Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 418 insertions, 0 deletions

diff --git a/drivers/crypto/atmel-i2c.c b/drivers/crypto/atmel-i2c.c
new file mode 100644
index 000000000..24bded47a
--- /dev/null
+++ b/drivers/crypto/atmel-i2c.c
@@ -0,0 +1,418 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Microchip / Atmel ECC (I2C) driver.
+ *
+ * Copyright (c) 2017, Microchip Technology Inc.
+ * Author: Tudor Ambarus
+ */
+
+#include <linux/bitrev.h>
+#include <linux/crc16.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include "atmel-i2c.h"
+
+static const struct {
+	u8 value;
+	const char *error_text;
+} error_list[] = {
+	{ 0x01, "CheckMac or Verify miscompare" },
+	{ 0x03, "Parse Error" },
+	{ 0x05, "ECC Fault" },
+	{ 0x0F, "Execution Error" },
+	{ 0xEE, "Watchdog about to expire" },
+	{ 0xFF, "CRC or other communication error" },
+};
+
+/**
+ * atmel_i2c_checksum() - Generate 16-bit CRC as required by ATMEL ECC.
+ * CRC16 verification of the count, opcode, param1, param2 and data bytes.
+ * The checksum is saved in little-endian format in the least significant
+ * two bytes of the command. CRC polynomial is 0x8005 and the initial register
+ * value should be zero.
+ *
+ * @cmd : structure used for communicating with the device.
+ */
+static void atmel_i2c_checksum(struct atmel_i2c_cmd *cmd)
+{
+	u8 *data = &cmd->count;
+	size_t len = cmd->count - CRC_SIZE;
+	__le16 *__crc16 = (__le16 *)(data + len);
+
+	*__crc16 = cpu_to_le16(bitrev16(crc16(0, data, len)));
+}
+
+void atmel_i2c_init_read_config_cmd(struct atmel_i2c_cmd *cmd)
+{
+	cmd->word_addr = COMMAND;
+	cmd->opcode = OPCODE_READ;
+	/*
+	 * Read the word from Configuration zone that contains the lock bytes
+	 * (UserExtra, Selector, LockValue, LockConfig).
+	 */
+	cmd->param1 = CONFIGURATION_ZONE;
+	cmd->param2 = cpu_to_le16(DEVICE_LOCK_ADDR);
+	cmd->count = READ_COUNT;
+
+	atmel_i2c_checksum(cmd);
+
+	cmd->msecs = MAX_EXEC_TIME_READ;
+	cmd->rxsize = READ_RSP_SIZE;
+}
+EXPORT_SYMBOL(atmel_i2c_init_read_config_cmd);
+
+int atmel_i2c_init_read_otp_cmd(struct atmel_i2c_cmd *cmd, u16 addr)
+{
+	if (addr >= OTP_ZONE_SIZE / 4)
+		return -EINVAL;
+
+	cmd->word_addr = COMMAND;
+	cmd->opcode = OPCODE_READ;
+	/*
+	 * Read the word from OTP zone that may contain e.g. serial
+	 * numbers or similar if persistently pre-initialized and locked
+	 */
+	cmd->param1 = OTP_ZONE;
+	cmd->param2 = cpu_to_le16(addr);
+	cmd->count = READ_COUNT;
+
+	atmel_i2c_checksum(cmd);
+
+	cmd->msecs = MAX_EXEC_TIME_READ;
+	cmd->rxsize = READ_RSP_SIZE;
+
+	return 0;
+}
+EXPORT_SYMBOL(atmel_i2c_init_read_otp_cmd);
+
+void atmel_i2c_init_random_cmd(struct atmel_i2c_cmd *cmd)
+{
+	cmd->word_addr = COMMAND;
+	cmd->opcode = OPCODE_RANDOM;
+	cmd->param1 = 0;
+	cmd->param2 = 0;
+	cmd->count = RANDOM_COUNT;
+
+	atmel_i2c_checksum(cmd);
+
+	cmd->msecs = MAX_EXEC_TIME_RANDOM;
+	cmd->rxsize = RANDOM_RSP_SIZE;
+}
+EXPORT_SYMBOL(atmel_i2c_init_random_cmd);
+
+void atmel_i2c_init_genkey_cmd(struct atmel_i2c_cmd *cmd, u16 keyid)
+{
+	cmd->word_addr = COMMAND;
+	cmd->count = GENKEY_COUNT;
+	cmd->opcode = OPCODE_GENKEY;
+	cmd->param1 = GENKEY_MODE_PRIVATE;
+	/* a random private key will be generated and stored in slot keyID */
+	cmd->param2 = cpu_to_le16(keyid);
+
+	atmel_i2c_checksum(cmd);
+
+	cmd->msecs = MAX_EXEC_TIME_GENKEY;
+	cmd->rxsize = GENKEY_RSP_SIZE;
+}
+EXPORT_SYMBOL(atmel_i2c_init_genkey_cmd);
+
+int atmel_i2c_init_ecdh_cmd(struct atmel_i2c_cmd *cmd,
+			    struct scatterlist *pubkey)
+{
+	size_t copied;
+
+	cmd->word_addr = COMMAND;
+	cmd->count = ECDH_COUNT;
+	cmd->opcode = OPCODE_ECDH;
+	cmd->param1 = ECDH_PREFIX_MODE;
+	/* private key slot */
+	cmd->param2 = cpu_to_le16(DATA_SLOT_2);
+
+	/*
+	 * The device only supports P-256. Its public key is encoded as
+	 * two 32-byte coordinates.
+	 */
+	copied = sg_copy_to_buffer(pubkey,
+				   sg_nents_for_len(pubkey,
+						    ATMEL_ECC_PUBKEY_SIZE),
+				   cmd->data, ATMEL_ECC_PUBKEY_SIZE);
+	if (copied != ATMEL_ECC_PUBKEY_SIZE)
+		return -EINVAL;
+
+	atmel_i2c_checksum(cmd);
+
+	cmd->msecs = MAX_EXEC_TIME_ECDH;
+	cmd->rxsize = ECDH_RSP_SIZE;
+
+	return 0;
+}
+EXPORT_SYMBOL(atmel_i2c_init_ecdh_cmd);
+
+/*
+ * After wake and after execution of a command, there will be error, status, or
+ * result bytes in the device's output register that can be retrieved by the
+ * system. When the length of that group is four bytes, the codes returned are
+ * detailed in error_list.
+ */
+static int atmel_i2c_status(struct device *dev, u8 *status)
+{
+	size_t err_list_len = ARRAY_SIZE(error_list);
+	int i;
+	u8 err_id = status[1];
+
+	if (*status != STATUS_SIZE)
+		return 0;
+
+	if (err_id == STATUS_WAKE_SUCCESSFUL || err_id == STATUS_NOERR)
+		return 0;
+
+	for (i = 0; i < err_list_len; i++)
+		if (error_list[i].value == err_id)
+			break;
+
+	/* if err_id is not in the error_list then ignore it */
+	if (i != err_list_len) {
+		dev_err(dev, "%02x: %s:\n", err_id, error_list[i].error_text);
+		return err_id;
+	}
+
+	return 0;
+}
+
+static int atmel_i2c_wakeup(struct i2c_client *client)
+{
+	struct atmel_i2c_client_priv *i2c_priv = i2c_get_clientdata(client);
+	u8 status[STATUS_RSP_SIZE];
+	int ret;
+
+	/*
+	 * The device ignores any levels or transitions on the SCL pin when the
+	 * device is idle, asleep or during waking up. Don't check for error
+	 * when waking up the device.
+	 */
+	i2c_transfer_buffer_flags(client, i2c_priv->wake_token,
+				i2c_priv->wake_token_sz, I2C_M_IGNORE_NAK);
+
+	/*
+	 * Wait to wake the device. Typical execution times for ecdh and genkey
+	 * are around tens of milliseconds. Delta is chosen to 50 microseconds.
+	 */
+	usleep_range(TWHI_MIN, TWHI_MAX);
+
+	ret = i2c_master_recv(client, status, STATUS_SIZE);
+	if (ret < 0)
+		return ret;
+
+	return atmel_i2c_status(&client->dev, status);
+}
+
+static int atmel_i2c_sleep(struct i2c_client *client)
+{
+	u8 sleep = SLEEP_TOKEN;
+
+	return i2c_master_send(client, &sleep, 1);
+}
+
+/*
+ * atmel_i2c_send_receive() - send a command to the device and receive its
+ *                            response.
+ * @client: i2c client device
+ * @cmd   : structure used to communicate with the device
+ *
+ * After the device receives a Wake token, a watchdog counter starts within the
+ * device. After the watchdog timer expires, the device enters sleep mode
+ * regardless of whether some I/O transmission or command execution is in
+ * progress. If a command is attempted when insufficient time remains prior to
+ * watchdog timer execution, the device will return the watchdog timeout error
+ * code without attempting to execute the command. There is no way to reset the
+ * counter other than to put the device into sleep or idle mode and then
+ * wake it up again.
+ */
+int atmel_i2c_send_receive(struct i2c_client *client, struct atmel_i2c_cmd *cmd)
+{
+	struct atmel_i2c_client_priv *i2c_priv = i2c_get_clientdata(client);
+	int ret;
+
+	mutex_lock(&i2c_priv->lock);
+
+	ret = atmel_i2c_wakeup(client);
+	if (ret)
+		goto err;
+
+	/* send the command */
+	ret = i2c_master_send(client, (u8 *)cmd, cmd->count + WORD_ADDR_SIZE);
+	if (ret < 0)
+		goto err;
+
+	/* delay the appropriate amount of time for command to execute */
+	msleep(cmd->msecs);
+
+	/* receive the response */
+	ret = i2c_master_recv(client, cmd->data, cmd->rxsize);
+	if (ret < 0)
+		goto err;
+
+	/* put the device into low-power mode */
+	ret = atmel_i2c_sleep(client);
+	if (ret < 0)
+		goto err;
+
+	mutex_unlock(&i2c_priv->lock);
+	return atmel_i2c_status(&client->dev, cmd->data);
+err:
+	mutex_unlock(&i2c_priv->lock);
+	return ret;
+}
+EXPORT_SYMBOL(atmel_i2c_send_receive);
+
+static void atmel_i2c_work_handler(struct work_struct *work)
+{
+	struct atmel_i2c_work_data *work_data =
+			container_of(work, struct atmel_i2c_work_data, work);
+	struct atmel_i2c_cmd *cmd = &work_data->cmd;
+	struct i2c_client *client = work_data->client;
+	int status;
+
+	status = atmel_i2c_send_receive(client, cmd);
+	work_data->cbk(work_data, work_data->areq, status);
+}
+
+static struct workqueue_struct *atmel_wq;
+
+void atmel_i2c_enqueue(struct atmel_i2c_work_data *work_data,
+		       void (*cbk)(struct atmel_i2c_work_data *work_data,
+				   void *areq, int status),
+		       void *areq)
+{
+	work_data->cbk = cbk;
+	work_data->areq = areq;
+
+	INIT_WORK(&work_data->work, atmel_i2c_work_handler);
+	queue_work(atmel_wq, &work_data->work);
+}
+EXPORT_SYMBOL(atmel_i2c_enqueue);
+
+void atmel_i2c_flush_queue(void)
+{
+	flush_workqueue(atmel_wq);
+}
+EXPORT_SYMBOL(atmel_i2c_flush_queue);
+
+static inline size_t atmel_i2c_wake_token_sz(u32 bus_clk_rate)
+{
+	u32 no_of_bits = DIV_ROUND_UP(TWLO_USEC * bus_clk_rate, USEC_PER_SEC);
+
+	/* return the size of the wake_token in bytes */
+	return DIV_ROUND_UP(no_of_bits, 8);
+}
+
+static int device_sanity_check(struct i2c_client *client)
+{
+	struct atmel_i2c_cmd *cmd;
+	int ret;
+
+	cmd = kmalloc_obj(*cmd);
+	if (!cmd)
+		return -ENOMEM;
+
+	atmel_i2c_init_read_config_cmd(cmd);
+
+	ret = atmel_i2c_send_receive(client, cmd);
+	if (ret)
+		goto free_cmd;
+
+	/*
+	 * It is vital that the Configuration, Data and OTP zones be locked
+	 * prior to release into the field of the system containing the device.
+	 * Failure to lock these zones may permit modification of any secret
+	 * keys and may lead to other security problems.
+	 */
+	if (cmd->data[LOCK_CONFIG_IDX] || cmd->data[LOCK_VALUE_IDX]) {
+		dev_err(&client->dev, "Configuration or Data and OTP zones are unlocked!\n");
+		ret = -ENOTSUPP;
+	}
+
+	/* fall through */
+free_cmd:
+	kfree(cmd);
+	return ret;
+}
+
+int atmel_i2c_probe(struct i2c_client *client)
+{
+	struct atmel_i2c_client_priv *i2c_priv;
+	struct device *dev = &client->dev;
+	int ret;
+	u32 bus_clk_rate;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+		dev_err(dev, "I2C_FUNC_I2C not supported\n");
+		return -ENODEV;
+	}
+
+	bus_clk_rate = i2c_acpi_find_bus_speed(&client->adapter->dev);
+	if (!bus_clk_rate) {
+		ret = device_property_read_u32(&client->adapter->dev,
+					       "clock-frequency", &bus_clk_rate);
+		if (ret) {
+			dev_err(dev, "failed to read clock-frequency property\n");
+			return ret;
+		}
+	}
+
+	if (bus_clk_rate > I2C_MAX_FAST_MODE_PLUS_FREQ) {
+		dev_err(dev, "%u exceeds maximum supported clock frequency (1MHz)\n",
+			bus_clk_rate);
+		return -EINVAL;
+	}
+
+	i2c_priv = devm_kmalloc(dev, sizeof(*i2c_priv), GFP_KERNEL);
+	if (!i2c_priv)
+		return -ENOMEM;
+
+	i2c_priv->client = client;
+	mutex_init(&i2c_priv->lock);
+
+	/*
+	 * WAKE_TOKEN_MAX_SIZE was calculated for the maximum bus_clk_rate -
+	 * 1MHz. The previous bus_clk_rate check ensures us that wake_token_sz
+	 * will always be smaller than or equal to WAKE_TOKEN_MAX_SIZE.
+	 */
+	i2c_priv->wake_token_sz = atmel_i2c_wake_token_sz(bus_clk_rate);
+
+	memset(i2c_priv->wake_token, 0, sizeof(i2c_priv->wake_token));
+
+	atomic_set(&i2c_priv->tfm_count, 0);
+
+	i2c_set_clientdata(client, i2c_priv);
+
+	return device_sanity_check(client);
+}
+EXPORT_SYMBOL(atmel_i2c_probe);
+
+static int __init atmel_i2c_init(void)
+{
+	atmel_wq = alloc_workqueue("atmel_wq", WQ_PERCPU, 0);
+	return atmel_wq ? 0 : -ENOMEM;
+}
+
+static void __exit atmel_i2c_exit(void)
+{
+	destroy_workqueue(atmel_wq);
+}
+
+module_init(atmel_i2c_init);
+module_exit(atmel_i2c_exit);
+
+MODULE_AUTHOR("Tudor Ambarus");
+MODULE_DESCRIPTION("Microchip / Atmel ECC (I2C) driver");
+MODULE_LICENSE("GPL v2");