FAILED: patch "[PATCH] tls: rx: restore msg_iter before TLS 1.3 optimistic retry" failed to apply to 6.12-stable tree

FAILED: patch "[PATCH] tls: rx: restore msg_iter before TLS 1.3 optimistic retry" failed to apply to 6.12-stable tree

[gregkh]

The patch below does not apply to the 6.12-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x 1c8629651cb54f7b51db8fc0b1a9944e4a4b0f5e
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026081717-verbalize-stylist-2627@gregkh' --subject-prefix 'PATCH 6.12.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 1c8629651cb54f7b51db8fc0b1a9944e4a4b0f5e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=A9r=C3=A9my=20Jean?= <Jeremy.Jean@oss.cyber.gouv.fr>
Date: Tue, 4 Aug 2026 12:55:28 +0000
Subject: [PATCH] tls: rx: restore msg_iter before TLS 1.3 optimistic retry
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

tls_decrypt_sg() advances msg->msg_iter when it maps user pages for
the optimistic TLS 1.3 zero-copy path. If the decrypted record turns
out not to be unpadded application data, tls_decrypt_sw() retries into
a kernel skb, but leaves the iterator advanced.

The subsequent copy from the skb then writes decrypted bytes again at
a later point in the caller iovecs while recvmsg() reports only the
post-retry length. A TLS peer can trigger this after the receiver
enables TLS_RX_EXPECT_NO_PAD.

Revert the iterator by the number of bytes consumed by the optimistic
mapping before retrying without zero-copy.

Add a selftest which sends a TLS 1.3 control record with
TLS_RX_EXPECT_NO_PAD enabled and verifies that recvmsg() does not
overwrite later iovecs beyond the returned length.

Fixes: ce61327ce989 ("tls: rx: support optimistic decrypt to user buffer with TLS 1.3")
Cc: stable@vger.kernel.org
Signed-off-by: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr>
Link: https://patch.msgid.link/20260804125528.2139928-1-Jeremy.Jean@oss.cyber.gouv.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
index d2e399be8ef6..133ed7c89402 100644
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -1456,6 +1456,8 @@ tls_decrypt_sw(struct sock *sk, struct tls_context *tls_ctx,
 	/* If opportunistic TLS 1.3 ZC failed retry without ZC */
 	if (unlikely(darg->zc && prot->version == TLS_1_3_VERSION &&
 		     darg->tail != TLS_RECORD_TYPE_DATA)) {
+		iov_iter_revert(&msg->msg_iter, strp_msg(darg->skb)->full_len -
+				prot->overhead_size);
 		darg->zc = false;
 		if (!darg->tail)
 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXNOPADVIOL);
diff --git a/tools/testing/selftests/net/tls.c b/tools/testing/selftests/net/tls.c
index 3d6f553eaf97..a0e72e402748 100644
--- a/tools/testing/selftests/net/tls.c
+++ b/tools/testing/selftests/net/tls.c
@@ -1839,6 +1839,63 @@ TEST_F(tls, recv_efault)
 }
 
 #define TLS_RECORD_TYPE_HANDSHAKE      0x16
+
+TEST_F(tls_basic, recvmsg_nopad_retry_iov)
+{
+	char payload[32];
+	char first_iov[sizeof(payload)];
+	char later_iov[sizeof(payload) * 2];
+	char expected_later_iov[sizeof(later_iov)];
+	char cbuf[CMSG_SPACE(sizeof(char))];
+	struct tls_crypto_info_keys tls13;
+	struct iovec iov[] = {
+		{ .iov_base = first_iov, .iov_len = sizeof(first_iov) },
+		{ .iov_base = later_iov, .iov_len = sizeof(later_iov) },
+	};
+	struct msghdr msg = {
+		.msg_iov = iov,
+		.msg_iovlen = ARRAY_SIZE(iov),
+		.msg_control = cbuf,
+		.msg_controllen = sizeof(cbuf),
+	};
+	int one = 1;
+	int ret;
+	int i;
+
+	if (self->notls)
+		SKIP(return, "no TLS support");
+
+	tls_crypto_info_init(TLS_1_3_VERSION, TLS_CIPHER_AES_GCM_128,
+			     &tls13, 0);
+
+	ret = setsockopt(self->fd, SOL_TLS, TLS_TX, &tls13, tls13.len);
+	ASSERT_EQ(ret, 0);
+
+	ret = setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls13, tls13.len);
+	ASSERT_EQ(ret, 0);
+
+	ret = setsockopt(self->cfd, SOL_TLS, TLS_RX_EXPECT_NO_PAD,
+			 &one, sizeof(one));
+	ASSERT_EQ(ret, 0);
+
+	for (i = 0; i < sizeof(payload); i++)
+		payload[i] = 0x40 + i;
+	memset(first_iov, 0xa5, sizeof(first_iov));
+	memset(later_iov, 0x5a, sizeof(later_iov));
+	memset(expected_later_iov, 0x5a, sizeof(expected_later_iov));
+
+	/* A control record forces optimistic TLS 1.3 RX to retry. */
+	ret = tls_send_cmsg(self->fd, TLS_RECORD_TYPE_HANDSHAKE,
+			    payload, sizeof(payload), 0);
+	ASSERT_EQ(ret, sizeof(payload));
+
+	ret = recvmsg(self->cfd, &msg, 0);
+	ASSERT_EQ(ret, sizeof(payload));
+	EXPECT_EQ(memcmp(first_iov, payload, sizeof(payload)), 0);
+	EXPECT_EQ(memcmp(later_iov, expected_later_iov,
+			 sizeof(later_iov)), 0);
+}
+
 /* key_update, length 1, update_not_requested */
 static const char key_update_msg[] = "\x18\x00\x00\x01\x00";
 static void tls_send_keyupdate(struct __test_metadata *_metadata, int fd)

[PATCH 6.12.y 1/2] selftests: tls: add rekey tests

[Sasha Levin]

From: Sabrina Dubroca <sd@queasysnail.net>

[ Upstream commit 555f0edb9ff043196655a5b7cc65f67dfd05b530 ]

Test the kernel's ability to:
 - update the key (but not the version or cipher), only for TLS1.3
 - pause decryption after receiving a KeyUpdate message, until a new
   RX key has been provided
 - reflect the pause/non-readable socket in poll()

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 1c8629651cb5 ("tls: rx: restore msg_iter before TLS 1.3 optimistic retry")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/testing/selftests/net/tls.c | 458 ++++++++++++++++++++++++++++++
 1 file changed, 458 insertions(+)

diff --git a/tools/testing/selftests/net/tls.c b/tools/testing/selftests/net/tls.c
index f27a12d2a2c9..1264a20c1a04 100644
--- a/tools/testing/selftests/net/tls.c
+++ b/tools/testing/selftests/net/tls.c
@@ -1649,6 +1649,464 @@ TEST_F(tls, recv_efault)
 		EXPECT_EQ(memcmp(rec2, recv_mem + 9, ret - 9), 0);
 }
 
+#define TLS_RECORD_TYPE_HANDSHAKE      0x16
+/* key_update, length 1, update_not_requested */
+static const char key_update_msg[] = "\x18\x00\x00\x01\x00";
+static void tls_send_keyupdate(struct __test_metadata *_metadata, int fd)
+{
+	size_t len = sizeof(key_update_msg);
+
+	EXPECT_EQ(tls_send_cmsg(fd, TLS_RECORD_TYPE_HANDSHAKE,
+				(char *)key_update_msg, len, 0),
+		  len);
+}
+
+static void tls_recv_keyupdate(struct __test_metadata *_metadata, int fd, int flags)
+{
+	char buf[100];
+
+	EXPECT_EQ(tls_recv_cmsg(_metadata, fd, TLS_RECORD_TYPE_HANDSHAKE, buf, sizeof(buf), flags),
+		  sizeof(key_update_msg));
+	EXPECT_EQ(memcmp(buf, key_update_msg, sizeof(key_update_msg)), 0);
+}
+
+/* set the key to 0 then 1 for RX, immediately to 1 for TX */
+TEST_F(tls_basic, rekey_rx)
+{
+	struct tls_crypto_info_keys tls12_0, tls12_1;
+	char const *test_str = "test_message";
+	int send_len = strlen(test_str) + 1;
+	char buf[20];
+	int ret;
+
+	if (self->notls)
+		return;
+
+	tls_crypto_info_init(TLS_1_3_VERSION, TLS_CIPHER_AES_GCM_128,
+			     &tls12_0, 0);
+	tls_crypto_info_init(TLS_1_3_VERSION, TLS_CIPHER_AES_GCM_128,
+			     &tls12_1, 1);
+
+	ret = setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12_1, tls12_1.len);
+	ASSERT_EQ(ret, 0);
+
+	ret = setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12_0, tls12_0.len);
+	ASSERT_EQ(ret, 0);
+
+	ret = setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12_1, tls12_1.len);
+	EXPECT_EQ(ret, 0);
+
+	EXPECT_EQ(send(self->fd, test_str, send_len, 0), send_len);
+	EXPECT_EQ(recv(self->cfd, buf, send_len, 0), send_len);
+	EXPECT_EQ(memcmp(buf, test_str, send_len), 0);
+}
+
+/* set the key to 0 then 1 for TX, immediately to 1 for RX */
+TEST_F(tls_basic, rekey_tx)
+{
+	struct tls_crypto_info_keys tls12_0, tls12_1;
+	char const *test_str = "test_message";
+	int send_len = strlen(test_str) + 1;
+	char buf[20];
+	int ret;
+
+	if (self->notls)
+		return;
+
+	tls_crypto_info_init(TLS_1_3_VERSION, TLS_CIPHER_AES_GCM_128,
+			     &tls12_0, 0);
+	tls_crypto_info_init(TLS_1_3_VERSION, TLS_CIPHER_AES_GCM_128,
+			     &tls12_1, 1);
+
+	ret = setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12_0, tls12_0.len);
+	ASSERT_EQ(ret, 0);
+
+	ret = setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12_1, tls12_1.len);
+	ASSERT_EQ(ret, 0);
+
+	ret = setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12_1, tls12_1.len);
+	EXPECT_EQ(ret, 0);
+
+	EXPECT_EQ(send(self->fd, test_str, send_len, 0), send_len);
+	EXPECT_EQ(recv(self->cfd, buf, send_len, 0), send_len);
+	EXPECT_EQ(memcmp(buf, test_str, send_len), 0);
+}
+
+TEST_F(tls, rekey)
+{
+	char const *test_str_1 = "test_message_before_rekey";
+	char const *test_str_2 = "test_message_after_rekey";
+	struct tls_crypto_info_keys tls12;
+	int send_len;
+	char buf[100];
+
+	if (variant->tls_version != TLS_1_3_VERSION)
+		return;
+
+	/* initial send/recv */
+	send_len = strlen(test_str_1) + 1;
+	EXPECT_EQ(send(self->fd, test_str_1, send_len, 0), send_len);
+	EXPECT_EQ(recv(self->cfd, buf, send_len, 0), send_len);
+	EXPECT_EQ(memcmp(buf, test_str_1, send_len), 0);
+
+	/* update TX key */
+	tls_send_keyupdate(_metadata, self->fd);
+	tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+	EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), 0);
+
+	/* send after rekey */
+	send_len = strlen(test_str_2) + 1;
+	EXPECT_EQ(send(self->fd, test_str_2, send_len, 0), send_len);
+
+	/* can't receive the KeyUpdate without a control message */
+	EXPECT_EQ(recv(self->cfd, buf, send_len, 0), -1);
+
+	/* get KeyUpdate */
+	tls_recv_keyupdate(_metadata, self->cfd, 0);
+
+	/* recv blocking -> -EKEYEXPIRED */
+	EXPECT_EQ(recv(self->cfd, buf, sizeof(buf), 0), -1);
+	EXPECT_EQ(errno, EKEYEXPIRED);
+
+	/* recv non-blocking -> -EKEYEXPIRED */
+	EXPECT_EQ(recv(self->cfd, buf, sizeof(buf), MSG_DONTWAIT), -1);
+	EXPECT_EQ(errno, EKEYEXPIRED);
+
+	/* update RX key */
+	EXPECT_EQ(setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12, tls12.len), 0);
+
+	/* recv after rekey */
+	EXPECT_NE(recv(self->cfd, buf, send_len, 0), -1);
+	EXPECT_EQ(memcmp(buf, test_str_2, send_len), 0);
+}
+
+TEST_F(tls, rekey_fail)
+{
+	char const *test_str_1 = "test_message_before_rekey";
+	char const *test_str_2 = "test_message_after_rekey";
+	struct tls_crypto_info_keys tls12;
+	int send_len;
+	char buf[100];
+
+	/* initial send/recv */
+	send_len = strlen(test_str_1) + 1;
+	EXPECT_EQ(send(self->fd, test_str_1, send_len, 0), send_len);
+	EXPECT_EQ(recv(self->cfd, buf, send_len, 0), send_len);
+	EXPECT_EQ(memcmp(buf, test_str_1, send_len), 0);
+
+	/* update TX key */
+	tls_send_keyupdate(_metadata, self->fd);
+
+	if (variant->tls_version != TLS_1_3_VERSION) {
+		/* just check that rekey is not supported and return */
+		tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+		EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), -1);
+		EXPECT_EQ(errno, EBUSY);
+		return;
+	}
+
+	/* successful update */
+	tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+	EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), 0);
+
+	/* invalid update: change of version */
+	tls_crypto_info_init(TLS_1_2_VERSION, variant->cipher_type, &tls12, 1);
+	EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), -1);
+	EXPECT_EQ(errno, EINVAL);
+
+	/* invalid update (RX socket): change of version */
+	tls_crypto_info_init(TLS_1_2_VERSION, variant->cipher_type, &tls12, 1);
+	EXPECT_EQ(setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12, tls12.len), -1);
+	EXPECT_EQ(errno, EINVAL);
+
+	/* invalid update: change of cipher */
+	if (variant->cipher_type == TLS_CIPHER_AES_GCM_256)
+		tls_crypto_info_init(variant->tls_version, TLS_CIPHER_CHACHA20_POLY1305, &tls12, 1);
+	else
+		tls_crypto_info_init(variant->tls_version, TLS_CIPHER_AES_GCM_256, &tls12, 1);
+	EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), -1);
+	EXPECT_EQ(errno, EINVAL);
+
+	/* send after rekey, the invalid updates shouldn't have an effect */
+	send_len = strlen(test_str_2) + 1;
+	EXPECT_EQ(send(self->fd, test_str_2, send_len, 0), send_len);
+
+	/* can't receive the KeyUpdate without a control message */
+	EXPECT_EQ(recv(self->cfd, buf, send_len, 0), -1);
+
+	/* get KeyUpdate */
+	tls_recv_keyupdate(_metadata, self->cfd, 0);
+
+	/* recv blocking -> -EKEYEXPIRED */
+	EXPECT_EQ(recv(self->cfd, buf, sizeof(buf), 0), -1);
+	EXPECT_EQ(errno, EKEYEXPIRED);
+
+	/* recv non-blocking -> -EKEYEXPIRED */
+	EXPECT_EQ(recv(self->cfd, buf, sizeof(buf), MSG_DONTWAIT), -1);
+	EXPECT_EQ(errno, EKEYEXPIRED);
+
+	/* update RX key */
+	tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+	EXPECT_EQ(setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12, tls12.len), 0);
+
+	/* recv after rekey */
+	EXPECT_NE(recv(self->cfd, buf, send_len, 0), -1);
+	EXPECT_EQ(memcmp(buf, test_str_2, send_len), 0);
+}
+
+TEST_F(tls, rekey_peek)
+{
+	char const *test_str_1 = "test_message_before_rekey";
+	struct tls_crypto_info_keys tls12;
+	int send_len;
+	char buf[100];
+
+	if (variant->tls_version != TLS_1_3_VERSION)
+		return;
+
+	send_len = strlen(test_str_1) + 1;
+	EXPECT_EQ(send(self->fd, test_str_1, send_len, 0), send_len);
+
+	/* update TX key */
+	tls_send_keyupdate(_metadata, self->fd);
+	tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+	EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), 0);
+
+	EXPECT_EQ(recv(self->cfd, buf, sizeof(buf), MSG_PEEK), send_len);
+	EXPECT_EQ(memcmp(buf, test_str_1, send_len), 0);
+
+	EXPECT_EQ(recv(self->cfd, buf, send_len, 0), send_len);
+	EXPECT_EQ(memcmp(buf, test_str_1, send_len), 0);
+
+	/* can't receive the KeyUpdate without a control message */
+	EXPECT_EQ(recv(self->cfd, buf, send_len, MSG_PEEK), -1);
+
+	/* peek KeyUpdate */
+	tls_recv_keyupdate(_metadata, self->cfd, MSG_PEEK);
+
+	/* get KeyUpdate */
+	tls_recv_keyupdate(_metadata, self->cfd, 0);
+
+	/* update RX key */
+	EXPECT_EQ(setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12, tls12.len), 0);
+}
+
+TEST_F(tls, splice_rekey)
+{
+	int send_len = TLS_PAYLOAD_MAX_LEN / 2;
+	char mem_send[TLS_PAYLOAD_MAX_LEN];
+	char mem_recv[TLS_PAYLOAD_MAX_LEN];
+	struct tls_crypto_info_keys tls12;
+	int p[2];
+
+	if (variant->tls_version != TLS_1_3_VERSION)
+		return;
+
+	memrnd(mem_send, sizeof(mem_send));
+
+	ASSERT_GE(pipe(p), 0);
+	EXPECT_EQ(send(self->fd, mem_send, send_len, 0), send_len);
+
+	/* update TX key */
+	tls_send_keyupdate(_metadata, self->fd);
+	tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+	EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), 0);
+
+	EXPECT_EQ(send(self->fd, mem_send, send_len, 0), send_len);
+
+	EXPECT_EQ(splice(self->cfd, NULL, p[1], NULL, TLS_PAYLOAD_MAX_LEN, 0), send_len);
+	EXPECT_EQ(read(p[0], mem_recv, send_len), send_len);
+	EXPECT_EQ(memcmp(mem_send, mem_recv, send_len), 0);
+
+	/* can't splice the KeyUpdate */
+	EXPECT_EQ(splice(self->cfd, NULL, p[1], NULL, TLS_PAYLOAD_MAX_LEN, 0), -1);
+	EXPECT_EQ(errno, EINVAL);
+
+	/* peek KeyUpdate */
+	tls_recv_keyupdate(_metadata, self->cfd, MSG_PEEK);
+
+	/* get KeyUpdate */
+	tls_recv_keyupdate(_metadata, self->cfd, 0);
+
+	/* can't splice before updating the key */
+	EXPECT_EQ(splice(self->cfd, NULL, p[1], NULL, TLS_PAYLOAD_MAX_LEN, 0), -1);
+	EXPECT_EQ(errno, EKEYEXPIRED);
+
+	/* update RX key */
+	EXPECT_EQ(setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12, tls12.len), 0);
+
+	EXPECT_EQ(splice(self->cfd, NULL, p[1], NULL, TLS_PAYLOAD_MAX_LEN, 0), send_len);
+	EXPECT_EQ(read(p[0], mem_recv, send_len), send_len);
+	EXPECT_EQ(memcmp(mem_send, mem_recv, send_len), 0);
+}
+
+TEST_F(tls, rekey_peek_splice)
+{
+	char const *test_str_1 = "test_message_before_rekey";
+	struct tls_crypto_info_keys tls12;
+	int send_len;
+	char buf[100];
+	char mem_recv[TLS_PAYLOAD_MAX_LEN];
+	int p[2];
+
+	if (variant->tls_version != TLS_1_3_VERSION)
+		return;
+
+	ASSERT_GE(pipe(p), 0);
+
+	send_len = strlen(test_str_1) + 1;
+	EXPECT_EQ(send(self->fd, test_str_1, send_len, 0), send_len);
+
+	/* update TX key */
+	tls_send_keyupdate(_metadata, self->fd);
+	tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+	EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), 0);
+
+	EXPECT_EQ(recv(self->cfd, buf, sizeof(buf), MSG_PEEK), send_len);
+	EXPECT_EQ(memcmp(buf, test_str_1, send_len), 0);
+
+	EXPECT_EQ(splice(self->cfd, NULL, p[1], NULL, TLS_PAYLOAD_MAX_LEN, 0), send_len);
+	EXPECT_EQ(read(p[0], mem_recv, send_len), send_len);
+	EXPECT_EQ(memcmp(mem_recv, test_str_1, send_len), 0);
+}
+
+TEST_F(tls, rekey_getsockopt)
+{
+	struct tls_crypto_info_keys tls12;
+	struct tls_crypto_info_keys tls12_get;
+	socklen_t len;
+
+	tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 0);
+
+	len = tls12.len;
+	EXPECT_EQ(getsockopt(self->fd, SOL_TLS, TLS_TX, &tls12_get, &len), 0);
+	EXPECT_EQ(len, tls12.len);
+	EXPECT_EQ(memcmp(&tls12_get, &tls12, tls12.len), 0);
+
+	len = tls12.len;
+	EXPECT_EQ(getsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12_get, &len), 0);
+	EXPECT_EQ(len, tls12.len);
+	EXPECT_EQ(memcmp(&tls12_get, &tls12, tls12.len), 0);
+
+	if (variant->tls_version != TLS_1_3_VERSION)
+		return;
+
+	tls_send_keyupdate(_metadata, self->fd);
+	tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+	EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), 0);
+
+	tls_recv_keyupdate(_metadata, self->cfd, 0);
+	EXPECT_EQ(setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12, tls12.len), 0);
+
+	len = tls12.len;
+	EXPECT_EQ(getsockopt(self->fd, SOL_TLS, TLS_TX, &tls12_get, &len), 0);
+	EXPECT_EQ(len, tls12.len);
+	EXPECT_EQ(memcmp(&tls12_get, &tls12, tls12.len), 0);
+
+	len = tls12.len;
+	EXPECT_EQ(getsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12_get, &len), 0);
+	EXPECT_EQ(len, tls12.len);
+	EXPECT_EQ(memcmp(&tls12_get, &tls12, tls12.len), 0);
+}
+
+TEST_F(tls, rekey_poll_pending)
+{
+	char const *test_str = "test_message_after_rekey";
+	struct tls_crypto_info_keys tls12;
+	struct pollfd pfd = { };
+	int send_len;
+	int ret;
+
+	if (variant->tls_version != TLS_1_3_VERSION)
+		return;
+
+	/* update TX key */
+	tls_send_keyupdate(_metadata, self->fd);
+	tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+	EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), 0);
+
+	/* get KeyUpdate */
+	tls_recv_keyupdate(_metadata, self->cfd, 0);
+
+	/* send immediately after rekey */
+	send_len = strlen(test_str) + 1;
+	EXPECT_EQ(send(self->fd, test_str, send_len, 0), send_len);
+
+	/* key hasn't been updated, expect cfd to be non-readable */
+	pfd.fd = self->cfd;
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 0);
+
+	ret = fork();
+	ASSERT_GE(ret, 0);
+
+	if (ret) {
+		int pid2, status;
+
+		/* wait before installing the new key */
+		sleep(1);
+
+		/* update RX key while poll() is sleeping */
+		EXPECT_EQ(setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12, tls12.len), 0);
+
+		pid2 = wait(&status);
+		EXPECT_EQ(pid2, ret);
+		EXPECT_EQ(status, 0);
+	} else {
+		pfd.fd = self->cfd;
+		pfd.events = POLLIN;
+		EXPECT_EQ(poll(&pfd, 1, 5000), 1);
+
+		exit(!__test_passed(_metadata));
+	}
+}
+
+TEST_F(tls, rekey_poll_delay)
+{
+	char const *test_str = "test_message_after_rekey";
+	struct tls_crypto_info_keys tls12;
+	struct pollfd pfd = { };
+	int send_len;
+	int ret;
+
+	if (variant->tls_version != TLS_1_3_VERSION)
+		return;
+
+	/* update TX key */
+	tls_send_keyupdate(_metadata, self->fd);
+	tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+	EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), 0);
+
+	/* get KeyUpdate */
+	tls_recv_keyupdate(_metadata, self->cfd, 0);
+
+	ret = fork();
+	ASSERT_GE(ret, 0);
+
+	if (ret) {
+		int pid2, status;
+
+		/* wait before installing the new key */
+		sleep(1);
+
+		/* update RX key while poll() is sleeping */
+		EXPECT_EQ(setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12, tls12.len), 0);
+
+		sleep(1);
+		send_len = strlen(test_str) + 1;
+		EXPECT_EQ(send(self->fd, test_str, send_len, 0), send_len);
+
+		pid2 = wait(&status);
+		EXPECT_EQ(pid2, ret);
+		EXPECT_EQ(status, 0);
+	} else {
+		pfd.fd = self->cfd;
+		pfd.events = POLLIN;
+		EXPECT_EQ(poll(&pfd, 1, 5000), 1);
+		exit(!__test_passed(_metadata));
+	}
+}
+
 FIXTURE(tls_err)
 {
 	int fd, cfd;
-- 
2.53.0

[PATCH 6.12.y 2/2] tls: rx: restore msg_iter before TLS 1.3 optimistic retry

[Sasha Levin]

From: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr>

[ Upstream commit 1c8629651cb54f7b51db8fc0b1a9944e4a4b0f5e ]

tls_decrypt_sg() advances msg->msg_iter when it maps user pages for
the optimistic TLS 1.3 zero-copy path. If the decrypted record turns
out not to be unpadded application data, tls_decrypt_sw() retries into
a kernel skb, but leaves the iterator advanced.

The subsequent copy from the skb then writes decrypted bytes again at
a later point in the caller iovecs while recvmsg() reports only the
post-retry length. A TLS peer can trigger this after the receiver
enables TLS_RX_EXPECT_NO_PAD.

Revert the iterator by the number of bytes consumed by the optimistic
mapping before retrying without zero-copy.

Add a selftest which sends a TLS 1.3 control record with
TLS_RX_EXPECT_NO_PAD enabled and verifies that recvmsg() does not
overwrite later iovecs beyond the returned length.

Fixes: ce61327ce989 ("tls: rx: support optimistic decrypt to user buffer with TLS 1.3")
Cc: stable@vger.kernel.org
Signed-off-by: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr>
Link: https://patch.msgid.link/20260804125528.2139928-1-Jeremy.Jean@oss.cyber.gouv.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/tls/tls_sw.c                  |  2 ++
 tools/testing/selftests/net/tls.c | 57 +++++++++++++++++++++++++++++++
 2 files changed, 59 insertions(+)

diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
index 2b875369d523..5c55a16ed593 100644
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -1727,6 +1727,8 @@ tls_decrypt_sw(struct sock *sk, struct tls_context *tls_ctx,
 	/* If opportunistic TLS 1.3 ZC failed retry without ZC */
 	if (unlikely(darg->zc && prot->version == TLS_1_3_VERSION &&
 		     darg->tail != TLS_RECORD_TYPE_DATA)) {
+		iov_iter_revert(&msg->msg_iter, strp_msg(darg->skb)->full_len -
+				prot->overhead_size);
 		darg->zc = false;
 		if (!darg->tail)
 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXNOPADVIOL);
diff --git a/tools/testing/selftests/net/tls.c b/tools/testing/selftests/net/tls.c
index 1264a20c1a04..9388e77a1b21 100644
--- a/tools/testing/selftests/net/tls.c
+++ b/tools/testing/selftests/net/tls.c
@@ -1650,6 +1650,63 @@ TEST_F(tls, recv_efault)
 }
 
 #define TLS_RECORD_TYPE_HANDSHAKE      0x16
+
+TEST_F(tls_basic, recvmsg_nopad_retry_iov)
+{
+	char payload[32];
+	char first_iov[sizeof(payload)];
+	char later_iov[sizeof(payload) * 2];
+	char expected_later_iov[sizeof(later_iov)];
+	char cbuf[CMSG_SPACE(sizeof(char))];
+	struct tls_crypto_info_keys tls13;
+	struct iovec iov[] = {
+		{ .iov_base = first_iov, .iov_len = sizeof(first_iov) },
+		{ .iov_base = later_iov, .iov_len = sizeof(later_iov) },
+	};
+	struct msghdr msg = {
+		.msg_iov = iov,
+		.msg_iovlen = ARRAY_SIZE(iov),
+		.msg_control = cbuf,
+		.msg_controllen = sizeof(cbuf),
+	};
+	int one = 1;
+	int ret;
+	int i;
+
+	if (self->notls)
+		SKIP(return, "no TLS support");
+
+	tls_crypto_info_init(TLS_1_3_VERSION, TLS_CIPHER_AES_GCM_128,
+			     &tls13, 0);
+
+	ret = setsockopt(self->fd, SOL_TLS, TLS_TX, &tls13, tls13.len);
+	ASSERT_EQ(ret, 0);
+
+	ret = setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls13, tls13.len);
+	ASSERT_EQ(ret, 0);
+
+	ret = setsockopt(self->cfd, SOL_TLS, TLS_RX_EXPECT_NO_PAD,
+			 &one, sizeof(one));
+	ASSERT_EQ(ret, 0);
+
+	for (i = 0; i < sizeof(payload); i++)
+		payload[i] = 0x40 + i;
+	memset(first_iov, 0xa5, sizeof(first_iov));
+	memset(later_iov, 0x5a, sizeof(later_iov));
+	memset(expected_later_iov, 0x5a, sizeof(expected_later_iov));
+
+	/* A control record forces optimistic TLS 1.3 RX to retry. */
+	ret = tls_send_cmsg(self->fd, TLS_RECORD_TYPE_HANDSHAKE,
+			    payload, sizeof(payload), 0);
+	ASSERT_EQ(ret, sizeof(payload));
+
+	ret = recvmsg(self->cfd, &msg, 0);
+	ASSERT_EQ(ret, sizeof(payload));
+	EXPECT_EQ(memcmp(first_iov, payload, sizeof(payload)), 0);
+	EXPECT_EQ(memcmp(later_iov, expected_later_iov,
+			 sizeof(later_iov)), 0);
+}
+
 /* key_update, length 1, update_not_requested */
 static const char key_update_msg[] = "\x18\x00\x00\x01\x00";
 static void tls_send_keyupdate(struct __test_metadata *_metadata, int fd)
-- 
2.53.0

Re: [PATCH 6.12.y 1/2] selftests: tls: add rekey tests

[Sabrina Dubroca]

2026-08-19, 07:39:43 -0400, Sasha Levin wrote:
> From: Sabrina Dubroca <sd@queasysnail.net>
> 
> [ Upstream commit 555f0edb9ff043196655a5b7cc65f67dfd05b530 ]
> 
> Test the kernel's ability to:
>  - update the key (but not the version or cipher), only for TLS1.3
>  - pause decryption after receiving a KeyUpdate message, until a new
>    RX key has been provided
>  - reflect the pause/non-readable socket in poll()
> 
> Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
> Signed-off-by: David S. Miller <davem@davemloft.net>
> Stable-dep-of: 1c8629651cb5 ("tls: rx: restore msg_iter before TLS 1.3 optimistic retry")
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
>  tools/testing/selftests/net/tls.c | 458 ++++++++++++++++++++++++++++++
>  1 file changed, 458 insertions(+)

All of those rekey tests are going to fail if you don't take the rekey
implementation as well (which I hope isn't getting backported to any
stable kernels). You probably don't want that.

-- 
Sabrina

Re: [PATCH 6.12.y 1/2] selftests: tls: add rekey tests

[Sasha Levin]

On Wed, Aug 19, 2026 at 05:19:24PM +0200, Sabrina Dubroca wrote:
> All of those rekey tests are going to fail if you don't take the rekey
> implementation as well (which I hope isn't getting backported to any
> stable kernels). You probably don't want that.

You're right, and thanks for catching it.

To be unambiguous about what this actually affected: the 6.12.y series
you're replying to here was never queued, so there was nothing to drop
on 6.12. The same selftest had, however, already been queued for 6.6
from a separate 6.6.y posting, and that is what I've now dropped. Three
patches came out of the 6.6 queue:

  - selftests: tls: add rekey tests (555f0edb9ff0)
  - selftests: tls: add test with a partially invalid iov (dc54b813df63)
  - tls: rx: restore msg_iter before TLS 1.3 optimistic retry (1c8629651cb5)

On 6.6 it's worse than the tests failing - the selftest doesn't even
build. tls_crypto_info_init() only grew its key_generation argument in
b2e584aa3c71, which isn't in 6.6, so the ~20 four-argument call sites
the rekey patch adds fail to compile, and __test_passed() (69fe8ec4f673,
v6.9) is missing from 6.6's kselftest_harness.h. And of course the rekey
implementation itself (0471b1093e3a, 47069594e67e, 510128b30f2d) isn't
there, so tls_main.c still returns -EBUSY on the second setsockopt()
that every rekey test expects to succeed.

-- 
Thanks,
Sasha

Re: [PATCH 6.12.y 1/2] selftests: tls: add rekey tests

[Sabrina Dubroca]

2026-08-21, 12:51:30 -0400, Sasha Levin wrote:
> On Wed, Aug 19, 2026 at 05:19:24PM +0200, Sabrina Dubroca wrote:
> > All of those rekey tests are going to fail if you don't take the rekey
> > implementation as well (which I hope isn't getting backported to any
> > stable kernels). You probably don't want that.
> 
> You're right, and thanks for catching it.
> 
> To be unambiguous about what this actually affected: the 6.12.y series
> you're replying to here was never queued, so there was nothing to drop
> on 6.12. The same selftest had, however, already been queued for 6.6
> from a separate 6.6.y posting, and that is what I've now dropped. Three

Right. I saw something for 6.6 and kind of assumed that replying to
6.12 would be enough since it should be the exact same situation
there. I won't assume next time.

> patches came out of the 6.6 queue:
> 
>   - selftests: tls: add rekey tests (555f0edb9ff0)
>   - selftests: tls: add test with a partially invalid iov (dc54b813df63)
>   - tls: rx: restore msg_iter before TLS 1.3 optimistic retry (1c8629651cb5)

Sounds ok. I guess you could still backport the retry fix, you would
just get a trivial conflict on the selftest because the context
changed, but it's a minor behavioral bug.

> On 6.6 it's worse than the tests failing - the selftest doesn't even
> build. tls_crypto_info_init() only grew its key_generation argument in
> b2e584aa3c71, which isn't in 6.6, so the ~20 four-argument call sites

Yes, that was also part of the rekey series.

> the rekey patch adds fail to compile, and __test_passed() (69fe8ec4f673,
> v6.9) is missing from 6.6's kselftest_harness.h. And of course the rekey
> implementation itself (0471b1093e3a, 47069594e67e, 510128b30f2d) isn't
> there, so tls_main.c still returns -EBUSY on the second setsockopt()
> that every rekey test expects to succeed.

Thanks.

-- 
Sabrina