = -1; + if (security_file_receive(d->memfd.file)) { incomplete_fds = true; } else { - fd_install(m.fd, - get_file(d->memfd.file)); + m.fd = get_unused_fd_flags(O_CLOEXEC); + if (m.fd < 0) { + m.fd = -1; + incomplete_fds = true; + } else { + fd_install(m.fd, + get_file(d->memfd.file)); + } } } -- 1.9.1