1 files changed, 26 insertions, 72 deletions

diff --git a/fs/ecryptfs/miscdev.c b/fs/ecryptfs/miscdev.c
index c0038f6566d4..412e6eda25f8 100644
--- a/fs/ecryptfs/miscdev.c
+++ b/fs/ecryptfs/miscdev.c
@@ -33,7 +33,7 @@ static atomic_t ecryptfs_num_miscdev_opens;
 
 /**
  * ecryptfs_miscdev_poll
- * @file: dev file (ignored)
+ * @file: dev file
  * @pt: dev poll table (ignored)
  *
  * Returns the poll mask
@@ -41,20 +41,10 @@ static atomic_t ecryptfs_num_miscdev_opens;
 static unsigned int
 ecryptfs_miscdev_poll(struct file *file, poll_table *pt)
 {
-        struct ecryptfs_daemon *daemon;
+        struct ecryptfs_daemon *daemon = file->private_data;
         unsigned int mask = 0;
-        uid_t euid = current_euid();
-        int rc;
 
-        mutex_lock(&ecryptfs_daemon_hash_mux);
-        /* TODO: Just use file->private_data? */
-        rc = ecryptfs_find_daemon_by_euid(&daemon, euid, current_user_ns());
-        if (rc || !daemon) {
-                mutex_unlock(&ecryptfs_daemon_hash_mux);
-                return -EINVAL;
-        }
         mutex_lock(&daemon->mux);
-        mutex_unlock(&ecryptfs_daemon_hash_mux);
         if (daemon->flags & ECRYPTFS_DAEMON_ZOMBIE) {
                 printk(KERN_WARNING "%s: Attempt to poll on zombified "
                        "daemon\n", __func__);
@@ -79,7 +69,7 @@ out_unlock_daemon:
 /**
  * ecryptfs_miscdev_open
  * @inode: inode of miscdev handle (ignored)
- * @file: file for miscdev handle (ignored)
+ * @file: file for miscdev handle
  *
  * Returns zero on success; non-zero otherwise
  */
@@ -87,7 +77,6 @@ static int
 ecryptfs_miscdev_open(struct inode *inode, struct file *file)
 {
         struct ecryptfs_daemon *daemon = NULL;
-        uid_t euid = current_euid();
         int rc;
 
         mutex_lock(&ecryptfs_daemon_hash_mux);
@@ -98,30 +87,20 @@ ecryptfs_miscdev_open(struct inode *inode, struct file *file)
                        "count; rc = [%d]\n", __func__, rc);
                 goto out_unlock_daemon_list;
         }
-        rc = ecryptfs_find_daemon_by_euid(&daemon, euid, current_user_ns());
-        if (rc || !daemon) {
-                rc = ecryptfs_spawn_daemon(&daemon, euid, current_user_ns(),
-                                           task_pid(current));
-                if (rc) {
-                        printk(KERN_ERR "%s: Error attempting to spawn daemon; "
-                               "rc = [%d]\n", __func__, rc);
-                        goto out_module_put_unlock_daemon_list;
-                }
-        }
-        mutex_lock(&daemon->mux);
-        if (daemon->pid != task_pid(current)) {
+        rc = ecryptfs_find_daemon_by_euid(&daemon);
+        if (!rc) {
                 rc = -EINVAL;
-                printk(KERN_ERR "%s: pid [0x%p] has registered with euid [%d], "
-                       "but pid [0x%p] has attempted to open the handle "
-                       "instead\n", __func__, daemon->pid, daemon->euid,
-                       task_pid(current));
-                goto out_unlock_daemon;
+                goto out_unlock_daemon_list;
+        }
+        rc = ecryptfs_spawn_daemon(&daemon, file);
+        if (rc) {
+                printk(KERN_ERR "%s: Error attempting to spawn daemon; "
+                       "rc = [%d]\n", __func__, rc);
+                goto out_module_put_unlock_daemon_list;
         }
+        mutex_lock(&daemon->mux);
         if (daemon->flags & ECRYPTFS_DAEMON_MISCDEV_OPEN) {
                 rc = -EBUSY;
-                printk(KERN_ERR "%s: Miscellaneous device handle may only be "
-                       "opened once per daemon; pid [0x%p] already has this "
-                       "handle open\n", __func__, daemon->pid);
                 goto out_unlock_daemon;
         }
         daemon->flags |= ECRYPTFS_DAEMON_MISCDEV_OPEN;
@@ -140,7 +119,7 @@ out_unlock_daemon_list:
 /**
  * ecryptfs_miscdev_release
  * @inode: inode of fs/ecryptfs/euid handle (ignored)
- * @file: file for fs/ecryptfs/euid handle (ignored)
+ * @file: file for fs/ecryptfs/euid handle
  *
  * This keeps the daemon registered until the daemon sends another
  * ioctl to fs/ecryptfs/ctl or until the kernel module unregisters.
@@ -150,20 +129,18 @@ out_unlock_daemon_list:
 static int
 ecryptfs_miscdev_release(struct inode *inode, struct file *file)
 {
-        struct ecryptfs_daemon *daemon = NULL;
-        uid_t euid = current_euid();
+        struct ecryptfs_daemon *daemon = file->private_data;
         int rc;
 
-        mutex_lock(&ecryptfs_daemon_hash_mux);
-        rc = ecryptfs_find_daemon_by_euid(&daemon, euid, current_user_ns());
-        if (rc || !daemon)
-                daemon = file->private_data;
         mutex_lock(&daemon->mux);
         BUG_ON(!(daemon->flags & ECRYPTFS_DAEMON_MISCDEV_OPEN));
         daemon->flags &= ~ECRYPTFS_DAEMON_MISCDEV_OPEN;
         atomic_dec(&ecryptfs_num_miscdev_opens);
         mutex_unlock(&daemon->mux);
+
+        mutex_lock(&ecryptfs_daemon_hash_mux);
         rc = ecryptfs_exorcise_daemon(daemon);
+        mutex_unlock(&ecryptfs_daemon_hash_mux);
         if (rc) {
                 printk(KERN_CRIT "%s: Fatal error whilst attempting to "
                        "shut down daemon; rc = [%d]. Please report this "
@@ -171,7 +148,6 @@ ecryptfs_miscdev_release(struct inode *inode, struct file *file)
                 BUG();
         }
         module_put(THIS_MODULE);
-        mutex_unlock(&ecryptfs_daemon_hash_mux);
         return rc;
 }
 
@@ -248,7 +224,7 @@ int ecryptfs_send_miscdev(char *data, size_t data_size,
 
 /**
  * ecryptfs_miscdev_read - format and send message from queue
- * @file: fs/ecryptfs/euid miscdevfs handle (ignored)
+ * @file: miscdevfs handle
  * @buf: User buffer into which to copy the next message on the daemon queue
  * @count: Amount of space available in @buf
  * @ppos: Offset in file (ignored)
@@ -262,43 +238,27 @@ static ssize_t
 ecryptfs_miscdev_read(struct file *file, char __user *buf, size_t count,
                       loff_t *ppos)
 {
-        struct ecryptfs_daemon *daemon;
+        struct ecryptfs_daemon *daemon = file->private_data;
         struct ecryptfs_msg_ctx *msg_ctx;
         size_t packet_length_size;
         char packet_length[ECRYPTFS_MAX_PKT_LEN_SIZE];
         size_t i;
         size_t total_length;
-        uid_t euid = current_euid();
         int rc;
 
-        mutex_lock(&ecryptfs_daemon_hash_mux);
-        /* TODO: Just use file->private_data? */
-        rc = ecryptfs_find_daemon_by_euid(&daemon, euid, current_user_ns());
-        if (rc || !daemon) {
-                mutex_unlock(&ecryptfs_daemon_hash_mux);
-                return -EINVAL;
-        }
         mutex_lock(&daemon->mux);
-        if (task_pid(current) != daemon->pid) {
-                mutex_unlock(&daemon->mux);
-                mutex_unlock(&ecryptfs_daemon_hash_mux);
-                return -EPERM;
-        }
         if (daemon->flags & ECRYPTFS_DAEMON_ZOMBIE) {
                 rc = 0;
-                mutex_unlock(&ecryptfs_daemon_hash_mux);
                 printk(KERN_WARNING "%s: Attempt to read from zombified "
                        "daemon\n", __func__);
                 goto out_unlock_daemon;
         }
         if (daemon->flags & ECRYPTFS_DAEMON_IN_READ) {
                 rc = 0;
-                mutex_unlock(&ecryptfs_daemon_hash_mux);
                 goto out_unlock_daemon;
         }
         /* This daemon will not go away so long as this flag is set */
         daemon->flags |= ECRYPTFS_DAEMON_IN_READ;
-        mutex_unlock(&ecryptfs_daemon_hash_mux);
 check_list:
         if (list_empty(&daemon->msg_ctx_out_queue)) {
                 mutex_unlock(&daemon->mux);
@@ -382,16 +342,12 @@ out_unlock_daemon:
  * ecryptfs_miscdev_response - miscdevess response to message previously sent to daemon
  * @data: Bytes comprising struct ecryptfs_message
  * @data_size: sizeof(struct ecryptfs_message) + data len
- * @euid: Effective user id of miscdevess sending the miscdev response
- * @user_ns: The namespace in which @euid applies
- * @pid: Miscdevess id of miscdevess sending the miscdev response
  * @seq: Sequence number for miscdev response packet
  *
  * Returns zero on success; non-zero otherwise
  */
-static int ecryptfs_miscdev_response(char *data, size_t data_size,
-                                     uid_t euid, struct user_namespace *user_ns,
-                                     struct pid *pid, u32 seq)
+static int ecryptfs_miscdev_response(struct ecryptfs_daemon *daemon, char *data,
+                                     size_t data_size, u32 seq)
 {
         struct ecryptfs_message *msg = (struct ecryptfs_message *)data;
         int rc;
@@ -403,7 +359,7 @@ static int ecryptfs_miscdev_response(char *data, size_t data_size,
                 rc = -EINVAL;
                 goto out;
         }
-        rc = ecryptfs_process_response(msg, euid, user_ns, pid, seq);
+        rc = ecryptfs_process_response(daemon, msg, seq);
         if (rc)
                 printk(KERN_ERR
                        "Error processing response message; rc = [%d]\n", rc);
@@ -413,7 +369,7 @@ out:
 
 /**
  * ecryptfs_miscdev_write - handle write to daemon miscdev handle
- * @file: File for misc dev handle (ignored)
+ * @file: File for misc dev handle
  * @buf: Buffer containing user data
  * @count: Amount of data in @buf
  * @ppos: Pointer to offset in file (ignored)
@@ -428,7 +384,6 @@ ecryptfs_miscdev_write(struct file *file, const char __user *buf,
         u32 seq;
         size_t packet_size, packet_size_length;
         char *data;
-        uid_t euid = current_euid();
         unsigned char packet_size_peek[ECRYPTFS_MAX_PKT_LEN_SIZE];
         ssize_t rc;
 
@@ -488,10 +443,9 @@ memdup:
                 }
                 memcpy(&counter_nbo, &data[PKT_CTR_OFFSET], PKT_CTR_SIZE);
                 seq = be32_to_cpu(counter_nbo);
-                rc = ecryptfs_miscdev_response(
+                rc = ecryptfs_miscdev_response(file->private_data,
                                 &data[PKT_LEN_OFFSET + packet_size_length],
-                                packet_size, euid, current_user_ns(),
-                                task_pid(current), seq);
+                                packet_size, seq);
                 if (rc) {
                         printk(KERN_WARNING "%s: Failed to deliver miscdev "
                                "response to requesting operation; rc = [%zd]\n",