From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- net/mac802154/tx.c | 240 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 240 insertions(+) create mode 100644 net/mac802154/tx.c (limited to 'net/mac802154/tx.c') diff --git a/net/mac802154/tx.c b/net/mac802154/tx.c new file mode 100644 index 000000000..4d13f18f6 --- /dev/null +++ b/net/mac802154/tx.c @@ -0,0 +1,240 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright 2007-2012 Siemens AG + * + * Written by: + * Dmitry Eremin-Solenikov + * Sergey Lapin + * Maxim Gorbachyov + * Alexander Smirnov + */ + +#include +#include +#include +#include + +#include +#include +#include +#include + +#include "ieee802154_i.h" +#include "driver-ops.h" + +void ieee802154_xmit_sync_worker(struct work_struct *work) +{ + struct ieee802154_local *local = + container_of(work, struct ieee802154_local, sync_tx_work); + struct sk_buff *skb = local->tx_skb; + struct net_device *dev = skb->dev; + int res; + + res = drv_xmit_sync(local, skb); + if (res) + goto err_tx; + + DEV_STATS_INC(dev, tx_packets); + DEV_STATS_ADD(dev, tx_bytes, skb->len); + + ieee802154_xmit_complete(&local->hw, skb, false); + + return; + +err_tx: + /* Restart the netif queue on each sub_if_data object. */ + ieee802154_release_queue(local); + if (atomic_dec_and_test(&local->phy->ongoing_txs)) + wake_up(&local->phy->sync_txq); + kfree_skb(skb); + netdev_dbg(dev, "transmission failed\n"); +} + +static netdev_tx_t +ieee802154_tx(struct ieee802154_local *local, struct sk_buff *skb) +{ + struct net_device *dev = skb->dev; + int ret; + + if (!(local->hw.flags & IEEE802154_HW_TX_OMIT_CKSUM)) { + struct sk_buff *nskb; + u16 crc; + + if (unlikely(skb_tailroom(skb) < IEEE802154_FCS_LEN)) { + nskb = skb_copy_expand(skb, 0, IEEE802154_FCS_LEN, + GFP_ATOMIC); + if (likely(nskb)) { + consume_skb(skb); + skb = nskb; + } else { + goto err_free_skb; + } + } + + crc = crc_ccitt(0, skb->data, skb->len); + put_unaligned_le16(crc, skb_put(skb, 2)); + } + + /* Stop the netif queue on each sub_if_data object. */ + ieee802154_hold_queue(local); + atomic_inc(&local->phy->ongoing_txs); + + /* Drivers should preferably implement the async callback. In some rare + * cases they only provide a sync callback which we will use as a + * fallback. + */ + if (local->ops->xmit_async) { + unsigned int len = skb->len; + + ret = drv_xmit_async(local, skb); + if (ret) + goto err_wake_netif_queue; + + DEV_STATS_INC(dev, tx_packets); + DEV_STATS_ADD(dev, tx_bytes, len); + } else { + local->tx_skb = skb; + queue_work(local->workqueue, &local->sync_tx_work); + } + + return NETDEV_TX_OK; + +err_wake_netif_queue: + ieee802154_release_queue(local); + if (atomic_dec_and_test(&local->phy->ongoing_txs)) + wake_up(&local->phy->sync_txq); +err_free_skb: + kfree_skb(skb); + return NETDEV_TX_OK; +} + +static int ieee802154_sync_queue(struct ieee802154_local *local) +{ + int ret; + + ieee802154_hold_queue(local); + ieee802154_disable_queue(local); + wait_event(local->phy->sync_txq, !atomic_read(&local->phy->ongoing_txs)); + ret = local->tx_result; + ieee802154_release_queue(local); + + return ret; +} + +int ieee802154_sync_and_hold_queue(struct ieee802154_local *local) +{ + int ret; + + ieee802154_hold_queue(local); + ret = ieee802154_sync_queue(local); + set_bit(WPAN_PHY_FLAG_STATE_QUEUE_STOPPED, &local->phy->flags); + + return ret; +} + +int ieee802154_mlme_op_pre(struct ieee802154_local *local) +{ + return ieee802154_sync_and_hold_queue(local); +} + +int ieee802154_mlme_tx_locked(struct ieee802154_local *local, + struct ieee802154_sub_if_data *sdata, + struct sk_buff *skb) +{ + /* Avoid possible calls to ->ndo_stop() when we asynchronously perform + * MLME transmissions. + */ + ASSERT_RTNL(); + + /* Ensure the device was not stopped, otherwise error out */ + if (!local->open_count) + return -ENETDOWN; + + /* Warn if the ieee802154 core thinks MLME frames can be sent while the + * net interface expects this cannot happen. + */ + if (WARN_ON_ONCE(!netif_running(sdata->dev))) + return -ENETDOWN; + + ieee802154_tx(local, skb); + return ieee802154_sync_queue(local); +} + +int ieee802154_mlme_tx(struct ieee802154_local *local, + struct ieee802154_sub_if_data *sdata, + struct sk_buff *skb) +{ + int ret; + + rtnl_lock(); + ret = ieee802154_mlme_tx_locked(local, sdata, skb); + rtnl_unlock(); + + return ret; +} + +void ieee802154_mlme_op_post(struct ieee802154_local *local) +{ + ieee802154_release_queue(local); +} + +int ieee802154_mlme_tx_one_locked(struct ieee802154_local *local, + struct ieee802154_sub_if_data *sdata, + struct sk_buff *skb) +{ + int ret; + + ieee802154_mlme_op_pre(local); + ret = ieee802154_mlme_tx_locked(local, sdata, skb); + ieee802154_mlme_op_post(local); + + return ret; +} + +static bool ieee802154_queue_is_stopped(struct ieee802154_local *local) +{ + return test_bit(WPAN_PHY_FLAG_STATE_QUEUE_STOPPED, &local->phy->flags); +} + +static netdev_tx_t +ieee802154_hot_tx(struct ieee802154_local *local, struct sk_buff *skb) +{ + /* Warn if the net interface tries to transmit frames while the + * ieee802154 core assumes the queue is stopped. + */ + WARN_ON_ONCE(ieee802154_queue_is_stopped(local)); + + return ieee802154_tx(local, skb); +} + +netdev_tx_t +ieee802154_monitor_start_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev); + + skb->skb_iif = dev->ifindex; + + return ieee802154_hot_tx(sdata->local, skb); +} + +netdev_tx_t +ieee802154_subif_start_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev); + int rc; + + /* TODO we should move it to wpan_dev_hard_header and dev_hard_header + * functions. The reason is wireshark will show a mac header which is + * with security fields but the payload is not encrypted. + */ + rc = mac802154_llsec_encrypt(&sdata->sec, skb); + if (rc) { + netdev_warn(dev, "encryption failed: %i\n", rc); + kfree_skb(skb); + return NETDEV_TX_OK; + } + + skb->skb_iif = dev->ifindex; + + return ieee802154_hot_tx(sdata->local, skb); +} -- cgit v1.3.1