From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 335F83AC0D2; Mon, 23 Mar 2026 13:55:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774274134; cv=none; b=SVALcHmv3Ae/ehklxxMu6EERWZTgg5G9Wum2I129bP4tBXf+DtlbxfV8g1pcWm1GqlNzPVm1NFWCwFo/ctfHKN/ioDTP90rPTdXKxzhepUq2LcC9RQlLbkZlAw2Lx86C6pfkWhGcUzeNStmP2Zlz+erep31gyyttlcGPuCEniVU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774274134; c=relaxed/simple; bh=WSeVqXUyh9l1DDYVdWrOVFqeiHzXQtFs8AG2NTsqkD0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=eK2f2i+bDNuRFWtev/U0v++JzmTKLF8exfRpB07suoT388KhcsjObbrBqoO7uqgmwYDhzon5RXGcYZ4vo+8m/++trRREZiq1JmWgaY78O52TTYlcdlsIgnRhl5QFQvxZT5m0noyonDX3mPcDDK3DipCysHviVBsPe7yZ3e6sbks= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=SxA+2YPk; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="SxA+2YPk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A9A10C4CEF7; Mon, 23 Mar 2026 13:55:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1774274134; bh=WSeVqXUyh9l1DDYVdWrOVFqeiHzXQtFs8AG2NTsqkD0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SxA+2YPk61JtFb4Lgpa6IKBJEzuZDWE6bRR1wqNBptyzvF6roBvGkWrkM9nG/YVkx 9aTLTVXYarVTAn3+VUiuK47b7SHh3ANqgdBBu4lhTDG9qdKPLeQoLz1leOWHADcAOy moyoj25BHPP2ZfG8m6p7yL36cF31R9OJH59sS1JM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Christian Eggers , Luiz Augusto von Dentz , Sasha Levin Subject: [PATCH 6.19 118/220] Bluetooth: LE L2CAP: Disconnect if received packets SDU exceeds IMTU Date: Mon, 23 Mar 2026 14:44:55 +0100 Message-ID: <20260323134508.332575668@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260323134504.575022936@linuxfoundation.org> References: <20260323134504.575022936@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Christian Eggers [ Upstream commit e1d9a66889867c232657a9b6f25d451d7c3ab96f ] Core 6.0, Vol 3, Part A, 3.4.3: "If the SDU length field value exceeds the receiver's MTU, the receiver shall disconnect the channel..." This fixes L2CAP/LE/CFC/BV-26-C (running together with 'l2test -r -P 0x0027 -V le_public -I 100'). Fixes: aac23bf63659 ("Bluetooth: Implement LE L2CAP reassembly") Signed-off-by: Christian Eggers Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin --- net/bluetooth/l2cap_core.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 319c87bd795d5..1618fe98dce71 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -6654,8 +6654,10 @@ static int l2cap_ecred_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb) return -ENOBUFS; } - if (chan->imtu < skb->len) { - BT_ERR("Too big LE L2CAP PDU"); + if (skb->len > chan->imtu) { + BT_ERR("Too big LE L2CAP PDU: len %u > %u", skb->len, + chan->imtu); + l2cap_send_disconn_req(chan, ECONNRESET); return -ENOBUFS; } @@ -6681,7 +6683,9 @@ static int l2cap_ecred_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb) sdu_len, skb->len, chan->imtu); if (sdu_len > chan->imtu) { - BT_ERR("Too big LE L2CAP SDU length received"); + BT_ERR("Too big LE L2CAP SDU length: len %u > %u", + skb->len, sdu_len); + l2cap_send_disconn_req(chan, ECONNRESET); err = -EMSGSIZE; goto failed; } -- 2.51.0