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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /fs/ecryptfs/miscdev.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'fs/ecryptfs/miscdev.c')
-rw-r--r--fs/ecryptfs/miscdev.c499
1 files changed, 499 insertions, 0 deletions
diff --git a/fs/ecryptfs/miscdev.c b/fs/ecryptfs/miscdev.c
new file mode 100644
index 000000000..68804399a
--- /dev/null
+++ b/fs/ecryptfs/miscdev.c
@@ -0,0 +1,499 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 2008 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com>
+ */
+
+#include <linux/fs.h>
+#include <linux/hash.h>
+#include <linux/random.h>
+#include <linux/miscdevice.h>
+#include <linux/overflow.h>
+#include <linux/poll.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+#include <linux/module.h>
+#include "ecryptfs_kernel.h"
+
+static atomic_t ecryptfs_num_miscdev_opens;
+
+/**
+ * ecryptfs_miscdev_poll
+ * @file: dev file
+ * @pt: dev poll table (ignored)
+ *
+ * Returns the poll mask
+ */
+static __poll_t
+ecryptfs_miscdev_poll(struct file *file, poll_table *pt)
+{
+ struct ecryptfs_daemon *daemon = file->private_data;
+ __poll_t mask = 0;
+
+ mutex_lock(&daemon->mux);
+ if (daemon->flags & ECRYPTFS_DAEMON_ZOMBIE) {
+ printk(KERN_WARNING "%s: Attempt to poll on zombified "
+ "daemon\n", __func__);
+ goto out_unlock_daemon;
+ }
+ if (daemon->flags & ECRYPTFS_DAEMON_IN_READ)
+ goto out_unlock_daemon;
+ if (daemon->flags & ECRYPTFS_DAEMON_IN_POLL)
+ goto out_unlock_daemon;
+ daemon->flags |= ECRYPTFS_DAEMON_IN_POLL;
+ mutex_unlock(&daemon->mux);
+ poll_wait(file, &daemon->wait, pt);
+ mutex_lock(&daemon->mux);
+ if (!list_empty(&daemon->msg_ctx_out_queue))
+ mask |= EPOLLIN | EPOLLRDNORM;
+out_unlock_daemon:
+ daemon->flags &= ~ECRYPTFS_DAEMON_IN_POLL;
+ mutex_unlock(&daemon->mux);
+ return mask;
+}
+
+/**
+ * ecryptfs_miscdev_open
+ * @inode: inode of miscdev handle (ignored)
+ * @file: file for miscdev handle
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int
+ecryptfs_miscdev_open(struct inode *inode, struct file *file)
+{
+ struct ecryptfs_daemon *daemon = NULL;
+ int rc;
+
+ mutex_lock(&ecryptfs_daemon_hash_mux);
+ rc = ecryptfs_find_daemon_by_euid(&daemon);
+ if (!rc) {
+ rc = -EINVAL;
+ 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_unlock_daemon_list;
+ }
+ mutex_lock(&daemon->mux);
+ if (daemon->flags & ECRYPTFS_DAEMON_MISCDEV_OPEN) {
+ rc = -EBUSY;
+ 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);
+out_unlock_daemon_list:
+ mutex_unlock(&ecryptfs_daemon_hash_mux);
+ return rc;
+}
+
+/**
+ * ecryptfs_miscdev_release
+ * @inode: inode of 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.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int
+ecryptfs_miscdev_release(struct inode *inode, struct file *file)
+{
+ struct ecryptfs_daemon *daemon = file->private_data;
+ int rc;
+
+ 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 "
+ "bug.\n", __func__, rc);
+ BUG();
+ }
+ return rc;
+}
+
+/**
+ * ecryptfs_send_miscdev
+ * @data: Data to send to daemon; may be NULL
+ * @data_size: Amount of data to send to daemon
+ * @msg_ctx: Message context, which is used to handle the reply. If
+ * this is NULL, then we do not expect a reply.
+ * @msg_type: Type of message
+ * @msg_flags: Flags for message
+ * @daemon: eCryptfs daemon object
+ *
+ * Add msg_ctx to queue and then, if it exists, notify the blocked
+ * miscdevess about the data being available. Must be called with
+ * ecryptfs_daemon_hash_mux held.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+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)
+{
+ struct ecryptfs_message *msg;
+ size_t msg_size;
+
+ msg_size = struct_size(msg, data, data_size);
+ msg = kmalloc(msg_size, GFP_KERNEL);
+ if (!msg)
+ 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 = msg_size;
+ 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);
+
+ return 0;
+}
+
+/*
+ * miscdevfs packet format:
+ * Octet 0: Type
+ * Octets 1-4: network byte order msg_ctx->counter
+ * Octets 5-N0: Size of struct ecryptfs_message to follow
+ * Octets N0-N1: struct ecryptfs_message (including data)
+ *
+ * Octets 5-N1 not written if the packet type does not include a message
+ */
+#define PKT_TYPE_SIZE 1
+#define PKT_CTR_SIZE 4
+#define MIN_NON_MSG_PKT_SIZE (PKT_TYPE_SIZE + PKT_CTR_SIZE)
+#define MIN_MSG_PKT_SIZE (PKT_TYPE_SIZE + PKT_CTR_SIZE \
+ + ECRYPTFS_MIN_PKT_LEN_SIZE)
+/* 4 + ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES comes from tag 65 packet format */
+#define MAX_MSG_PKT_SIZE (PKT_TYPE_SIZE + PKT_CTR_SIZE \
+ + ECRYPTFS_MAX_PKT_LEN_SIZE \
+ + sizeof(struct ecryptfs_message) \
+ + 4 + ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES)
+#define PKT_TYPE_OFFSET 0
+#define PKT_CTR_OFFSET PKT_TYPE_SIZE
+#define PKT_LEN_OFFSET (PKT_TYPE_SIZE + PKT_CTR_SIZE)
+
+/**
+ * ecryptfs_miscdev_read - format and send message from queue
+ * @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)
+ *
+ * Pulls the most recent message from the daemon queue, formats it for
+ * being sent via a miscdevfs handle, and copies it into @buf
+ *
+ * Returns the number of bytes copied into the user buffer
+ */
+static ssize_t
+ecryptfs_miscdev_read(struct file *file, char __user *buf, size_t count,
+ loff_t *ppos)
+{
+ 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;
+ int rc;
+
+ mutex_lock(&daemon->mux);
+ if (daemon->flags & ECRYPTFS_DAEMON_ZOMBIE) {
+ rc = 0;
+ 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;
+ goto out_unlock_daemon;
+ }
+ /* This daemon will not go away so long as this flag is set */
+ daemon->flags |= ECRYPTFS_DAEMON_IN_READ;
+check_list:
+ if (list_empty(&daemon->msg_ctx_out_queue)) {
+ mutex_unlock(&daemon->mux);
+ rc = wait_event_interruptible(
+ daemon->wait, !list_empty(&daemon->msg_ctx_out_queue));
+ mutex_lock(&daemon->mux);
+ if (rc < 0) {
+ rc = 0;
+ goto out_unlock_daemon;
+ }
+ }
+ if (daemon->flags & ECRYPTFS_DAEMON_ZOMBIE) {
+ rc = 0;
+ goto out_unlock_daemon;
+ }
+ if (list_empty(&daemon->msg_ctx_out_queue)) {
+ /* Something else jumped in since the
+ * wait_event_interruptable() and removed the
+ * message from the queue; try again */
+ goto check_list;
+ }
+ msg_ctx = list_first_entry(&daemon->msg_ctx_out_queue,
+ struct ecryptfs_msg_ctx, daemon_out_list);
+ BUG_ON(!msg_ctx);
+ mutex_lock(&msg_ctx->mux);
+ if (msg_ctx->msg) {
+ rc = ecryptfs_write_packet_length(packet_length,
+ msg_ctx->msg_size,
+ &packet_length_size);
+ if (rc) {
+ rc = 0;
+ printk(KERN_WARNING "%s: Error writing packet length; "
+ "rc = [%d]\n", __func__, rc);
+ goto out_unlock_msg_ctx;
+ }
+ } else {
+ packet_length_size = 0;
+ msg_ctx->msg_size = 0;
+ }
+ total_length = (PKT_TYPE_SIZE + PKT_CTR_SIZE + packet_length_size
+ + msg_ctx->msg_size);
+ if (count < total_length) {
+ rc = 0;
+ printk(KERN_WARNING "%s: Only given user buffer of "
+ "size [%zd], but we need [%zd] to read the "
+ "pending message\n", __func__, count, total_length);
+ goto out_unlock_msg_ctx;
+ }
+ rc = -EFAULT;
+ if (put_user(msg_ctx->type, buf))
+ goto out_unlock_msg_ctx;
+ if (put_user(cpu_to_be32(msg_ctx->counter),
+ (__be32 __user *)(&buf[PKT_CTR_OFFSET])))
+ goto out_unlock_msg_ctx;
+ i = PKT_TYPE_SIZE + PKT_CTR_SIZE;
+ if (msg_ctx->msg) {
+ if (copy_to_user(&buf[i], packet_length, packet_length_size))
+ goto out_unlock_msg_ctx;
+ i += packet_length_size;
+ if (copy_to_user(&buf[i], msg_ctx->msg, msg_ctx->msg_size))
+ goto out_unlock_msg_ctx;
+ i += msg_ctx->msg_size;
+ }
+ rc = i;
+ list_del(&msg_ctx->daemon_out_list);
+ kfree(msg_ctx->msg);
+ msg_ctx->msg = NULL;
+ /* We do not expect a reply from the userspace daemon for any
+ * message type other than ECRYPTFS_MSG_REQUEST */
+ if (msg_ctx->type != ECRYPTFS_MSG_REQUEST)
+ ecryptfs_msg_ctx_alloc_to_free(msg_ctx);
+out_unlock_msg_ctx:
+ mutex_unlock(&msg_ctx->mux);
+out_unlock_daemon:
+ daemon->flags &= ~ECRYPTFS_DAEMON_IN_READ;
+ mutex_unlock(&daemon->mux);
+ return rc;
+}
+
+/**
+ * ecryptfs_miscdev_response - miscdevess response to message previously sent to daemon
+ * @daemon: eCryptfs daemon object
+ * @data: Bytes comprising struct ecryptfs_message
+ * @data_size: sizeof(struct ecryptfs_message) + data len
+ * @seq: Sequence number for miscdev response packet
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+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;
+
+ if ((sizeof(*msg) + msg->data_len) != data_size) {
+ printk(KERN_WARNING "%s: (sizeof(*msg) + msg->data_len) = "
+ "[%zd]; data_size = [%zd]. Invalid packet.\n", __func__,
+ (sizeof(*msg) + msg->data_len), data_size);
+ rc = -EINVAL;
+ goto out;
+ }
+ rc = ecryptfs_process_response(daemon, msg, seq);
+ if (rc)
+ printk(KERN_ERR
+ "Error processing response message; rc = [%d]\n", rc);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_miscdev_write - handle write to daemon miscdev handle
+ * @file: File for misc dev handle
+ * @buf: Buffer containing user data
+ * @count: Amount of data in @buf
+ * @ppos: Pointer to offset in file (ignored)
+ *
+ * Returns the number of bytes read from @buf
+ */
+static ssize_t
+ecryptfs_miscdev_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ __be32 counter_nbo;
+ u32 seq;
+ size_t packet_size, packet_size_length;
+ char *data;
+ unsigned char packet_size_peek[ECRYPTFS_MAX_PKT_LEN_SIZE] = { };
+ ssize_t rc;
+
+ if (count == 0) {
+ return 0;
+ } else if (count == MIN_NON_MSG_PKT_SIZE) {
+ /* Likely a harmless MSG_HELO or MSG_QUIT - no packet length */
+ goto memdup;
+ } else if (count < MIN_MSG_PKT_SIZE || count > MAX_MSG_PKT_SIZE) {
+ printk(KERN_WARNING "%s: Acceptable packet size range is "
+ "[%d-%zu], but amount of data written is [%zu].\n",
+ __func__, MIN_MSG_PKT_SIZE, MAX_MSG_PKT_SIZE, count);
+ return -EINVAL;
+ }
+
+ if (copy_from_user(packet_size_peek, &buf[PKT_LEN_OFFSET],
+ min_t(size_t, count - PKT_LEN_OFFSET,
+ sizeof(packet_size_peek)))) {
+ printk(KERN_WARNING "%s: Error while inspecting packet size\n",
+ __func__);
+ return -EFAULT;
+ }
+
+ rc = ecryptfs_parse_packet_length(packet_size_peek, &packet_size,
+ &packet_size_length);
+ if (rc) {
+ printk(KERN_WARNING "%s: Error parsing packet length; "
+ "rc = [%zd]\n", __func__, rc);
+ return rc;
+ }
+
+ if ((PKT_TYPE_SIZE + PKT_CTR_SIZE + packet_size_length + packet_size)
+ != count) {
+ printk(KERN_WARNING "%s: Invalid packet size [%zu]\n", __func__,
+ packet_size);
+ return -EINVAL;
+ }
+
+memdup:
+ data = memdup_user(buf, count);
+ if (IS_ERR(data)) {
+ printk(KERN_ERR "%s: memdup_user returned error [%ld]\n",
+ __func__, PTR_ERR(data));
+ return PTR_ERR(data);
+ }
+ switch (data[PKT_TYPE_OFFSET]) {
+ case ECRYPTFS_MSG_RESPONSE:
+ if (count < (MIN_MSG_PKT_SIZE
+ + sizeof(struct ecryptfs_message))) {
+ printk(KERN_WARNING "%s: Minimum acceptable packet "
+ "size is [%zd], but amount of data written is "
+ "only [%zd]. Discarding response packet.\n",
+ __func__,
+ (MIN_MSG_PKT_SIZE
+ + sizeof(struct ecryptfs_message)), count);
+ rc = -EINVAL;
+ goto out_free;
+ }
+ memcpy(&counter_nbo, &data[PKT_CTR_OFFSET], PKT_CTR_SIZE);
+ seq = be32_to_cpu(counter_nbo);
+ rc = ecryptfs_miscdev_response(file->private_data,
+ &data[PKT_LEN_OFFSET + packet_size_length],
+ packet_size, seq);
+ if (rc) {
+ printk(KERN_WARNING "%s: Failed to deliver miscdev "
+ "response to requesting operation; rc = [%zd]\n",
+ __func__, rc);
+ goto out_free;
+ }
+ break;
+ case ECRYPTFS_MSG_HELO:
+ case ECRYPTFS_MSG_QUIT:
+ break;
+ default:
+ ecryptfs_printk(KERN_WARNING, "Dropping miscdev "
+ "message of unrecognized type [%d]\n",
+ data[0]);
+ rc = -EINVAL;
+ goto out_free;
+ }
+ rc = count;
+out_free:
+ kfree(data);
+ return rc;
+}
+
+
+static const struct file_operations ecryptfs_miscdev_fops = {
+ .owner = THIS_MODULE,
+ .open = ecryptfs_miscdev_open,
+ .poll = ecryptfs_miscdev_poll,
+ .read = ecryptfs_miscdev_read,
+ .write = ecryptfs_miscdev_write,
+ .release = ecryptfs_miscdev_release,
+ .llseek = noop_llseek,
+};
+
+static struct miscdevice ecryptfs_miscdev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "ecryptfs",
+ .fops = &ecryptfs_miscdev_fops
+};
+
+/**
+ * ecryptfs_init_ecryptfs_miscdev
+ *
+ * Messages sent to the userspace daemon from the kernel are placed on
+ * a queue associated with the daemon. The next read against the
+ * miscdev handle by that daemon will return the oldest message placed
+ * on the message queue for the daemon.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+int __init ecryptfs_init_ecryptfs_miscdev(void)
+{
+ int rc;
+
+ atomic_set(&ecryptfs_num_miscdev_opens, 0);
+ rc = misc_register(&ecryptfs_miscdev);
+ if (rc)
+ printk(KERN_ERR "%s: Failed to register miscellaneous device "
+ "for communications with userspace daemons; rc = [%d]\n",
+ __func__, rc);
+ return rc;
+}
+
+/**
+ * ecryptfs_destroy_ecryptfs_miscdev
+ *
+ * All of the daemons must be exorcised prior to calling this
+ * function.
+ */
+void ecryptfs_destroy_ecryptfs_miscdev(void)
+{
+ BUG_ON(atomic_read(&ecryptfs_num_miscdev_opens) != 0);
+ misc_deregister(&ecryptfs_miscdev);
+}