ftrace: Synchronize the initialization of ftrace_opsgrafted

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 <rostedt@goodmis.org>

1 files changed, 338 insertions, 0 deletions

diff --git a/include/trace/events/net.h b/include/trace/events/net.h
new file mode 100644
index 000000000..dbc2c5598
--- /dev/null
+++ b/include/trace/events/net.h
@@ -0,0 +1,338 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM net
+
+#if !defined(_TRACE_NET_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_NET_H
+
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/if_vlan.h>
+#include <linux/ip.h>
+#include <linux/tracepoint.h>
+#include <net/busy_poll.h>
+
+TRACE_EVENT(net_dev_start_xmit,
+
+	TP_PROTO(const struct sk_buff *skb, const struct net_device *dev),
+
+	TP_ARGS(skb, dev),
+
+	TP_STRUCT__entry(
+		__string(	name,			dev->name	)
+		__field(	u16,			queue_mapping	)
+		__field(	const void *,		skbaddr		)
+		__field(	bool,			vlan_tagged	)
+		__field(	u16,			vlan_proto	)
+		__field(	u16,			vlan_tci	)
+		__field(	u16,			protocol	)
+		__field(	u8,			ip_summed	)
+		__field(	unsigned int,		len		)
+		__field(	unsigned int,		data_len	)
+		__field(	int,			network_offset	)
+		__field(	bool,			transport_offset_valid)
+		__field(	int,			transport_offset)
+		__field(	u8,			tx_flags	)
+		__field(	u16,			gso_size	)
+		__field(	u16,			gso_segs	)
+		__field(	u16,			gso_type	)
+		__field(	u64,			net_cookie	)
+	),
+
+	TP_fast_assign(
+		__assign_str(name);
+		__entry->queue_mapping = skb->queue_mapping;
+		__entry->skbaddr = skb;
+		__entry->vlan_tagged = skb_vlan_tag_present(skb);
+		__entry->vlan_proto = ntohs(skb->vlan_proto);
+		__entry->vlan_tci = skb_vlan_tag_get(skb);
+		__entry->protocol = ntohs(skb->protocol);
+		__entry->ip_summed = skb->ip_summed;
+		__entry->len = skb->len;
+		__entry->data_len = skb->data_len;
+		__entry->network_offset = skb_network_offset(skb);
+		__entry->transport_offset_valid =
+			skb_transport_header_was_set(skb);
+		__entry->transport_offset = skb_transport_header_was_set(skb) ?
+			skb_transport_offset(skb) : 0;
+		__entry->tx_flags = skb_shinfo(skb)->tx_flags;
+		__entry->gso_size = skb_shinfo(skb)->gso_size;
+		__entry->gso_segs = skb_shinfo(skb)->gso_segs;
+		__entry->gso_type = skb_shinfo(skb)->gso_type;
+		__entry->net_cookie = dev_net(dev)->net_cookie;
+	),
+
+	TP_printk("dev=%s queue_mapping=%u skbaddr=%p vlan_tagged=%d vlan_proto=0x%04x vlan_tci=0x%04x protocol=0x%04x ip_summed=%d len=%u data_len=%u network_offset=%d transport_offset_valid=%d transport_offset=%d tx_flags=%d gso_size=%d gso_segs=%d gso_type=%#x net_cookie=%llu",
+		  __get_str(name), __entry->queue_mapping, __entry->skbaddr,
+		  __entry->vlan_tagged, __entry->vlan_proto, __entry->vlan_tci,
+		  __entry->protocol, __entry->ip_summed, __entry->len,
+		  __entry->data_len,
+		  __entry->network_offset, __entry->transport_offset_valid,
+		  __entry->transport_offset, __entry->tx_flags,
+		  __entry->gso_size, __entry->gso_segs,
+		  __entry->gso_type, __entry->net_cookie)
+);
+
+TRACE_EVENT(net_dev_xmit,
+
+	TP_PROTO(struct sk_buff *skb,
+		 int rc,
+		 struct net_device *dev,
+		 unsigned int skb_len),
+
+	TP_ARGS(skb, rc, dev, skb_len),
+
+	TP_STRUCT__entry(
+		__field(	void *,		skbaddr		)
+		__field(	unsigned int,	len		)
+		__field(	int,		rc		)
+		__string(	name,		dev->name	)
+		__field(	u64,		net_cookie	)
+	),
+
+	TP_fast_assign(
+		__entry->skbaddr = skb;
+		__entry->len = skb_len;
+		__entry->rc = rc;
+		__entry->net_cookie = dev_net(dev)->net_cookie;
+		__assign_str(name);
+	),
+
+	TP_printk("dev=%s skbaddr=%p len=%u rc=%d net_cookie=%llu",
+		__get_str(name), __entry->skbaddr,
+		__entry->len, __entry->rc,
+		__entry->net_cookie)
+);
+
+TRACE_EVENT(net_dev_xmit_timeout,
+
+	TP_PROTO(struct net_device *dev,
+		 int queue_index),
+
+	TP_ARGS(dev, queue_index),
+
+	TP_STRUCT__entry(
+		__string(	name,		dev->name	)
+		__string(	driver,		netdev_drivername(dev))
+		__field(	int,		queue_index	)
+		__field(	u64,		net_cookie	)
+	),
+
+	TP_fast_assign(
+		__assign_str(name);
+		__assign_str(driver);
+		__entry->queue_index = queue_index;
+		__entry->net_cookie = dev_net(dev)->net_cookie;
+	),
+
+	TP_printk("dev=%s driver=%s queue=%d net_cookie=%llu",
+		__get_str(name), __get_str(driver),
+		__entry->queue_index, __entry->net_cookie)
+);
+
+DECLARE_EVENT_CLASS(net_dev_template,
+
+	TP_PROTO(struct sk_buff *skb),
+
+	TP_ARGS(skb),
+
+	TP_STRUCT__entry(
+		__field(	void *,		skbaddr		)
+		__field(	unsigned int,	len		)
+		__string(	name,		skb->dev->name	)
+		__field(	u64,		net_cookie	)
+	),
+
+	TP_fast_assign(
+		__entry->skbaddr = skb;
+		__entry->len = skb->len;
+		__entry->net_cookie = dev_net(skb->dev)->net_cookie;
+		__assign_str(name);
+	),
+
+	TP_printk("dev=%s skbaddr=%p len=%u net_cookie=%llu",
+		__get_str(name), __entry->skbaddr,
+		__entry->len,
+		__entry->net_cookie)
+)
+
+DEFINE_EVENT(net_dev_template, net_dev_queue,
+
+	TP_PROTO(struct sk_buff *skb),
+
+	TP_ARGS(skb)
+);
+
+DEFINE_EVENT(net_dev_template, netif_receive_skb,
+
+	TP_PROTO(struct sk_buff *skb),
+
+	TP_ARGS(skb)
+);
+
+DEFINE_EVENT(net_dev_template, netif_rx,
+
+	TP_PROTO(struct sk_buff *skb),
+
+	TP_ARGS(skb)
+);
+
+DECLARE_EVENT_CLASS(net_dev_rx_verbose_template,
+
+	TP_PROTO(const struct sk_buff *skb),
+
+	TP_ARGS(skb),
+
+	TP_STRUCT__entry(
+		__string(	name,			skb->dev->name	)
+		__field(	unsigned int,		napi_id		)
+		__field(	u16,			queue_mapping	)
+		__field(	const void *,		skbaddr		)
+		__field(	bool,			vlan_tagged	)
+		__field(	u16,			vlan_proto	)
+		__field(	u16,			vlan_tci	)
+		__field(	u16,			protocol	)
+		__field(	u8,			ip_summed	)
+		__field(	u32,			hash		)
+		__field(	bool,			l4_hash		)
+		__field(	unsigned int,		len		)
+		__field(	unsigned int,		data_len	)
+		__field(	unsigned int,		truesize	)
+		__field(	bool,			mac_header_valid)
+		__field(	int,			mac_header	)
+		__field(	unsigned char,		nr_frags	)
+		__field(	u16,			gso_size	)
+		__field(	u16,			gso_type	)
+		__field(	u64,			net_cookie	)
+	),
+
+	TP_fast_assign(
+		__assign_str(name);
+#ifdef CONFIG_NET_RX_BUSY_POLL
+		__entry->napi_id = napi_id_valid(skb->napi_id) ?
+				   skb->napi_id : 0;
+#else
+		__entry->napi_id = 0;
+#endif
+		__entry->queue_mapping = skb->queue_mapping;
+		__entry->skbaddr = skb;
+		__entry->vlan_tagged = skb_vlan_tag_present(skb);
+		__entry->vlan_proto = ntohs(skb->vlan_proto);
+		__entry->vlan_tci = skb_vlan_tag_get(skb);
+		__entry->protocol = ntohs(skb->protocol);
+		__entry->ip_summed = skb->ip_summed;
+		__entry->hash = skb->hash;
+		__entry->l4_hash = skb->l4_hash;
+		__entry->len = skb->len;
+		__entry->data_len = skb->data_len;
+		__entry->truesize = skb->truesize;
+		__entry->mac_header_valid = skb_mac_header_was_set(skb);
+		__entry->mac_header = skb_mac_header(skb) - skb->data;
+		__entry->nr_frags = skb_shinfo(skb)->nr_frags;
+		__entry->gso_size = skb_shinfo(skb)->gso_size;
+		__entry->gso_type = skb_shinfo(skb)->gso_type;
+		__entry->net_cookie = dev_net(skb->dev)->net_cookie;
+	),
+
+	TP_printk("dev=%s napi_id=%#x queue_mapping=%u skbaddr=%p vlan_tagged=%d vlan_proto=0x%04x vlan_tci=0x%04x protocol=0x%04x ip_summed=%d hash=0x%08x l4_hash=%d len=%u data_len=%u truesize=%u mac_header_valid=%d mac_header=%d nr_frags=%d gso_size=%d gso_type=%#x net_cookie=%llu",
+		  __get_str(name), __entry->napi_id, __entry->queue_mapping,
+		  __entry->skbaddr, __entry->vlan_tagged, __entry->vlan_proto,
+		  __entry->vlan_tci, __entry->protocol, __entry->ip_summed,
+		  __entry->hash, __entry->l4_hash, __entry->len,
+		  __entry->data_len, __entry->truesize,
+		  __entry->mac_header_valid, __entry->mac_header,
+		  __entry->nr_frags, __entry->gso_size,
+		  __entry->gso_type, __entry->net_cookie)
+);
+
+DEFINE_EVENT(net_dev_rx_verbose_template, napi_gro_frags_entry,
+
+	TP_PROTO(const struct sk_buff *skb),
+
+	TP_ARGS(skb)
+);
+
+DEFINE_EVENT(net_dev_rx_verbose_template, napi_gro_receive_entry,
+
+	TP_PROTO(const struct sk_buff *skb),
+
+	TP_ARGS(skb)
+);
+
+DEFINE_EVENT(net_dev_rx_verbose_template, netif_receive_skb_entry,
+
+	TP_PROTO(const struct sk_buff *skb),
+
+	TP_ARGS(skb)
+);
+
+DEFINE_EVENT(net_dev_rx_verbose_template, netif_receive_skb_list_entry,
+
+	TP_PROTO(const struct sk_buff *skb),
+
+	TP_ARGS(skb)
+);
+
+DEFINE_EVENT(net_dev_rx_verbose_template, netif_rx_entry,
+
+	TP_PROTO(const struct sk_buff *skb),
+
+	TP_ARGS(skb)
+);
+
+DECLARE_EVENT_CLASS(net_dev_rx_exit_template,
+
+	TP_PROTO(int ret),
+
+	TP_ARGS(ret),
+
+	TP_STRUCT__entry(
+		__field(int,	ret)
+	),
+
+	TP_fast_assign(
+		__entry->ret = ret;
+	),
+
+	TP_printk("ret=%d", __entry->ret)
+);
+
+DEFINE_EVENT(net_dev_rx_exit_template, napi_gro_frags_exit,
+
+	TP_PROTO(int ret),
+
+	TP_ARGS(ret)
+);
+
+DEFINE_EVENT(net_dev_rx_exit_template, napi_gro_receive_exit,
+
+	TP_PROTO(int ret),
+
+	TP_ARGS(ret)
+);
+
+DEFINE_EVENT(net_dev_rx_exit_template, netif_receive_skb_exit,
+
+	TP_PROTO(int ret),
+
+	TP_ARGS(ret)
+);
+
+DEFINE_EVENT(net_dev_rx_exit_template, netif_rx_exit,
+
+	TP_PROTO(int ret),
+
+	TP_ARGS(ret)
+);
+
+DEFINE_EVENT(net_dev_rx_exit_template, netif_receive_skb_list_exit,
+
+	TP_PROTO(int ret),
+
+	TP_ARGS(ret)
+);
+
+#endif /* _TRACE_NET_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>