1 files changed, 16 insertions, 89 deletions

diff --git a/fs/ecryptfs/messaging.c b/fs/ecryptfs/messaging.c
index c11911decdc1..b29bb8bfa8d9 100644
--- a/fs/ecryptfs/messaging.c
+++ b/fs/ecryptfs/messaging.c
@@ -32,8 +32,8 @@ static struct mutex ecryptfs_msg_ctx_lists_mux;
 static struct hlist_head *ecryptfs_daemon_hash;
 struct mutex ecryptfs_daemon_hash_mux;
 static int ecryptfs_hash_bits;
-#define ecryptfs_uid_hash(uid) \
-        hash_long((unsigned long)uid, ecryptfs_hash_bits)
+#define ecryptfs_current_euid_hash(uid) \
+                hash_long((unsigned long)current_euid(), ecryptfs_hash_bits)
 
 static u32 ecryptfs_msg_counter;
 static struct ecryptfs_msg_ctx *ecryptfs_msg_ctx_arr;
@@ -105,26 +105,24 @@ void ecryptfs_msg_ctx_alloc_to_free(struct ecryptfs_msg_ctx *msg_ctx)
 
 /**
  * ecryptfs_find_daemon_by_euid
- * @euid: The effective user id which maps to the desired daemon id
- * @user_ns: The namespace in which @euid applies
  * @daemon: If return value is zero, points to the desired daemon pointer
  *
  * Must be called with ecryptfs_daemon_hash_mux held.
  *
- * Search the hash list for the given user id.
+ * Search the hash list for the current effective user id.
  *
  * Returns zero if the user id exists in the list; non-zero otherwise.
  */
-int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon, uid_t euid,
-                                 struct user_namespace *user_ns)
+int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon)
 {
         struct hlist_node *elem;
         int rc;
 
         hlist_for_each_entry(*daemon, elem,
-                             &ecryptfs_daemon_hash[ecryptfs_uid_hash(euid)],
-                             euid_chain) {
-                if ((*daemon)->euid == euid && (*daemon)->user_ns == user_ns) {
+                            &ecryptfs_daemon_hash[ecryptfs_current_euid_hash()],
+                            euid_chain) {
+                if ((*daemon)->file->f_cred->euid == current_euid() &&
+                    (*daemon)->file->f_cred->user_ns == current_user_ns()) {
                         rc = 0;
                         goto out;
                 }
@@ -137,9 +135,7 @@ out:
 /**
  * ecryptfs_spawn_daemon - Create and initialize a new daemon struct
  * @daemon: Pointer to set to newly allocated daemon struct
- * @euid: Effective user id for the daemon
- * @user_ns: The namespace in which @euid applies
- * @pid: Process id for the daemon
+ * @file: File used when opening /dev/ecryptfs
  *
  * Must be called ceremoniously while in possession of
  * ecryptfs_sacred_daemon_hash_mux
@@ -147,8 +143,7 @@ out:
  * Returns zero on success; non-zero otherwise
  */
 int
-ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, uid_t euid,
-                      struct user_namespace *user_ns, struct pid *pid)
+ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, struct file *file)
 {
         int rc = 0;
 
@@ -159,16 +154,13 @@ ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, uid_t euid,
                        "GFP_KERNEL memory\n", __func__, sizeof(**daemon));
                 goto out;
         }
-        (*daemon)->euid = euid;
-        (*daemon)->user_ns = get_user_ns(user_ns);
-        (*daemon)->pid = get_pid(pid);
-        (*daemon)->task = current;
+        (*daemon)->file = file;
         mutex_init(&(*daemon)->mux);
         INIT_LIST_HEAD(&(*daemon)->msg_ctx_out_queue);
         init_waitqueue_head(&(*daemon)->wait);
         (*daemon)->num_queued_msg_ctx = 0;
         hlist_add_head(&(*daemon)->euid_chain,
-                       &ecryptfs_daemon_hash[ecryptfs_uid_hash(euid)]);
+                       &ecryptfs_daemon_hash[ecryptfs_current_euid_hash()]);
 out:
         return rc;
 }
@@ -188,9 +180,6 @@ int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon)
         if ((daemon->flags & ECRYPTFS_DAEMON_IN_READ)
             || (daemon->flags & ECRYPTFS_DAEMON_IN_POLL)) {
                 rc = -EBUSY;
-                printk(KERN_WARNING "%s: Attempt to destroy daemon with pid "
-                       "[0x%p], but it is in the midst of a read or a poll\n",
-                       __func__, daemon->pid);
                 mutex_unlock(&daemon->mux);
                 goto out;
         }
@@ -203,12 +192,6 @@ int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon)
                 ecryptfs_msg_ctx_alloc_to_free(msg_ctx);
         }
         hlist_del(&daemon->euid_chain);
-        if (daemon->task)
-                wake_up_process(daemon->task);
-        if (daemon->pid)
-                put_pid(daemon->pid);
-        if (daemon->user_ns)
-                put_user_ns(daemon->user_ns);
         mutex_unlock(&daemon->mux);
         kzfree(daemon);
 out:
@@ -219,8 +202,6 @@ out:
  * ecryptfs_process_reponse
  * @msg: The ecryptfs message received; the caller should sanity check
  *       msg->data_len and free the memory
- * @pid: The process ID of the userspace application that sent the
- *       message
  * @seq: The sequence number of the message; must match the sequence
  *       number for the existing message context waiting for this
  *       response
@@ -239,16 +220,11 @@ out:
  *
  * Returns zero on success; non-zero otherwise
  */
-int ecryptfs_process_response(struct ecryptfs_message *msg, uid_t euid,
-                              struct user_namespace *user_ns, struct pid *pid,
-                              u32 seq)
+int ecryptfs_process_response(struct ecryptfs_daemon *daemon,
+                              struct ecryptfs_message *msg, u32 seq)
 {
-        struct ecryptfs_daemon *uninitialized_var(daemon);
         struct ecryptfs_msg_ctx *msg_ctx;
         size_t msg_size;
-        struct nsproxy *nsproxy;
-        struct user_namespace *tsk_user_ns;
-        uid_t ctx_euid;
         int rc;
 
         if (msg->index >= ecryptfs_message_buf_len) {
@@ -261,51 +237,6 @@ int ecryptfs_process_response(struct ecryptfs_message *msg, uid_t euid,
         }
         msg_ctx = &ecryptfs_msg_ctx_arr[msg->index];
         mutex_lock(&msg_ctx->mux);
-        mutex_lock(&ecryptfs_daemon_hash_mux);
-        rcu_read_lock();
-        nsproxy = task_nsproxy(msg_ctx->task);
-        if (nsproxy == NULL) {
-                rc = -EBADMSG;
-                printk(KERN_ERR "%s: Receiving process is a zombie. Dropping "
-                       "message.\n", __func__);
-                rcu_read_unlock();
-                mutex_unlock(&ecryptfs_daemon_hash_mux);
-                goto wake_up;
-        }
-        tsk_user_ns = __task_cred(msg_ctx->task)->user_ns;
-        ctx_euid = task_euid(msg_ctx->task);
-        rc = ecryptfs_find_daemon_by_euid(&daemon, ctx_euid, tsk_user_ns);
-        rcu_read_unlock();
-        mutex_unlock(&ecryptfs_daemon_hash_mux);
-        if (rc) {
-                rc = -EBADMSG;
-                printk(KERN_WARNING "%s: User [%d] received a "
-                       "message response from process [0x%p] but does "
-                       "not have a registered daemon\n", __func__,
-                       ctx_euid, pid);
-                goto wake_up;
-        }
-        if (ctx_euid != euid) {
-                rc = -EBADMSG;
-                printk(KERN_WARNING "%s: Received message from user "
-                       "[%d]; expected message from user [%d]\n", __func__,
-                       euid, ctx_euid);
-                goto unlock;
-        }
-        if (tsk_user_ns != user_ns) {
-                rc = -EBADMSG;
-                printk(KERN_WARNING "%s: Received message from user_ns "
-                       "[0x%p]; expected message from user_ns [0x%p]\n",
-                       __func__, user_ns, tsk_user_ns);
-                goto unlock;
-        }
-        if (daemon->pid != pid) {
-                rc = -EBADMSG;
-                printk(KERN_ERR "%s: User [%d] sent a message response "
-                       "from an unrecognized process [0x%p]\n",
-                       __func__, ctx_euid, pid);
-                goto unlock;
-        }
         if (msg_ctx->state != ECRYPTFS_MSG_CTX_STATE_PENDING) {
                 rc = -EINVAL;
                 printk(KERN_WARNING "%s: Desired context element is not "
@@ -328,9 +259,8 @@ int ecryptfs_process_response(struct ecryptfs_message *msg, uid_t euid,
         }
         memcpy(msg_ctx->msg, msg, msg_size);
         msg_ctx->state = ECRYPTFS_MSG_CTX_STATE_DONE;
-        rc = 0;
-wake_up:
         wake_up_process(msg_ctx->task);
+        rc = 0;
 unlock:
         mutex_unlock(&msg_ctx->mux);
 out:
@@ -352,14 +282,11 @@ ecryptfs_send_message_locked(char *data, int data_len, u8 msg_type,
                              struct ecryptfs_msg_ctx **msg_ctx)
 {
         struct ecryptfs_daemon *daemon;
-        uid_t euid = current_euid();
         int rc;
 
-        rc = ecryptfs_find_daemon_by_euid(&daemon, euid, current_user_ns());
+        rc = ecryptfs_find_daemon_by_euid(&daemon);
         if (rc || !daemon) {
                 rc = -ENOTCONN;
-                printk(KERN_ERR "%s: User [%d] does not have a daemon "
-                       "registered\n", __func__, euid);
                 goto out;
         }
         mutex_lock(&ecryptfs_msg_ctx_lists_mux);