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 482113D4134; Wed, 8 Apr 2026 18:08:05 +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=1775671686; cv=none; b=pU4lDD807uikjXGT1ZvLdDe7Ob25Qe6U1vsqhqiYtHcpLvQxAqBtJ8o7ml16YMqJzdswuCl+ElBwpY2+StE/Gk/LC1yFALLRO/qjDupaM42ILuy0sRcIh9w4/J2VHaBjY259aQzw1VkKIuRrmcsCrZ2mHnWczcEE6W/MzbZfh7Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775671686; c=relaxed/simple; bh=QHulYtB3A25Hq/U6ZWQoT5KIYL0r5HIZvi86gTtb80A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Eb1VTgLA8O/IAWaOtv9Hd33p2mOih8YRmggaeyI1fGS2W4wdWFMnTrmeyieQLrVL3M1DlYhXpCm+1bFrycI2Ty9N8RoJ6Fot13n8ZOr2pZ/GZVD7ZK8Aksw5Pqx6Oy5rXw3qnvES1+h8MuECSA+c0hrD0hNT6ha8+1YL7itpTrM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=smuvenbs; 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="smuvenbs" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 85978C19421; Wed, 8 Apr 2026 18:08:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1775671685; bh=QHulYtB3A25Hq/U6ZWQoT5KIYL0r5HIZvi86gTtb80A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=smuvenbsXPjzEYi+O+w1QB5JdEoAzvdwUI8AicYOa+hDeOOBKVjbTnnXY0sLRueG6 EWLXJ3LrOjvzb9+qYWFqUSHTazVZ0s4pcDQrdMv1TF4MnWJ0w470m3cepGjOzv7pqG 8wwaIK8skoj1VAwudYwbQlji2tD4qA/QfHVTkvCc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Hyunwoo Kim , Luiz Augusto von Dentz , Sasha Levin Subject: [PATCH 6.1 029/312] Bluetooth: L2CAP: Validate PDU length before reading SDU length in l2cap_ecred_data_rcv() Date: Wed, 8 Apr 2026 19:59:06 +0200 Message-ID: <20260408175934.815899741@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260408175933.715315542@linuxfoundation.org> References: <20260408175933.715315542@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 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hyunwoo Kim [ Upstream commit c65bd945d1c08c3db756821b6bf9f1c4a77b29c6 ] l2cap_ecred_data_rcv() reads the SDU length field from skb->data using get_unaligned_le16() without first verifying that skb contains at least L2CAP_SDULEN_SIZE (2) bytes. When skb->len is less than 2, this reads past the valid data in the skb. The ERTM reassembly path correctly calls pskb_may_pull() before reading the SDU length (l2cap_reassemble_sdu, L2CAP_SAR_START case). Apply the same validation to the Enhanced Credit Based Flow Control data path. Fixes: aac23bf63659 ("Bluetooth: Implement LE L2CAP reassembly") Signed-off-by: Hyunwoo Kim Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin --- net/bluetooth/l2cap_core.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 3dfaf7044eddc..38e46f5175dad 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -7708,6 +7708,11 @@ static int l2cap_ecred_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb) if (!chan->sdu) { u16 sdu_len; + if (!pskb_may_pull(skb, L2CAP_SDULEN_SIZE)) { + err = -EINVAL; + goto failed; + } + sdu_len = get_unaligned_le16(skb->data); skb_pull(skb, L2CAP_SDULEN_SIZE); -- 2.51.0