From 60d65f1f07a7d81d3eb3b91fc13fca80f2fdbb12 Mon Sep 17 00:00:00 2001 From: Tyler Hicks Date: Mon, 11 Jun 2012 10:21:34 -0700 Subject: eCryptfs: Fix lockdep warning in miscdev operations Don't grab the daemon mutex while holding the message context mutex. Addresses this lockdep warning: ecryptfsd/2141 is trying to acquire lock: (&ecryptfs_msg_ctx_arr[i].mux){+.+.+.}, at: [] ecryptfs_miscdev_read+0x143/0x470 [ecryptfs] but task is already holding lock: (&(*daemon)->mux){+.+...}, at: [] ecryptfs_miscdev_read+0x21c/0x470 [ecryptfs] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&(*daemon)->mux){+.+...}: [] lock_acquire+0x9d/0x220 [] __mutex_lock_common+0x5a/0x4b0 [] mutex_lock_nested+0x44/0x50 [] ecryptfs_send_miscdev+0x97/0x120 [ecryptfs] [] ecryptfs_send_message+0x134/0x1e0 [ecryptfs] [] ecryptfs_generate_key_packet_set+0x2fe/0xa80 [ecryptfs] [] ecryptfs_write_metadata+0x108/0x250 [ecryptfs] [] ecryptfs_create+0x130/0x250 [ecryptfs] [] vfs_create+0xb4/0x120 [] do_last+0x8c5/0xa10 [] path_openat+0xd9/0x460 [] do_filp_open+0x42/0xa0 [] do_sys_open+0xf8/0x1d0 [] sys_open+0x21/0x30 [] system_call_fastpath+0x16/0x1b -> #0 (&ecryptfs_msg_ctx_arr[i].mux){+.+.+.}: [] __lock_acquire+0x1bf8/0x1c50 [] lock_acquire+0x9d/0x220 [] __mutex_lock_common+0x5a/0x4b0 [] mutex_lock_nested+0x44/0x50 [] ecryptfs_miscdev_read+0x143/0x470 [ecryptfs] [] vfs_read+0xb3/0x180 [] sys_read+0x4d/0x90 [] system_call_fastpath+0x16/0x1b Signed-off-by: Tyler Hicks --- fs/ecryptfs/miscdev.c | 25 +++++++++++++------------ 1 file changed, 13 insertions(+), 12 deletions(-) (limited to 'fs/ecryptfs/miscdev.c') diff --git a/fs/ecryptfs/miscdev.c b/fs/ecryptfs/miscdev.c index 3a06f4043df..3c632ec412e 100644 --- a/fs/ecryptfs/miscdev.c +++ b/fs/ecryptfs/miscdev.c @@ -191,31 +191,32 @@ int ecryptfs_send_miscdev(char *data, size_t data_size, struct ecryptfs_msg_ctx *msg_ctx, u8 msg_type, u16 msg_flags, struct ecryptfs_daemon *daemon) { - int rc = 0; + struct ecryptfs_message *msg; - mutex_lock(&msg_ctx->mux); - msg_ctx->msg = kmalloc((sizeof(*msg_ctx->msg) + data_size), - GFP_KERNEL); - if (!msg_ctx->msg) { - rc = -ENOMEM; + msg = kmalloc((sizeof(*msg) + data_size), GFP_KERNEL); + if (!msg) { printk(KERN_ERR "%s: Out of memory whilst attempting " "to kmalloc(%zd, GFP_KERNEL)\n", __func__, - (sizeof(*msg_ctx->msg) + data_size)); - goto out_unlock; + (sizeof(*msg) + data_size)); + return -ENOMEM; } + + mutex_lock(&msg_ctx->mux); + msg_ctx->msg = msg; msg_ctx->msg->index = msg_ctx->index; msg_ctx->msg->data_len = data_size; msg_ctx->type = msg_type; memcpy(msg_ctx->msg->data, data, data_size); msg_ctx->msg_size = (sizeof(*msg_ctx->msg) + data_size); - mutex_lock(&daemon->mux); list_add_tail(&msg_ctx->daemon_out_list, &daemon->msg_ctx_out_queue); + mutex_unlock(&msg_ctx->mux); + + mutex_lock(&daemon->mux); daemon->num_queued_msg_ctx++; wake_up_interruptible(&daemon->wait); mutex_unlock(&daemon->mux); -out_unlock: - mutex_unlock(&msg_ctx->mux); - return rc; + + return 0; } /* -- cgit v1.2.3-70-g09d2 From 8dc6780587c99286c0d3de747a2946a76989414a Mon Sep 17 00:00:00 2001 From: Tyler Hicks Date: Mon, 11 Jun 2012 09:24:11 -0700 Subject: eCryptfs: Gracefully refuse miscdev file ops on inherited/passed files File operations on /dev/ecryptfs would BUG() when the operations were performed by processes other than the process that originally opened the file. This could happen with open files inherited after fork() or file descriptors passed through IPC mechanisms. Rather than calling BUG(), an error code can be safely returned in most situations. In ecryptfs_miscdev_release(), eCryptfs still needs to handle the release even if the last file reference is being held by a process that didn't originally open the file. ecryptfs_find_daemon_by_euid() will not be successful, so a pointer to the daemon is stored in the file's private_data. The private_data pointer is initialized when the miscdev file is opened and only used when the file is released. https://launchpad.net/bugs/994247 Signed-off-by: Tyler Hicks Reported-by: Sasha Levin Tested-by: Sasha Levin --- fs/ecryptfs/miscdev.c | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-) (limited to 'fs/ecryptfs/miscdev.c') diff --git a/fs/ecryptfs/miscdev.c b/fs/ecryptfs/miscdev.c index 3c632ec412e..c0038f6566d 100644 --- a/fs/ecryptfs/miscdev.c +++ b/fs/ecryptfs/miscdev.c @@ -49,7 +49,10 @@ ecryptfs_miscdev_poll(struct file *file, poll_table *pt) mutex_lock(&ecryptfs_daemon_hash_mux); /* TODO: Just use file->private_data? */ rc = ecryptfs_find_daemon_by_euid(&daemon, euid, current_user_ns()); - BUG_ON(rc || !daemon); + 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) { @@ -122,6 +125,7 @@ ecryptfs_miscdev_open(struct inode *inode, struct file *file) goto out_unlock_daemon; } daemon->flags |= ECRYPTFS_DAEMON_MISCDEV_OPEN; + file->private_data = daemon; atomic_inc(&ecryptfs_num_miscdev_opens); out_unlock_daemon: mutex_unlock(&daemon->mux); @@ -152,9 +156,9 @@ ecryptfs_miscdev_release(struct inode *inode, struct file *file) mutex_lock(&ecryptfs_daemon_hash_mux); rc = ecryptfs_find_daemon_by_euid(&daemon, euid, current_user_ns()); - BUG_ON(rc || !daemon); + if (rc || !daemon) + daemon = file->private_data; mutex_lock(&daemon->mux); - BUG_ON(daemon->pid != task_pid(current)); BUG_ON(!(daemon->flags & ECRYPTFS_DAEMON_MISCDEV_OPEN)); daemon->flags &= ~ECRYPTFS_DAEMON_MISCDEV_OPEN; atomic_dec(&ecryptfs_num_miscdev_opens); @@ -270,8 +274,16 @@ ecryptfs_miscdev_read(struct file *file, char __user *buf, size_t count, mutex_lock(&ecryptfs_daemon_hash_mux); /* TODO: Just use file->private_data? */ rc = ecryptfs_find_daemon_by_euid(&daemon, euid, current_user_ns()); - BUG_ON(rc || !daemon); + 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); @@ -308,9 +320,6 @@ check_list: * message from the queue; try again */ goto check_list; } - BUG_ON(euid != daemon->euid); - BUG_ON(current_user_ns() != daemon->user_ns); - BUG_ON(task_pid(current) != daemon->pid); msg_ctx = list_first_entry(&daemon->msg_ctx_out_queue, struct ecryptfs_msg_ctx, daemon_out_list); BUG_ON(!msg_ctx); -- cgit v1.2.3-70-g09d2 From 2ecaf55db6dcf4dd25e1ef8d5eb6068e3286a20f Mon Sep 17 00:00:00 2001 From: Tyler Hicks Date: Mon, 11 Jun 2012 09:47:47 -0700 Subject: eCryptfs: Make all miscdev functions use daemon ptr in file private_data Now that a pointer to a valid struct ecryptfs_daemon is stored in the private_data of an opened /dev/ecryptfs file, the remaining miscdev functions can utilize the pointer rather than looking up the ecryptfs_daemon at the beginning of each operation. The security model of /dev/ecryptfs is simplified a little bit with this patch. Upon opening /dev/ecryptfs, a per-user ecryptfs_daemon is registered. Another daemon cannot be registered for that user until the last file reference is released. During the lifetime of the ecryptfs_daemon, access checks are not performed on the /dev/ecryptfs operations because it is assumed that the application securely handles the opened file descriptor and does not unintentionally leak it to processes that are not trusted. Signed-off-by: Tyler Hicks Cc: Sasha Levin --- fs/ecryptfs/ecryptfs_kernel.h | 16 ++----- fs/ecryptfs/messaging.c | 105 +++++++----------------------------------- fs/ecryptfs/miscdev.c | 98 +++++++++++---------------------------- 3 files changed, 47 insertions(+), 172 deletions(-) (limited to 'fs/ecryptfs/miscdev.c') diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h index 01a1f857595..0deb4f24957 100644 --- a/fs/ecryptfs/ecryptfs_kernel.h +++ b/fs/ecryptfs/ecryptfs_kernel.h @@ -392,10 +392,7 @@ struct ecryptfs_daemon { #define ECRYPTFS_DAEMON_MISCDEV_OPEN 0x00000008 u32 flags; u32 num_queued_msg_ctx; - struct pid *pid; - uid_t euid; - struct user_namespace *user_ns; - struct task_struct *task; + struct file *file; struct mutex mux; struct list_head msg_ctx_out_queue; wait_queue_head_t wait; @@ -619,9 +616,8 @@ int ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags); int ecryptfs_read_xattr_region(char *page_virt, struct inode *ecryptfs_inode); -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); int ecryptfs_send_message(char *data, int data_len, struct ecryptfs_msg_ctx **msg_ctx); int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx, @@ -666,8 +662,7 @@ int ecryptfs_read_lower_page_segment(struct page *page_for_ecryptfs, struct inode *ecryptfs_inode); struct page *ecryptfs_get_locked_page(struct inode *inode, loff_t index); int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon); -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); int ecryptfs_parse_packet_length(unsigned char *data, size_t *size, size_t *length_size); int ecryptfs_write_packet_length(char *dest, size_t size, @@ -679,8 +674,7 @@ int ecryptfs_send_miscdev(char *data, size_t data_size, u16 msg_flags, struct ecryptfs_daemon *daemon); void ecryptfs_msg_ctx_alloc_to_free(struct ecryptfs_msg_ctx *msg_ctx); 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 ecryptfs_init_kthread(void); void ecryptfs_destroy_kthread(void); int ecryptfs_privileged_open(struct file **lower_file, diff --git a/fs/ecryptfs/messaging.c b/fs/ecryptfs/messaging.c index c11911decdc..b29bb8bfa8d 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); diff --git a/fs/ecryptfs/miscdev.c b/fs/ecryptfs/miscdev.c index c0038f6566d..412e6eda25f 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", -- cgit v1.2.3-70-g09d2