linux_dsm_epyc7002/net/nfc/nci/core.c
Dan Carpenter 8ebafde00e NFC: use after free on error
We returned a freed variable on some error paths when the intent was
to return a NULL.  Part of the reason this was missed was that the
code was confusing because it had too many gotos so I removed them
and simplified the flow a bit.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Lauro Ramos Venancio <lauro.venancio@openbossa.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-09-27 14:34:10 -04:00

798 lines
18 KiB
C

/*
* The NFC Controller Interface is the communication protocol between an
* NFC Controller (NFCC) and a Device Host (DH).
*
* Copyright (C) 2011 Texas Instruments, Inc.
*
* Written by Ilan Elias <ilane@ti.com>
*
* Acknowledgements:
* This file is based on hci_core.c, which was written
* by Maxim Krasnyansky.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <linux/types.h>
#include <linux/workqueue.h>
#include <linux/completion.h>
#include <linux/sched.h>
#include <linux/bitops.h>
#include <linux/skbuff.h>
#include "../nfc.h"
#include <net/nfc/nci.h>
#include <net/nfc/nci_core.h>
#include <linux/nfc.h>
static void nci_cmd_work(struct work_struct *work);
static void nci_rx_work(struct work_struct *work);
static void nci_tx_work(struct work_struct *work);
/* ---- NCI requests ---- */
void nci_req_complete(struct nci_dev *ndev, int result)
{
if (ndev->req_status == NCI_REQ_PEND) {
ndev->req_result = result;
ndev->req_status = NCI_REQ_DONE;
complete(&ndev->req_completion);
}
}
static void nci_req_cancel(struct nci_dev *ndev, int err)
{
if (ndev->req_status == NCI_REQ_PEND) {
ndev->req_result = err;
ndev->req_status = NCI_REQ_CANCELED;
complete(&ndev->req_completion);
}
}
/* Execute request and wait for completion. */
static int __nci_request(struct nci_dev *ndev,
void (*req)(struct nci_dev *ndev, unsigned long opt),
unsigned long opt,
__u32 timeout)
{
int rc = 0;
unsigned long completion_rc;
ndev->req_status = NCI_REQ_PEND;
init_completion(&ndev->req_completion);
req(ndev, opt);
completion_rc = wait_for_completion_interruptible_timeout(
&ndev->req_completion,
timeout);
nfc_dbg("wait_for_completion return %ld", completion_rc);
if (completion_rc > 0) {
switch (ndev->req_status) {
case NCI_REQ_DONE:
rc = nci_to_errno(ndev->req_result);
break;
case NCI_REQ_CANCELED:
rc = -ndev->req_result;
break;
default:
rc = -ETIMEDOUT;
break;
}
} else {
nfc_err("wait_for_completion_interruptible_timeout failed %ld",
completion_rc);
rc = ((completion_rc == 0) ? (-ETIMEDOUT) : (completion_rc));
}
ndev->req_status = ndev->req_result = 0;
return rc;
}
static inline int nci_request(struct nci_dev *ndev,
void (*req)(struct nci_dev *ndev, unsigned long opt),
unsigned long opt, __u32 timeout)
{
int rc;
if (!test_bit(NCI_UP, &ndev->flags))
return -ENETDOWN;
/* Serialize all requests */
mutex_lock(&ndev->req_lock);
rc = __nci_request(ndev, req, opt, timeout);
mutex_unlock(&ndev->req_lock);
return rc;
}
static void nci_reset_req(struct nci_dev *ndev, unsigned long opt)
{
nci_send_cmd(ndev, NCI_OP_CORE_RESET_CMD, 0, NULL);
}
static void nci_init_req(struct nci_dev *ndev, unsigned long opt)
{
nci_send_cmd(ndev, NCI_OP_CORE_INIT_CMD, 0, NULL);
}
static void nci_init_complete_req(struct nci_dev *ndev, unsigned long opt)
{
struct nci_core_conn_create_cmd conn_cmd;
struct nci_rf_disc_map_cmd cmd;
struct disc_map_config *cfg = cmd.mapping_configs;
__u8 *num = &cmd.num_mapping_configs;
int i;
/* create static rf connection */
conn_cmd.target_handle = 0;
conn_cmd.num_target_specific_params = 0;
nci_send_cmd(ndev, NCI_OP_CORE_CONN_CREATE_CMD, 2, &conn_cmd);
/* set rf mapping configurations */
*num = 0;
/* by default mapping is set to NCI_RF_INTERFACE_FRAME */
for (i = 0; i < ndev->num_supported_rf_interfaces; i++) {
if (ndev->supported_rf_interfaces[i] ==
NCI_RF_INTERFACE_ISO_DEP) {
cfg[*num].rf_protocol = NCI_RF_PROTOCOL_ISO_DEP;
cfg[*num].mode = NCI_DISC_MAP_MODE_BOTH;
cfg[*num].rf_interface_type = NCI_RF_INTERFACE_ISO_DEP;
(*num)++;
} else if (ndev->supported_rf_interfaces[i] ==
NCI_RF_INTERFACE_NFC_DEP) {
cfg[*num].rf_protocol = NCI_RF_PROTOCOL_NFC_DEP;
cfg[*num].mode = NCI_DISC_MAP_MODE_BOTH;
cfg[*num].rf_interface_type = NCI_RF_INTERFACE_NFC_DEP;
(*num)++;
}
if (*num == NCI_MAX_NUM_MAPPING_CONFIGS)
break;
}
nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_MAP_CMD,
(1 + ((*num)*sizeof(struct disc_map_config))),
&cmd);
}
static void nci_rf_discover_req(struct nci_dev *ndev, unsigned long opt)
{
struct nci_rf_disc_cmd cmd;
__u32 protocols = opt;
cmd.num_disc_configs = 0;
if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
(protocols & NFC_PROTO_JEWEL_MASK
|| protocols & NFC_PROTO_MIFARE_MASK
|| protocols & NFC_PROTO_ISO14443_MASK
|| protocols & NFC_PROTO_NFC_DEP_MASK)) {
cmd.disc_configs[cmd.num_disc_configs].type =
NCI_DISCOVERY_TYPE_POLL_A_PASSIVE;
cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
cmd.num_disc_configs++;
}
if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
(protocols & NFC_PROTO_ISO14443_MASK)) {
cmd.disc_configs[cmd.num_disc_configs].type =
NCI_DISCOVERY_TYPE_POLL_B_PASSIVE;
cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
cmd.num_disc_configs++;
}
if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
(protocols & NFC_PROTO_FELICA_MASK
|| protocols & NFC_PROTO_NFC_DEP_MASK)) {
cmd.disc_configs[cmd.num_disc_configs].type =
NCI_DISCOVERY_TYPE_POLL_F_PASSIVE;
cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
cmd.num_disc_configs++;
}
nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_CMD,
(1 + (cmd.num_disc_configs*sizeof(struct disc_config))),
&cmd);
}
static void nci_rf_deactivate_req(struct nci_dev *ndev, unsigned long opt)
{
struct nci_rf_deactivate_cmd cmd;
cmd.type = NCI_DEACTIVATE_TYPE_IDLE_MODE;
nci_send_cmd(ndev, NCI_OP_RF_DEACTIVATE_CMD,
sizeof(struct nci_rf_deactivate_cmd),
&cmd);
}
static int nci_open_device(struct nci_dev *ndev)
{
int rc = 0;
mutex_lock(&ndev->req_lock);
if (test_bit(NCI_UP, &ndev->flags)) {
rc = -EALREADY;
goto done;
}
if (ndev->ops->open(ndev)) {
rc = -EIO;
goto done;
}
atomic_set(&ndev->cmd_cnt, 1);
set_bit(NCI_INIT, &ndev->flags);
rc = __nci_request(ndev, nci_reset_req, 0,
msecs_to_jiffies(NCI_RESET_TIMEOUT));
if (!rc) {
rc = __nci_request(ndev, nci_init_req, 0,
msecs_to_jiffies(NCI_INIT_TIMEOUT));
}
if (!rc) {
rc = __nci_request(ndev, nci_init_complete_req, 0,
msecs_to_jiffies(NCI_INIT_TIMEOUT));
}
clear_bit(NCI_INIT, &ndev->flags);
if (!rc) {
set_bit(NCI_UP, &ndev->flags);
} else {
/* Init failed, cleanup */
skb_queue_purge(&ndev->cmd_q);
skb_queue_purge(&ndev->rx_q);
skb_queue_purge(&ndev->tx_q);
ndev->ops->close(ndev);
ndev->flags = 0;
}
done:
mutex_unlock(&ndev->req_lock);
return rc;
}
static int nci_close_device(struct nci_dev *ndev)
{
nci_req_cancel(ndev, ENODEV);
mutex_lock(&ndev->req_lock);
if (!test_and_clear_bit(NCI_UP, &ndev->flags)) {
del_timer_sync(&ndev->cmd_timer);
mutex_unlock(&ndev->req_lock);
return 0;
}
/* Drop RX and TX queues */
skb_queue_purge(&ndev->rx_q);
skb_queue_purge(&ndev->tx_q);
/* Flush RX and TX wq */
flush_workqueue(ndev->rx_wq);
flush_workqueue(ndev->tx_wq);
/* Reset device */
skb_queue_purge(&ndev->cmd_q);
atomic_set(&ndev->cmd_cnt, 1);
set_bit(NCI_INIT, &ndev->flags);
__nci_request(ndev, nci_reset_req, 0,
msecs_to_jiffies(NCI_RESET_TIMEOUT));
clear_bit(NCI_INIT, &ndev->flags);
/* Flush cmd wq */
flush_workqueue(ndev->cmd_wq);
/* After this point our queues are empty
* and no works are scheduled. */
ndev->ops->close(ndev);
/* Clear flags */
ndev->flags = 0;
mutex_unlock(&ndev->req_lock);
return 0;
}
/* NCI command timer function */
static void nci_cmd_timer(unsigned long arg)
{
struct nci_dev *ndev = (void *) arg;
nfc_dbg("entry");
atomic_set(&ndev->cmd_cnt, 1);
queue_work(ndev->cmd_wq, &ndev->cmd_work);
}
static int nci_dev_up(struct nfc_dev *nfc_dev)
{
struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
nfc_dbg("entry");
return nci_open_device(ndev);
}
static int nci_dev_down(struct nfc_dev *nfc_dev)
{
struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
nfc_dbg("entry");
return nci_close_device(ndev);
}
static int nci_start_poll(struct nfc_dev *nfc_dev, __u32 protocols)
{
struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
int rc;
nfc_dbg("entry");
if (test_bit(NCI_DISCOVERY, &ndev->flags)) {
nfc_err("unable to start poll, since poll is already active");
return -EBUSY;
}
if (ndev->target_active_prot) {
nfc_err("there is an active target");
return -EBUSY;
}
if (test_bit(NCI_POLL_ACTIVE, &ndev->flags)) {
nfc_dbg("target is active, implicitly deactivate...");
rc = nci_request(ndev, nci_rf_deactivate_req, 0,
msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT));
if (rc)
return -EBUSY;
}
rc = nci_request(ndev, nci_rf_discover_req, protocols,
msecs_to_jiffies(NCI_RF_DISC_TIMEOUT));
if (!rc)
ndev->poll_prots = protocols;
return rc;
}
static void nci_stop_poll(struct nfc_dev *nfc_dev)
{
struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
nfc_dbg("entry");
if (!test_bit(NCI_DISCOVERY, &ndev->flags)) {
nfc_err("unable to stop poll, since poll is not active");
return;
}
nci_request(ndev, nci_rf_deactivate_req, 0,
msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT));
}
static int nci_activate_target(struct nfc_dev *nfc_dev, __u32 target_idx,
__u32 protocol)
{
struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
nfc_dbg("entry, target_idx %d, protocol 0x%x", target_idx, protocol);
if (!test_bit(NCI_POLL_ACTIVE, &ndev->flags)) {
nfc_err("there is no available target to activate");
return -EINVAL;
}
if (ndev->target_active_prot) {
nfc_err("there is already an active target");
return -EBUSY;
}
if (!(ndev->target_available_prots & (1 << protocol))) {
nfc_err("target does not support the requested protocol 0x%x",
protocol);
return -EINVAL;
}
ndev->target_active_prot = protocol;
ndev->target_available_prots = 0;
return 0;
}
static void nci_deactivate_target(struct nfc_dev *nfc_dev, __u32 target_idx)
{
struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
nfc_dbg("entry, target_idx %d", target_idx);
if (!ndev->target_active_prot) {
nfc_err("unable to deactivate target, no active target");
return;
}
ndev->target_active_prot = 0;
if (test_bit(NCI_POLL_ACTIVE, &ndev->flags)) {
nci_request(ndev, nci_rf_deactivate_req, 0,
msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT));
}
}
static int nci_data_exchange(struct nfc_dev *nfc_dev, __u32 target_idx,
struct sk_buff *skb,
data_exchange_cb_t cb,
void *cb_context)
{
struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
int rc;
nfc_dbg("entry, target_idx %d, len %d", target_idx, skb->len);
if (!ndev->target_active_prot) {
nfc_err("unable to exchange data, no active target");
return -EINVAL;
}
if (test_and_set_bit(NCI_DATA_EXCHANGE, &ndev->flags))
return -EBUSY;
/* store cb and context to be used on receiving data */
ndev->data_exchange_cb = cb;
ndev->data_exchange_cb_context = cb_context;
rc = nci_send_data(ndev, ndev->conn_id, skb);
if (rc)
clear_bit(NCI_DATA_EXCHANGE, &ndev->flags);
return rc;
}
static struct nfc_ops nci_nfc_ops = {
.dev_up = nci_dev_up,
.dev_down = nci_dev_down,
.start_poll = nci_start_poll,
.stop_poll = nci_stop_poll,
.activate_target = nci_activate_target,
.deactivate_target = nci_deactivate_target,
.data_exchange = nci_data_exchange,
};
/* ---- Interface to NCI drivers ---- */
/**
* nci_allocate_device - allocate a new nci device
*
* @ops: device operations
* @supported_protocols: NFC protocols supported by the device
*/
struct nci_dev *nci_allocate_device(struct nci_ops *ops,
__u32 supported_protocols,
int tx_headroom,
int tx_tailroom)
{
struct nci_dev *ndev;
nfc_dbg("entry, supported_protocols 0x%x", supported_protocols);
if (!ops->open || !ops->close || !ops->send)
return NULL;
if (!supported_protocols)
return NULL;
ndev = kzalloc(sizeof(struct nci_dev), GFP_KERNEL);
if (!ndev)
return NULL;
ndev->ops = ops;
ndev->tx_headroom = tx_headroom;
ndev->tx_tailroom = tx_tailroom;
ndev->nfc_dev = nfc_allocate_device(&nci_nfc_ops,
supported_protocols,
tx_headroom + NCI_DATA_HDR_SIZE,
tx_tailroom);
if (!ndev->nfc_dev)
goto free_exit;
nfc_set_drvdata(ndev->nfc_dev, ndev);
return ndev;
free_exit:
kfree(ndev);
return NULL;
}
EXPORT_SYMBOL(nci_allocate_device);
/**
* nci_free_device - deallocate nci device
*
* @ndev: The nci device to deallocate
*/
void nci_free_device(struct nci_dev *ndev)
{
nfc_dbg("entry");
nfc_free_device(ndev->nfc_dev);
kfree(ndev);
}
EXPORT_SYMBOL(nci_free_device);
/**
* nci_register_device - register a nci device in the nfc subsystem
*
* @dev: The nci device to register
*/
int nci_register_device(struct nci_dev *ndev)
{
int rc;
struct device *dev = &ndev->nfc_dev->dev;
char name[32];
nfc_dbg("entry");
rc = nfc_register_device(ndev->nfc_dev);
if (rc)
goto exit;
ndev->flags = 0;
INIT_WORK(&ndev->cmd_work, nci_cmd_work);
snprintf(name, sizeof(name), "%s_nci_cmd_wq", dev_name(dev));
ndev->cmd_wq = create_singlethread_workqueue(name);
if (!ndev->cmd_wq) {
rc = -ENOMEM;
goto unreg_exit;
}
INIT_WORK(&ndev->rx_work, nci_rx_work);
snprintf(name, sizeof(name), "%s_nci_rx_wq", dev_name(dev));
ndev->rx_wq = create_singlethread_workqueue(name);
if (!ndev->rx_wq) {
rc = -ENOMEM;
goto destroy_cmd_wq_exit;
}
INIT_WORK(&ndev->tx_work, nci_tx_work);
snprintf(name, sizeof(name), "%s_nci_tx_wq", dev_name(dev));
ndev->tx_wq = create_singlethread_workqueue(name);
if (!ndev->tx_wq) {
rc = -ENOMEM;
goto destroy_rx_wq_exit;
}
skb_queue_head_init(&ndev->cmd_q);
skb_queue_head_init(&ndev->rx_q);
skb_queue_head_init(&ndev->tx_q);
setup_timer(&ndev->cmd_timer, nci_cmd_timer,
(unsigned long) ndev);
mutex_init(&ndev->req_lock);
goto exit;
destroy_rx_wq_exit:
destroy_workqueue(ndev->rx_wq);
destroy_cmd_wq_exit:
destroy_workqueue(ndev->cmd_wq);
unreg_exit:
nfc_unregister_device(ndev->nfc_dev);
exit:
return rc;
}
EXPORT_SYMBOL(nci_register_device);
/**
* nci_unregister_device - unregister a nci device in the nfc subsystem
*
* @dev: The nci device to unregister
*/
void nci_unregister_device(struct nci_dev *ndev)
{
nfc_dbg("entry");
nci_close_device(ndev);
destroy_workqueue(ndev->cmd_wq);
destroy_workqueue(ndev->rx_wq);
destroy_workqueue(ndev->tx_wq);
nfc_unregister_device(ndev->nfc_dev);
}
EXPORT_SYMBOL(nci_unregister_device);
/**
* nci_recv_frame - receive frame from NCI drivers
*
* @skb: The sk_buff to receive
*/
int nci_recv_frame(struct sk_buff *skb)
{
struct nci_dev *ndev = (struct nci_dev *) skb->dev;
nfc_dbg("entry, len %d", skb->len);
if (!ndev || (!test_bit(NCI_UP, &ndev->flags)
&& !test_bit(NCI_INIT, &ndev->flags))) {
kfree_skb(skb);
return -ENXIO;
}
/* Queue frame for rx worker thread */
skb_queue_tail(&ndev->rx_q, skb);
queue_work(ndev->rx_wq, &ndev->rx_work);
return 0;
}
EXPORT_SYMBOL(nci_recv_frame);
static int nci_send_frame(struct sk_buff *skb)
{
struct nci_dev *ndev = (struct nci_dev *) skb->dev;
nfc_dbg("entry, len %d", skb->len);
if (!ndev) {
kfree_skb(skb);
return -ENODEV;
}
/* Get rid of skb owner, prior to sending to the driver. */
skb_orphan(skb);
return ndev->ops->send(skb);
}
/* Send NCI command */
int nci_send_cmd(struct nci_dev *ndev, __u16 opcode, __u8 plen, void *payload)
{
struct nci_ctrl_hdr *hdr;
struct sk_buff *skb;
nfc_dbg("entry, opcode 0x%x, plen %d", opcode, plen);
skb = nci_skb_alloc(ndev, (NCI_CTRL_HDR_SIZE + plen), GFP_KERNEL);
if (!skb) {
nfc_err("no memory for command");
return -ENOMEM;
}
hdr = (struct nci_ctrl_hdr *) skb_put(skb, NCI_CTRL_HDR_SIZE);
hdr->gid = nci_opcode_gid(opcode);
hdr->oid = nci_opcode_oid(opcode);
hdr->plen = plen;
nci_mt_set((__u8 *)hdr, NCI_MT_CMD_PKT);
nci_pbf_set((__u8 *)hdr, NCI_PBF_LAST);
if (plen)
memcpy(skb_put(skb, plen), payload, plen);
skb->dev = (void *) ndev;
skb_queue_tail(&ndev->cmd_q, skb);
queue_work(ndev->cmd_wq, &ndev->cmd_work);
return 0;
}
/* ---- NCI TX Data worker thread ---- */
static void nci_tx_work(struct work_struct *work)
{
struct nci_dev *ndev = container_of(work, struct nci_dev, tx_work);
struct sk_buff *skb;
nfc_dbg("entry, credits_cnt %d", atomic_read(&ndev->credits_cnt));
/* Send queued tx data */
while (atomic_read(&ndev->credits_cnt)) {
skb = skb_dequeue(&ndev->tx_q);
if (!skb)
return;
atomic_dec(&ndev->credits_cnt);
nfc_dbg("NCI TX: MT=data, PBF=%d, conn_id=%d, plen=%d",
nci_pbf(skb->data),
nci_conn_id(skb->data),
nci_plen(skb->data));
nci_send_frame(skb);
}
}
/* ----- NCI RX worker thread (data & control) ----- */
static void nci_rx_work(struct work_struct *work)
{
struct nci_dev *ndev = container_of(work, struct nci_dev, rx_work);
struct sk_buff *skb;
while ((skb = skb_dequeue(&ndev->rx_q))) {
/* Process frame */
switch (nci_mt(skb->data)) {
case NCI_MT_RSP_PKT:
nci_rsp_packet(ndev, skb);
break;
case NCI_MT_NTF_PKT:
nci_ntf_packet(ndev, skb);
break;
case NCI_MT_DATA_PKT:
nci_rx_data_packet(ndev, skb);
break;
default:
nfc_err("unknown MT 0x%x", nci_mt(skb->data));
kfree_skb(skb);
break;
}
}
}
/* ----- NCI TX CMD worker thread ----- */
static void nci_cmd_work(struct work_struct *work)
{
struct nci_dev *ndev = container_of(work, struct nci_dev, cmd_work);
struct sk_buff *skb;
nfc_dbg("entry, cmd_cnt %d", atomic_read(&ndev->cmd_cnt));
/* Send queued command */
if (atomic_read(&ndev->cmd_cnt)) {
skb = skb_dequeue(&ndev->cmd_q);
if (!skb)
return;
atomic_dec(&ndev->cmd_cnt);
nfc_dbg("NCI TX: MT=cmd, PBF=%d, GID=0x%x, OID=0x%x, plen=%d",
nci_pbf(skb->data),
nci_opcode_gid(nci_opcode(skb->data)),
nci_opcode_oid(nci_opcode(skb->data)),
nci_plen(skb->data));
nci_send_frame(skb);
mod_timer(&ndev->cmd_timer,
jiffies + msecs_to_jiffies(NCI_CMD_TIMEOUT));
}
}