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, 187 insertions, 0 deletions

diff --git a/include/trace/events/bridge.h b/include/trace/events/bridge.h
new file mode 100644
index 000000000..3fe4725c8
--- /dev/null
+++ b/include/trace/events/bridge.h
@@ -0,0 +1,187 @@
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM bridge
+
+#if !defined(_TRACE_BRIDGE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_BRIDGE_H
+
+#include <linux/netdevice.h>
+#include <linux/tracepoint.h>
+
+#include "../../../net/bridge/br_private.h"
+
+TRACE_EVENT(br_fdb_add,
+
+	TP_PROTO(struct ndmsg *ndm, struct net_device *dev,
+		 const unsigned char *addr, u16 vid, u16 nlh_flags),
+
+	TP_ARGS(ndm, dev, addr, vid, nlh_flags),
+
+	TP_STRUCT__entry(
+		__field(u8, ndm_flags)
+		__string(dev, dev->name)
+		__array(unsigned char, addr, ETH_ALEN)
+		__field(u16, vid)
+		__field(u16, nlh_flags)
+	),
+
+	TP_fast_assign(
+		__assign_str(dev);
+		memcpy(__entry->addr, addr, ETH_ALEN);
+		__entry->vid = vid;
+		__entry->nlh_flags = nlh_flags;
+		__entry->ndm_flags = ndm->ndm_flags;
+	),
+
+	TP_printk("dev %s addr %02x:%02x:%02x:%02x:%02x:%02x vid %u nlh_flags %04x ndm_flags %02x",
+		  __get_str(dev), __entry->addr[0], __entry->addr[1],
+		  __entry->addr[2], __entry->addr[3], __entry->addr[4],
+		  __entry->addr[5], __entry->vid,
+		  __entry->nlh_flags, __entry->ndm_flags)
+);
+
+TRACE_EVENT(br_fdb_external_learn_add,
+
+	TP_PROTO(struct net_bridge *br, struct net_bridge_port *p,
+		 const unsigned char *addr, u16 vid),
+
+	TP_ARGS(br, p, addr, vid),
+
+	TP_STRUCT__entry(
+		__string(br_dev, br->dev->name)
+		__string(dev, p ? p->dev->name : "null")
+		__array(unsigned char, addr, ETH_ALEN)
+		__field(u16, vid)
+	),
+
+	TP_fast_assign(
+		__assign_str(br_dev);
+		__assign_str(dev);
+		memcpy(__entry->addr, addr, ETH_ALEN);
+		__entry->vid = vid;
+	),
+
+	TP_printk("br_dev %s port %s addr %02x:%02x:%02x:%02x:%02x:%02x vid %u",
+		  __get_str(br_dev), __get_str(dev), __entry->addr[0],
+		  __entry->addr[1], __entry->addr[2], __entry->addr[3],
+		  __entry->addr[4], __entry->addr[5], __entry->vid)
+);
+
+TRACE_EVENT(fdb_delete,
+
+	TP_PROTO(struct net_bridge *br, struct net_bridge_fdb_entry *f),
+
+	TP_ARGS(br, f),
+
+	TP_STRUCT__entry(
+		__string(br_dev, br->dev->name)
+		__string(dev, f->dst ? f->dst->dev->name : "null")
+		__array(unsigned char, addr, ETH_ALEN)
+		__field(u16, vid)
+	),
+
+	TP_fast_assign(
+		__assign_str(br_dev);
+		__assign_str(dev);
+		memcpy(__entry->addr, f->key.addr.addr, ETH_ALEN);
+		__entry->vid = f->key.vlan_id;
+	),
+
+	TP_printk("br_dev %s dev %s addr %02x:%02x:%02x:%02x:%02x:%02x vid %u",
+		  __get_str(br_dev), __get_str(dev), __entry->addr[0],
+		  __entry->addr[1], __entry->addr[2], __entry->addr[3],
+		  __entry->addr[4], __entry->addr[5], __entry->vid)
+);
+
+TRACE_EVENT(br_fdb_update,
+
+	TP_PROTO(struct net_bridge *br, struct net_bridge_port *source,
+		 const unsigned char *addr, u16 vid, unsigned long flags),
+
+	TP_ARGS(br, source, addr, vid, flags),
+
+	TP_STRUCT__entry(
+		__string(br_dev, br->dev->name)
+		__string(dev, source->dev->name)
+		__array(unsigned char, addr, ETH_ALEN)
+		__field(u16, vid)
+		__field(unsigned long, flags)
+	),
+
+	TP_fast_assign(
+		__assign_str(br_dev);
+		__assign_str(dev);
+		memcpy(__entry->addr, addr, ETH_ALEN);
+		__entry->vid = vid;
+		__entry->flags = flags;
+	),
+
+	TP_printk("br_dev %s source %s addr %02x:%02x:%02x:%02x:%02x:%02x vid %u flags 0x%lx",
+		  __get_str(br_dev), __get_str(dev), __entry->addr[0],
+		  __entry->addr[1], __entry->addr[2], __entry->addr[3],
+		  __entry->addr[4], __entry->addr[5], __entry->vid,
+		  __entry->flags)
+);
+
+TRACE_EVENT(br_mdb_full,
+
+	TP_PROTO(const struct net_device *dev,
+		 const struct br_ip *group),
+
+	TP_ARGS(dev, group),
+
+	TP_STRUCT__entry(
+		__string(dev, dev->name)
+		__field(int, af)
+		__field(u16, vid)
+		__array(__u8, src, 16)
+		__array(__u8, grp, 16)
+		__array(__u8, grpmac, ETH_ALEN) /* For af == 0. */
+	),
+
+	TP_fast_assign(
+		struct in6_addr *in6;
+
+		__assign_str(dev);
+		__entry->vid = group->vid;
+
+		if (!group->proto) {
+			__entry->af = 0;
+
+			memset(__entry->src, 0, sizeof(__entry->src));
+			memset(__entry->grp, 0, sizeof(__entry->grp));
+			memcpy(__entry->grpmac, group->dst.mac_addr, ETH_ALEN);
+		} else if (group->proto == htons(ETH_P_IP)) {
+			__entry->af = AF_INET;
+
+			in6 = (struct in6_addr *)__entry->src;
+			ipv6_addr_set_v4mapped(group->src.ip4, in6);
+
+			in6 = (struct in6_addr *)__entry->grp;
+			ipv6_addr_set_v4mapped(group->dst.ip4, in6);
+
+			memset(__entry->grpmac, 0, ETH_ALEN);
+
+#if IS_ENABLED(CONFIG_IPV6)
+		} else {
+			__entry->af = AF_INET6;
+
+			in6 = (struct in6_addr *)__entry->src;
+			*in6 = group->src.ip6;
+
+			in6 = (struct in6_addr *)__entry->grp;
+			*in6 = group->dst.ip6;
+
+			memset(__entry->grpmac, 0, ETH_ALEN);
+#endif
+		}
+	),
+
+	TP_printk("dev %s af %u src %pI6c grp %pI6c/%pM vid %u",
+		  __get_str(dev), __entry->af, __entry->src, __entry->grp,
+		  __entry->grpmac, __entry->vid)
+);
+
+#endif /* _TRACE_BRIDGE_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>