Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/char/tpm/tpm-dev-common.c b/drivers/char/tpm/tpm-dev-common.c
index e4a04b2..2ec47a6 100644
--- a/drivers/char/tpm/tpm-dev-common.c
+++ b/drivers/char/tpm/tpm-dev-common.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2004 IBM Corporation
* Authors:
@@ -10,18 +11,67 @@
* Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
*
* Device file system interface to the TPM
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation, version 2 of the
- * License.
- *
*/
+#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
+#include <linux/workqueue.h>
#include "tpm.h"
#include "tpm-dev.h"
+static struct workqueue_struct *tpm_dev_wq;
+static DEFINE_MUTEX(tpm_dev_wq_lock);
+
+static ssize_t tpm_dev_transmit(struct tpm_chip *chip, struct tpm_space *space,
+ u8 *buf, size_t bufsiz)
+{
+ struct tpm_header *header = (void *)buf;
+ ssize_t ret, len;
+
+ ret = tpm2_prepare_space(chip, space, buf, bufsiz);
+ /* If the command is not implemented by the TPM, synthesize a
+ * response with a TPM2_RC_COMMAND_CODE return for user-space.
+ */
+ if (ret == -EOPNOTSUPP) {
+ header->length = cpu_to_be32(sizeof(*header));
+ header->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
+ header->return_code = cpu_to_be32(TPM2_RC_COMMAND_CODE |
+ TSS2_RESMGR_TPM_RC_LAYER);
+ ret = sizeof(*header);
+ }
+ if (ret)
+ goto out_rc;
+
+ len = tpm_transmit(chip, buf, bufsiz);
+ if (len < 0)
+ ret = len;
+
+ if (!ret)
+ ret = tpm2_commit_space(chip, space, buf, &len);
+
+out_rc:
+ return ret ? ret : len;
+}
+
+static void tpm_dev_async_work(struct work_struct *work)
+{
+ struct file_priv *priv =
+ container_of(work, struct file_priv, async_work);
+ ssize_t ret;
+
+ mutex_lock(&priv->buffer_mutex);
+ priv->command_enqueued = false;
+ ret = tpm_dev_transmit(priv->chip, priv->space, priv->data_buffer,
+ sizeof(priv->data_buffer));
+ tpm_put_ops(priv->chip);
+ if (ret > 0) {
+ priv->response_length = ret;
+ mod_timer(&priv->user_read_timer, jiffies + (120 * HZ));
+ }
+ mutex_unlock(&priv->buffer_mutex);
+ wake_up_interruptible(&priv->async_wait);
+}
+
static void user_reader_timeout(struct timer_list *t)
{
struct file_priv *priv = from_timer(priv, t, user_read_timer);
@@ -29,27 +79,34 @@
pr_warn("TPM user space timeout is deprecated (pid=%d)\n",
task_tgid_nr(current));
- schedule_work(&priv->work);
+ schedule_work(&priv->timeout_work);
}
-static void timeout_work(struct work_struct *work)
+static void tpm_timeout_work(struct work_struct *work)
{
- struct file_priv *priv = container_of(work, struct file_priv, work);
+ struct file_priv *priv = container_of(work, struct file_priv,
+ timeout_work);
mutex_lock(&priv->buffer_mutex);
- priv->data_pending = 0;
+ priv->response_read = true;
+ priv->response_length = 0;
memset(priv->data_buffer, 0, sizeof(priv->data_buffer));
mutex_unlock(&priv->buffer_mutex);
+ wake_up_interruptible(&priv->async_wait);
}
void tpm_common_open(struct file *file, struct tpm_chip *chip,
- struct file_priv *priv)
+ struct file_priv *priv, struct tpm_space *space)
{
priv->chip = chip;
+ priv->space = space;
+ priv->response_read = true;
+
mutex_init(&priv->buffer_mutex);
timer_setup(&priv->user_read_timer, user_reader_timeout, 0);
- INIT_WORK(&priv->work, timeout_work);
-
+ INIT_WORK(&priv->timeout_work, tpm_timeout_work);
+ INIT_WORK(&priv->async_work, tpm_dev_async_work);
+ init_waitqueue_head(&priv->async_wait);
file->private_data = priv;
}
@@ -60,32 +117,46 @@
ssize_t ret_size = 0;
int rc;
- del_singleshot_timer_sync(&priv->user_read_timer);
- flush_work(&priv->work);
mutex_lock(&priv->buffer_mutex);
- if (priv->data_pending) {
- ret_size = min_t(ssize_t, size, priv->data_pending);
- rc = copy_to_user(buf, priv->data_buffer, ret_size);
- memset(priv->data_buffer, 0, priv->data_pending);
- if (rc)
- ret_size = -EFAULT;
+ if (priv->response_length) {
+ priv->response_read = true;
- priv->data_pending = 0;
+ ret_size = min_t(ssize_t, size, priv->response_length);
+ if (!ret_size) {
+ priv->response_length = 0;
+ goto out;
+ }
+
+ rc = copy_to_user(buf, priv->data_buffer + *off, ret_size);
+ if (rc) {
+ memset(priv->data_buffer, 0, TPM_BUFSIZE);
+ priv->response_length = 0;
+ ret_size = -EFAULT;
+ } else {
+ memset(priv->data_buffer + *off, 0, ret_size);
+ priv->response_length -= ret_size;
+ *off += ret_size;
+ }
}
+out:
+ if (!priv->response_length) {
+ *off = 0;
+ del_singleshot_timer_sync(&priv->user_read_timer);
+ flush_work(&priv->timeout_work);
+ }
mutex_unlock(&priv->buffer_mutex);
return ret_size;
}
ssize_t tpm_common_write(struct file *file, const char __user *buf,
- size_t size, loff_t *off, struct tpm_space *space)
+ size_t size, loff_t *off)
{
struct file_priv *priv = file->private_data;
- size_t in_size = size;
- ssize_t out_size;
+ int ret = 0;
- if (in_size > TPM_BUFSIZE)
+ if (size > TPM_BUFSIZE)
return -E2BIG;
mutex_lock(&priv->buffer_mutex);
@@ -94,21 +165,21 @@
* tpm_read or a user_read_timer timeout. This also prevents split
* buffered writes from blocking here.
*/
- if (priv->data_pending != 0) {
- mutex_unlock(&priv->buffer_mutex);
- return -EBUSY;
+ if ((!priv->response_read && priv->response_length) ||
+ priv->command_enqueued) {
+ ret = -EBUSY;
+ goto out;
}
- if (copy_from_user
- (priv->data_buffer, (void __user *) buf, in_size)) {
- mutex_unlock(&priv->buffer_mutex);
- return -EFAULT;
+ if (copy_from_user(priv->data_buffer, buf, size)) {
+ ret = -EFAULT;
+ goto out;
}
- if (in_size < 6 ||
- in_size < be32_to_cpu(*((__be32 *) (priv->data_buffer + 2)))) {
- mutex_unlock(&priv->buffer_mutex);
- return -EINVAL;
+ if (size < 6 ||
+ size < be32_to_cpu(*((__be32 *)(priv->data_buffer + 2)))) {
+ ret = -EINVAL;
+ goto out;
}
/* atomic tpm command send and result receive. We only hold the ops
@@ -116,25 +187,61 @@
* the char dev is held open.
*/
if (tpm_try_get_ops(priv->chip)) {
- mutex_unlock(&priv->buffer_mutex);
- return -EPIPE;
+ ret = -EPIPE;
+ goto out;
}
- out_size = tpm_transmit(priv->chip, space, priv->data_buffer,
- sizeof(priv->data_buffer), 0);
+ priv->response_length = 0;
+ priv->response_read = false;
+ *off = 0;
+
+ /*
+ * If in nonblocking mode schedule an async job to send
+ * the command return the size.
+ * In case of error the err code will be returned in
+ * the subsequent read call.
+ */
+ if (file->f_flags & O_NONBLOCK) {
+ priv->command_enqueued = true;
+ queue_work(tpm_dev_wq, &priv->async_work);
+ mutex_unlock(&priv->buffer_mutex);
+ return size;
+ }
+
+ ret = tpm_dev_transmit(priv->chip, priv->space, priv->data_buffer,
+ sizeof(priv->data_buffer));
tpm_put_ops(priv->chip);
- if (out_size < 0) {
- mutex_unlock(&priv->buffer_mutex);
- return out_size;
+
+ if (ret > 0) {
+ priv->response_length = ret;
+ mod_timer(&priv->user_read_timer, jiffies + (120 * HZ));
+ ret = size;
}
-
- priv->data_pending = out_size;
+out:
mutex_unlock(&priv->buffer_mutex);
+ return ret;
+}
- /* Set a timeout by which the reader must come claim the result */
- mod_timer(&priv->user_read_timer, jiffies + (120 * HZ));
+__poll_t tpm_common_poll(struct file *file, poll_table *wait)
+{
+ struct file_priv *priv = file->private_data;
+ __poll_t mask = 0;
- return in_size;
+ poll_wait(file, &priv->async_wait, wait);
+ mutex_lock(&priv->buffer_mutex);
+
+ /*
+ * The response_length indicates if there is still response
+ * (or part of it) to be consumed. Partial reads decrease it
+ * by the number of bytes read, and write resets it the zero.
+ */
+ if (priv->response_length)
+ mask = EPOLLIN | EPOLLRDNORM;
+ else
+ mask = EPOLLOUT | EPOLLWRNORM;
+
+ mutex_unlock(&priv->buffer_mutex);
+ return mask;
}
/*
@@ -142,8 +249,24 @@
*/
void tpm_common_release(struct file *file, struct file_priv *priv)
{
+ flush_work(&priv->async_work);
del_singleshot_timer_sync(&priv->user_read_timer);
- flush_work(&priv->work);
+ flush_work(&priv->timeout_work);
file->private_data = NULL;
- priv->data_pending = 0;
+ priv->response_length = 0;
+}
+
+int __init tpm_dev_common_init(void)
+{
+ tpm_dev_wq = alloc_workqueue("tpm_dev_wq", WQ_MEM_RECLAIM, 0);
+
+ return !tpm_dev_wq ? -ENOMEM : 0;
+}
+
+void __exit tpm_dev_common_exit(void)
+{
+ if (tpm_dev_wq) {
+ destroy_workqueue(tpm_dev_wq);
+ tpm_dev_wq = NULL;
+ }
}