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, 318 insertions, 0 deletions

diff --git a/net/mac80211/fils_aead.c b/net/mac80211/fils_aead.c
new file mode 100644
index 000000000..293590976
--- /dev/null
+++ b/net/mac80211/fils_aead.c
@@ -0,0 +1,318 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * FILS AEAD for (Re)Association Request/Response frames
+ * Copyright 2016, Qualcomm Atheros, Inc.
+ */
+
+#include <crypto/aes-cbc-macs.h>
+#include <crypto/skcipher.h>
+#include <crypto/utils.h>
+
+#include "ieee80211_i.h"
+#include "fils_aead.h"
+
+static void gf_mulx(u8 *pad)
+{
+	u64 a = get_unaligned_be64(pad);
+	u64 b = get_unaligned_be64(pad + 8);
+
+	put_unaligned_be64((a << 1) | (b >> 63), pad);
+	put_unaligned_be64((b << 1) ^ ((a >> 63) ? 0x87 : 0), pad + 8);
+}
+
+static int aes_s2v(const u8 *in_key, size_t key_len,
+		   size_t num_elem, const u8 *addr[], size_t len[], u8 *v)
+{
+	u8 d[AES_BLOCK_SIZE], tmp[AES_BLOCK_SIZE] = {};
+	struct aes_cmac_key key __cleanup(aes_cmac_zeroize_key);
+	struct aes_cmac_ctx ctx;
+	size_t i;
+	int res;
+
+	res = aes_cmac_preparekey(&key, in_key, key_len);
+	if (res)
+		return res;
+
+	/* D = AES-CMAC(K, <zero>) */
+	aes_cmac(&key, tmp, AES_BLOCK_SIZE, d);
+
+	for (i = 0; i < num_elem - 1; i++) {
+		/* D = dbl(D) xor AES_CMAC(K, Si) */
+		gf_mulx(d); /* dbl */
+		aes_cmac(&key, addr[i], len[i], tmp);
+		crypto_xor(d, tmp, AES_BLOCK_SIZE);
+	}
+
+	aes_cmac_init(&ctx, &key);
+
+	if (len[i] >= AES_BLOCK_SIZE) {
+		/* len(Sn) >= 128 */
+		/* T = Sn xorend D */
+		aes_cmac_update(&ctx, addr[i], len[i] - AES_BLOCK_SIZE);
+		crypto_xor(d, addr[i] + len[i] - AES_BLOCK_SIZE,
+			   AES_BLOCK_SIZE);
+	} else {
+		/* len(Sn) < 128 */
+		/* T = dbl(D) xor pad(Sn) */
+		gf_mulx(d); /* dbl */
+		crypto_xor(d, addr[i], len[i]);
+		d[len[i]] ^= 0x80;
+	}
+	/* V = AES-CMAC(K, T) */
+	aes_cmac_update(&ctx, d, AES_BLOCK_SIZE);
+	aes_cmac_final(&ctx, v);
+
+	return 0;
+}
+
+/* Note: addr[] and len[] needs to have one extra slot at the end. */
+static int aes_siv_encrypt(const u8 *key, size_t key_len,
+			   const u8 *plain, size_t plain_len,
+			   size_t num_elem, const u8 *addr[],
+			   size_t len[], u8 *out)
+{
+	u8 v[AES_BLOCK_SIZE];
+	struct crypto_skcipher *tfm2;
+	struct skcipher_request *req;
+	int res;
+	struct scatterlist src[1], dst[1];
+	u8 *tmp;
+
+	key_len /= 2; /* S2V key || CTR key */
+
+	addr[num_elem] = plain;
+	len[num_elem] = plain_len;
+	num_elem++;
+
+	/* S2V */
+	res = aes_s2v(key /* K1 */, key_len, num_elem, addr, len, v);
+	if (res)
+		return res;
+
+	/* Use a temporary buffer of the plaintext to handle need for
+	 * overwriting this during AES-CTR.
+	 */
+	tmp = kmemdup(plain, plain_len, GFP_KERNEL);
+	if (!tmp)
+		return -ENOMEM;
+
+	/* IV for CTR before encrypted data */
+	memcpy(out, v, AES_BLOCK_SIZE);
+
+	/* Synthetic IV to be used as the initial counter in CTR:
+	 * Q = V bitand (1^64 || 0^1 || 1^31 || 0^1 || 1^31)
+	 */
+	v[8] &= 0x7f;
+	v[12] &= 0x7f;
+
+	/* CTR */
+
+	tfm2 = crypto_alloc_skcipher("ctr(aes)", 0, CRYPTO_ALG_ASYNC);
+	if (IS_ERR(tfm2)) {
+		kfree(tmp);
+		return PTR_ERR(tfm2);
+	}
+	/* K2 for CTR */
+	res = crypto_skcipher_setkey(tfm2, key + key_len, key_len);
+	if (res)
+		goto fail;
+
+	req = skcipher_request_alloc(tfm2, GFP_KERNEL);
+	if (!req) {
+		res = -ENOMEM;
+		goto fail;
+	}
+
+	sg_init_one(src, tmp, plain_len);
+	sg_init_one(dst, out + AES_BLOCK_SIZE, plain_len);
+	skcipher_request_set_crypt(req, src, dst, plain_len, v);
+	res = crypto_skcipher_encrypt(req);
+	skcipher_request_free(req);
+fail:
+	kfree(tmp);
+	crypto_free_skcipher(tfm2);
+	return res;
+}
+
+/* Note: addr[] and len[] needs to have one extra slot at the end. */
+static int aes_siv_decrypt(const u8 *key, size_t key_len,
+			   const u8 *iv_crypt, size_t iv_c_len,
+			   size_t num_elem, const u8 *addr[], size_t len[],
+			   u8 *out)
+{
+	struct crypto_skcipher *tfm2;
+	struct skcipher_request *req;
+	struct scatterlist src[1], dst[1];
+	size_t crypt_len;
+	int res;
+	u8 frame_iv[AES_BLOCK_SIZE], iv[AES_BLOCK_SIZE];
+	u8 check[AES_BLOCK_SIZE];
+
+	crypt_len = iv_c_len - AES_BLOCK_SIZE;
+	key_len /= 2; /* S2V key || CTR key */
+	addr[num_elem] = out;
+	len[num_elem] = crypt_len;
+	num_elem++;
+
+	memcpy(iv, iv_crypt, AES_BLOCK_SIZE);
+	memcpy(frame_iv, iv_crypt, AES_BLOCK_SIZE);
+
+	/* Synthetic IV to be used as the initial counter in CTR:
+	 * Q = V bitand (1^64 || 0^1 || 1^31 || 0^1 || 1^31)
+	 */
+	iv[8] &= 0x7f;
+	iv[12] &= 0x7f;
+
+	/* CTR */
+
+	tfm2 = crypto_alloc_skcipher("ctr(aes)", 0, CRYPTO_ALG_ASYNC);
+	if (IS_ERR(tfm2))
+		return PTR_ERR(tfm2);
+	/* K2 for CTR */
+	res = crypto_skcipher_setkey(tfm2, key + key_len, key_len);
+	if (res) {
+		crypto_free_skcipher(tfm2);
+		return res;
+	}
+
+	req = skcipher_request_alloc(tfm2, GFP_KERNEL);
+	if (!req) {
+		crypto_free_skcipher(tfm2);
+		return -ENOMEM;
+	}
+
+	sg_init_one(src, iv_crypt + AES_BLOCK_SIZE, crypt_len);
+	sg_init_one(dst, out, crypt_len);
+	skcipher_request_set_crypt(req, src, dst, crypt_len, iv);
+	res = crypto_skcipher_decrypt(req);
+	skcipher_request_free(req);
+	crypto_free_skcipher(tfm2);
+	if (res)
+		return res;
+
+	/* S2V */
+	res = aes_s2v(key /* K1 */, key_len, num_elem, addr, len, check);
+	if (res)
+		return res;
+	if (memcmp(check, frame_iv, AES_BLOCK_SIZE) != 0)
+		return -EINVAL;
+	return 0;
+}
+
+int fils_encrypt_assoc_req(struct sk_buff *skb,
+			   struct ieee80211_mgd_assoc_data *assoc_data)
+{
+	struct ieee80211_mgmt *mgmt = (void *)skb->data;
+	u8 *capab, *ies, *encr;
+	const u8 *addr[5 + 1];
+	const struct element *session;
+	size_t len[5 + 1];
+	size_t crypt_len;
+
+	if (ieee80211_is_reassoc_req(mgmt->frame_control)) {
+		capab = (u8 *)&mgmt->u.reassoc_req.capab_info;
+		ies = mgmt->u.reassoc_req.variable;
+	} else {
+		capab = (u8 *)&mgmt->u.assoc_req.capab_info;
+		ies = mgmt->u.assoc_req.variable;
+	}
+
+	session = cfg80211_find_ext_elem(WLAN_EID_EXT_FILS_SESSION,
+					 ies, skb->data + skb->len - ies);
+	if (!session || session->datalen != 1 + 8)
+		return -EINVAL;
+	/* encrypt after FILS Session element */
+	encr = (u8 *)session->data + 1 + 8;
+
+	/* AES-SIV AAD vectors */
+
+	/* The STA's MAC address */
+	addr[0] = mgmt->sa;
+	len[0] = ETH_ALEN;
+	/* The AP's BSSID */
+	addr[1] = mgmt->da;
+	len[1] = ETH_ALEN;
+	/* The STA's nonce */
+	addr[2] = assoc_data->fils_nonces;
+	len[2] = FILS_NONCE_LEN;
+	/* The AP's nonce */
+	addr[3] = &assoc_data->fils_nonces[FILS_NONCE_LEN];
+	len[3] = FILS_NONCE_LEN;
+	/* The (Re)Association Request frame from the Capability Information
+	 * field to the FILS Session element (both inclusive).
+	 */
+	addr[4] = capab;
+	len[4] = encr - capab;
+
+	crypt_len = skb->data + skb->len - encr;
+	skb_put(skb, AES_BLOCK_SIZE);
+	return aes_siv_encrypt(assoc_data->fils_kek, assoc_data->fils_kek_len,
+			       encr, crypt_len, 5, addr, len, encr);
+}
+
+int fils_decrypt_assoc_resp(struct ieee80211_sub_if_data *sdata,
+			    u8 *frame, size_t *frame_len,
+			    struct ieee80211_mgd_assoc_data *assoc_data)
+{
+	struct ieee80211_mgmt *mgmt = (void *)frame;
+	u8 *capab, *ies, *encr;
+	const u8 *addr[5 + 1];
+	const struct element *session;
+	size_t len[5 + 1];
+	int res;
+	size_t crypt_len;
+
+	if (*frame_len < 24 + 6)
+		return -EINVAL;
+
+	capab = (u8 *)&mgmt->u.assoc_resp.capab_info;
+	ies = mgmt->u.assoc_resp.variable;
+	session = cfg80211_find_ext_elem(WLAN_EID_EXT_FILS_SESSION,
+					 ies, frame + *frame_len - ies);
+	if (!session || session->datalen != 1 + 8) {
+		mlme_dbg(sdata,
+			 "No (valid) FILS Session element in (Re)Association Response frame from %pM",
+			 mgmt->sa);
+		return -EINVAL;
+	}
+	/* decrypt after FILS Session element */
+	encr = (u8 *)session->data + 1 + 8;
+
+	/* AES-SIV AAD vectors */
+
+	/* The AP's BSSID */
+	addr[0] = mgmt->sa;
+	len[0] = ETH_ALEN;
+	/* The STA's MAC address */
+	addr[1] = mgmt->da;
+	len[1] = ETH_ALEN;
+	/* The AP's nonce */
+	addr[2] = &assoc_data->fils_nonces[FILS_NONCE_LEN];
+	len[2] = FILS_NONCE_LEN;
+	/* The STA's nonce */
+	addr[3] = assoc_data->fils_nonces;
+	len[3] = FILS_NONCE_LEN;
+	/* The (Re)Association Response frame from the Capability Information
+	 * field to the FILS Session element (both inclusive).
+	 */
+	addr[4] = capab;
+	len[4] = encr - capab;
+
+	crypt_len = frame + *frame_len - encr;
+	if (crypt_len < AES_BLOCK_SIZE) {
+		mlme_dbg(sdata,
+			 "Not enough room for AES-SIV data after FILS Session element in (Re)Association Response frame from %pM",
+			 mgmt->sa);
+		return -EINVAL;
+	}
+	res = aes_siv_decrypt(assoc_data->fils_kek, assoc_data->fils_kek_len,
+			      encr, crypt_len, 5, addr, len, encr);
+	if (res != 0) {
+		mlme_dbg(sdata,
+			 "AES-SIV decryption of (Re)Association Response frame from %pM failed",
+			 mgmt->sa);
+		return res;
+	}
+	*frame_len -= AES_BLOCK_SIZE;
+	return 0;
+}