From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794049590; b=AA08gO3rIP6IUoVqkYVNU8fEORjpM7M7Dwr0CWpNZNPGODqpTlAj7wyBjt3qrTTXO02/ 9RsTK9moooxsm+T8LqsrD0pXR8Gyrff45r7mw+I9aDY1A1cZ8X/zdvB5zY+w69U1MiBno nIW07DhVyao0QwBMsb0t4JNxOPsrARLCrzyysoeiwYrXJP7tt/bRG0+CM9BomMFeamaVu VNCtfqVdO8J2ALREM1qNT6K1UO2CQoHyNJId/Pl6wJH8SdCpqwsowAmcjClI+MWx6u61X p01Mue1YCaATD5Zi7ZwxYf0sq4LSWQv7g6ihfTeujcHk7Q5dH8pfnmaM5p/AE56osJw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794049590; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: MIME-Version:Content-Type:Content-Transfer-Encoding; bh=SZFPMwEDbs3We1WhDCdfhsOljtxJsg567NavirOZB4Q=; b=XhNysxRevC4S7BN/ZF4oYDrj2V+YGVBCYOLGmL++pcccvak7LezbLbG4dHmt8TQV0gzD teROHpKfEpALwBRQ9NwrKny09V59O8HNyw0ChMcvXsORtIMBRwH+A9QnX6WOwXPmnsdd1 Ckla0R4Rt2lEq6nJhYWVFnJXz+M9v7hUFJeptDQscadI0SQYas5UHLHA/7xW1Y+1fqgxy OWcEvZ0CaM1WXm572atn1QyHUw+AhYEmWGSe/v1fzCMh0jZneNB7o+FEYH8TsErI03PuQ nrjrR8YseklqZTA7sXcbXkRX7lYmxCSEJBCcBfSKbKU6lBaKk/nSO+5JUv5aud2jSSg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=iU2Z8U63; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0A8F3606A326 for ; Sat, 7 Nov 2026 11:06:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=iU2Z8U63 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7DF791F0089F; Sat, 7 Nov 2026 11:06:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794049589; bh=SZFPMwEDbs3We1WhDCdfhsOljtxJsg567NavirOZB4Q=; h=From:To:Cc:Subject:Date; b=iU2Z8U636hFQb21XfPqECLUnBlTKdBc9NT+0p//i5BApVOP3ZPcVbHSRIeoy9Zd2J MOXtEcXucutg+ajAhF9lj4PQQKvnB11qMiR0n2KksWX07onzyHlNuJW06/neiiRmk3 aPXqYb/hDBeuTKP/aKzX8mJ9zuhvywH740qtcf5DMqNhuEaW05llgvcPozVTQlBslz 2RsqunrCVLWbN5cpUvMIvEV7TC8DaA7e0OAr6XGWekKve059Wnu7XfO2y4s1DVEuZZ VM8v7Ocq395LhVyODKuHO55b0tfYdRDk6p2DKpxPAo/QukJ2m4zBBJ084hhBnPD3vT 6TmLNUZllVJJA== From: Sasha Levin To: oss@fourdim.xyz, luiz.von.dentz@intel.com Cc: stable@vger.kernel.org Subject: FAILED: patch "[PATCH] Bluetooth: L2CAP: Reject signalling responses in invalid states" failed to apply to 5.15-stable tree Date: Sat, 7 Nov 2026 06:06:28 -0500 Message-ID: <20261107060628-failed-5.15-6320736af7dc@kernel.org> X-Mailer: git-send-email 2.53.0 X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The patch below does not apply to the 5.15-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 . 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-5.15.y git checkout FETCH_HEAD git cherry-pick -x 6320736af7dcb90da6ee9fd651ecc11c564d45b7 # git commit -s git send-email --to '' --in-reply-to '20261107060628-failed-5.15-6320736af7dc@kernel.org' --subject-prefix 'PATCH 5.15.y' 'HEAD^..' Thanks, Sasha ------------------ original commit in Linus's tree ------------------ >From 6320736af7dcb90da6ee9fd651ecc11c564d45b7 Mon Sep 17 00:00:00 2001 From: Siwei Zhang Date: Tue, 13 Oct 2026 11:36:34 -0400 Subject: [PATCH] Bluetooth: L2CAP: Reject signalling responses in invalid states A peer can send configuration messages while an incoming channel is in BT_CONNECT2, before the security or deferred accept gate has completed. A configuration response can then promote the channel to BT_CONNECTED. Configuration responses can also act on channels that are closing, and a late connection response can move a disconnecting channel back to BT_CONFIG. Accept connection responses only while waiting in BT_CONNECT. Answer configuration requests in BT_CONNECT2, but defer our own request until BT_CONFIG so configuration cannot complete before the gate. Ignore configuration responses outside BT_CONFIG and BT_CONNECTED, and only complete configuration in BT_CONFIG. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-5-5 Signed-off-by: Siwei Zhang Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/l2cap_core.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index c730da87734b3..eb55c16760a7e 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -4442,6 +4442,10 @@ static int l2cap_connect_create_rsp(struct l2cap_conn *conn, lockdep_assert_held(&chan->conn->lock); + /* Ignore a late response after the channel has left BT_CONNECT. */ + if (chan->state != BT_CONNECT) + goto done; + switch (result) { case L2CAP_CR_SUCCESS: if (__l2cap_get_chan_by_dcid(conn, dcid)) { @@ -4471,6 +4475,7 @@ static int l2cap_connect_create_rsp(struct l2cap_conn *conn, break; } +done: l2cap_chan_unlock(chan); l2cap_chan_put(chan); @@ -4608,7 +4613,13 @@ static inline int l2cap_config_req(struct l2cap_conn *conn, goto unlock; } - if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) { + /* A channel in BT_CONNECT2 has not passed security or userspace + * accept yet. Answer the peer's request, but hold our own until + * the channel reaches BT_CONFIG: the CONNECT2 -> CONFIG sites send + * it. Connected channels may also need to reconfigure. + */ + if ((chan->state == BT_CONFIG || chan->state == BT_CONNECTED) && + !test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) { u8 buf[64]; l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ, l2cap_build_conf_req(chan, buf, sizeof(buf)), buf); @@ -4661,6 +4672,10 @@ static inline int l2cap_config_rsp(struct l2cap_conn *conn, lockdep_assert_held(&chan->conn->lock); + /* Connected channels may also receive reconfiguration responses. */ + if (chan->state != BT_CONFIG && chan->state != BT_CONNECTED) + goto done; + switch (result) { case L2CAP_CONF_SUCCESS: l2cap_conf_rfc_get(chan, rsp->data, len); @@ -4728,6 +4743,9 @@ static inline int l2cap_config_rsp(struct l2cap_conn *conn, if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) { set_default_fcs(chan); + if (chan->state != BT_CONFIG) + goto done; + if (chan->mode == L2CAP_MODE_ERTM || chan->mode == L2CAP_MODE_STREAMING) err = l2cap_ertm_init(chan); -- 2.53.0