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, 381 insertions, 0 deletions

diff --git a/net/ieee802154/header_ops.c b/net/ieee802154/header_ops.c
new file mode 100644
index 000000000..a9f0c8df5
--- /dev/null
+++ b/net/ieee802154/header_ops.c
@@ -0,0 +1,381 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2014 Fraunhofer ITWM
+ *
+ * Written by:
+ * Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
+ */
+
+#include <linux/ieee802154.h>
+
+#include <net/mac802154.h>
+#include <net/ieee802154_netdev.h>
+
+static int
+ieee802154_hdr_push_addr(u8 *buf, const struct ieee802154_addr *addr,
+			 bool omit_pan)
+{
+	int pos = 0;
+
+	if (addr->mode == IEEE802154_ADDR_NONE)
+		return 0;
+
+	if (!omit_pan) {
+		memcpy(buf + pos, &addr->pan_id, 2);
+		pos += 2;
+	}
+
+	switch (addr->mode) {
+	case IEEE802154_ADDR_SHORT:
+		memcpy(buf + pos, &addr->short_addr, 2);
+		pos += 2;
+		break;
+
+	case IEEE802154_ADDR_LONG:
+		memcpy(buf + pos, &addr->extended_addr, IEEE802154_ADDR_LEN);
+		pos += IEEE802154_ADDR_LEN;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	return pos;
+}
+
+static int
+ieee802154_hdr_push_sechdr(u8 *buf, const struct ieee802154_sechdr *hdr)
+{
+	int pos = 5;
+
+	memcpy(buf, hdr, 1);
+	memcpy(buf + 1, &hdr->frame_counter, 4);
+
+	switch (hdr->key_id_mode) {
+	case IEEE802154_SCF_KEY_IMPLICIT:
+		return pos;
+
+	case IEEE802154_SCF_KEY_INDEX:
+		break;
+
+	case IEEE802154_SCF_KEY_SHORT_INDEX:
+		memcpy(buf + pos, &hdr->short_src, 4);
+		pos += 4;
+		break;
+
+	case IEEE802154_SCF_KEY_HW_INDEX:
+		memcpy(buf + pos, &hdr->extended_src, IEEE802154_ADDR_LEN);
+		pos += IEEE802154_ADDR_LEN;
+		break;
+	}
+
+	buf[pos++] = hdr->key_id;
+
+	return pos;
+}
+
+int
+ieee802154_hdr_push(struct sk_buff *skb, struct ieee802154_hdr *hdr)
+{
+	u8 buf[IEEE802154_MAX_HEADER_LEN];
+	int pos = 2;
+	int rc;
+	struct ieee802154_hdr_fc *fc = &hdr->fc;
+
+	buf[pos++] = hdr->seq;
+
+	fc->dest_addr_mode = hdr->dest.mode;
+
+	rc = ieee802154_hdr_push_addr(buf + pos, &hdr->dest, false);
+	if (rc < 0)
+		return -EINVAL;
+	pos += rc;
+
+	fc->source_addr_mode = hdr->source.mode;
+
+	if (hdr->source.pan_id == hdr->dest.pan_id &&
+	    hdr->dest.mode != IEEE802154_ADDR_NONE)
+		fc->intra_pan = true;
+
+	rc = ieee802154_hdr_push_addr(buf + pos, &hdr->source, fc->intra_pan);
+	if (rc < 0)
+		return -EINVAL;
+	pos += rc;
+
+	if (fc->security_enabled) {
+		fc->version = 1;
+
+		rc = ieee802154_hdr_push_sechdr(buf + pos, &hdr->sec);
+		if (rc < 0)
+			return -EINVAL;
+
+		pos += rc;
+	}
+
+	memcpy(buf, fc, 2);
+
+	memcpy(skb_push(skb, pos), buf, pos);
+
+	return pos;
+}
+EXPORT_SYMBOL_GPL(ieee802154_hdr_push);
+
+int ieee802154_mac_cmd_push(struct sk_buff *skb, void *f,
+			    const void *pl, unsigned int pl_len)
+{
+	struct ieee802154_mac_cmd_frame *frame = f;
+	struct ieee802154_mac_cmd_pl *mac_pl = &frame->mac_pl;
+	struct ieee802154_hdr *mhr = &frame->mhr;
+	int ret;
+
+	skb_reserve(skb, sizeof(*mhr));
+	ret = ieee802154_hdr_push(skb, mhr);
+	if (ret < 0)
+		return ret;
+
+	skb_reset_mac_header(skb);
+	skb->mac_len = ret;
+
+	skb_put_data(skb, mac_pl, sizeof(*mac_pl));
+	skb_put_data(skb, pl, pl_len);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ieee802154_mac_cmd_push);
+
+int ieee802154_beacon_push(struct sk_buff *skb,
+			   struct ieee802154_beacon_frame *beacon)
+{
+	struct ieee802154_beacon_hdr *mac_pl = &beacon->mac_pl;
+	struct ieee802154_hdr *mhr = &beacon->mhr;
+	int ret;
+
+	skb_reserve(skb, sizeof(*mhr));
+	ret = ieee802154_hdr_push(skb, mhr);
+	if (ret < 0)
+		return ret;
+
+	skb_reset_mac_header(skb);
+	skb->mac_len = ret;
+
+	skb_put_data(skb, mac_pl, sizeof(*mac_pl));
+
+	if (mac_pl->pend_short_addr_count || mac_pl->pend_ext_addr_count)
+		return -EOPNOTSUPP;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ieee802154_beacon_push);
+
+static int
+ieee802154_hdr_get_addr(const u8 *buf, int mode, bool omit_pan,
+			struct ieee802154_addr *addr)
+{
+	int pos = 0;
+
+	if (mode == IEEE802154_ADDR_NONE) {
+		memset(addr, 0, sizeof(*addr));
+		addr->mode = IEEE802154_ADDR_NONE;
+		return 0;
+	}
+
+	addr->mode = mode;
+
+	if (!omit_pan) {
+		memcpy(&addr->pan_id, buf + pos, 2);
+		pos += 2;
+	}
+
+	if (mode == IEEE802154_ADDR_SHORT) {
+		memcpy(&addr->short_addr, buf + pos, 2);
+		return pos + 2;
+	} else {
+		memcpy(&addr->extended_addr, buf + pos, IEEE802154_ADDR_LEN);
+		return pos + IEEE802154_ADDR_LEN;
+	}
+}
+
+static int ieee802154_hdr_addr_len(int mode, bool omit_pan)
+{
+	int pan_len = omit_pan ? 0 : 2;
+
+	switch (mode) {
+	case IEEE802154_ADDR_NONE: return 0;
+	case IEEE802154_ADDR_SHORT: return 2 + pan_len;
+	case IEEE802154_ADDR_LONG: return IEEE802154_ADDR_LEN + pan_len;
+	default: return -EINVAL;
+	}
+}
+
+static int
+ieee802154_hdr_get_sechdr(const u8 *buf, struct ieee802154_sechdr *hdr)
+{
+	int pos = 5;
+
+	memcpy(hdr, buf, 1);
+	memcpy(&hdr->frame_counter, buf + 1, 4);
+
+	switch (hdr->key_id_mode) {
+	case IEEE802154_SCF_KEY_IMPLICIT:
+		return pos;
+
+	case IEEE802154_SCF_KEY_INDEX:
+		break;
+
+	case IEEE802154_SCF_KEY_SHORT_INDEX:
+		memcpy(&hdr->short_src, buf + pos, 4);
+		pos += 4;
+		break;
+
+	case IEEE802154_SCF_KEY_HW_INDEX:
+		memcpy(&hdr->extended_src, buf + pos, IEEE802154_ADDR_LEN);
+		pos += IEEE802154_ADDR_LEN;
+		break;
+	}
+
+	hdr->key_id = buf[pos++];
+
+	return pos;
+}
+
+static int ieee802154_sechdr_lengths[4] = {
+	[IEEE802154_SCF_KEY_IMPLICIT] = 5,
+	[IEEE802154_SCF_KEY_INDEX] = 6,
+	[IEEE802154_SCF_KEY_SHORT_INDEX] = 10,
+	[IEEE802154_SCF_KEY_HW_INDEX] = 14,
+};
+
+static int ieee802154_hdr_sechdr_len(u8 sc)
+{
+	return ieee802154_sechdr_lengths[IEEE802154_SCF_KEY_ID_MODE(sc)];
+}
+
+static int ieee802154_hdr_minlen(const struct ieee802154_hdr *hdr)
+{
+	int dlen, slen;
+
+	dlen = ieee802154_hdr_addr_len(hdr->fc.dest_addr_mode, false);
+	slen = ieee802154_hdr_addr_len(hdr->fc.source_addr_mode,
+				       hdr->fc.intra_pan);
+
+	if (slen < 0 || dlen < 0)
+		return -EINVAL;
+
+	return 3 + dlen + slen + hdr->fc.security_enabled;
+}
+
+static int
+ieee802154_hdr_get_addrs(const u8 *buf, struct ieee802154_hdr *hdr)
+{
+	int pos = 0;
+
+	pos += ieee802154_hdr_get_addr(buf + pos, hdr->fc.dest_addr_mode,
+				       false, &hdr->dest);
+	pos += ieee802154_hdr_get_addr(buf + pos, hdr->fc.source_addr_mode,
+				       hdr->fc.intra_pan, &hdr->source);
+
+	if (hdr->fc.intra_pan)
+		hdr->source.pan_id = hdr->dest.pan_id;
+
+	return pos;
+}
+
+int
+ieee802154_hdr_pull(struct sk_buff *skb, struct ieee802154_hdr *hdr)
+{
+	int pos = 3, rc;
+
+	if (!pskb_may_pull(skb, 3))
+		return -EINVAL;
+
+	memcpy(hdr, skb->data, 3);
+
+	rc = ieee802154_hdr_minlen(hdr);
+	if (rc < 0 || !pskb_may_pull(skb, rc))
+		return -EINVAL;
+
+	pos += ieee802154_hdr_get_addrs(skb->data + pos, hdr);
+
+	if (hdr->fc.security_enabled) {
+		int want = pos + ieee802154_hdr_sechdr_len(skb->data[pos]);
+
+		if (!pskb_may_pull(skb, want))
+			return -EINVAL;
+
+		pos += ieee802154_hdr_get_sechdr(skb->data + pos, &hdr->sec);
+	}
+
+	skb_pull(skb, pos);
+	return pos;
+}
+EXPORT_SYMBOL_GPL(ieee802154_hdr_pull);
+
+int ieee802154_mac_cmd_pl_pull(struct sk_buff *skb,
+			       struct ieee802154_mac_cmd_pl *mac_pl)
+{
+	if (!pskb_may_pull(skb, sizeof(*mac_pl)))
+		return -EINVAL;
+
+	memcpy(mac_pl, skb->data, sizeof(*mac_pl));
+	skb_pull(skb, sizeof(*mac_pl));
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ieee802154_mac_cmd_pl_pull);
+
+int
+ieee802154_hdr_peek_addrs(const struct sk_buff *skb, struct ieee802154_hdr *hdr)
+{
+	const u8 *buf = skb_mac_header(skb);
+	int pos = 3, rc;
+
+	if (buf + 3 > skb_tail_pointer(skb))
+		return -EINVAL;
+
+	memcpy(hdr, buf, 3);
+
+	rc = ieee802154_hdr_minlen(hdr);
+	if (rc < 0 || buf + rc > skb_tail_pointer(skb))
+		return -EINVAL;
+
+	pos += ieee802154_hdr_get_addrs(buf + pos, hdr);
+	return pos;
+}
+EXPORT_SYMBOL_GPL(ieee802154_hdr_peek_addrs);
+
+int
+ieee802154_hdr_peek(const struct sk_buff *skb, struct ieee802154_hdr *hdr)
+{
+	const u8 *buf = skb_mac_header(skb);
+	int pos;
+
+	pos = ieee802154_hdr_peek_addrs(skb, hdr);
+	if (pos < 0)
+		return -EINVAL;
+
+	if (hdr->fc.security_enabled) {
+		u8 key_id_mode = IEEE802154_SCF_KEY_ID_MODE(*(buf + pos));
+		int want = pos + ieee802154_sechdr_lengths[key_id_mode];
+
+		if (buf + want > skb_tail_pointer(skb))
+			return -EINVAL;
+
+		pos += ieee802154_hdr_get_sechdr(buf + pos, &hdr->sec);
+	}
+
+	return pos;
+}
+EXPORT_SYMBOL_GPL(ieee802154_hdr_peek);
+
+int ieee802154_max_payload(const struct ieee802154_hdr *hdr)
+{
+	int hlen = ieee802154_hdr_minlen(hdr);
+
+	if (hdr->fc.security_enabled) {
+		hlen += ieee802154_sechdr_lengths[hdr->sec.key_id_mode] - 1;
+		hlen += ieee802154_sechdr_authtag_len(&hdr->sec);
+	}
+
+	return IEEE802154_MTU - hlen - IEEE802154_MFR_SIZE;
+}
+EXPORT_SYMBOL_GPL(ieee802154_max_payload);