From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 060E02C1595; Sun, 7 Jun 2026 10:41:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780828887; cv=none; b=jFvgkq0Yn2z3x/75qC9w6DDKWj13tfJrEJ521W0ZqYE3koQ19IiAaDIQa2AjwUKb7px8JN5lmBx1enrrCkoGoa/b/vtbcIqUIa3oax0OKCirbQJSnH1N6ejPX74REX137YAW8vpN0VjaFtFGiQm5dZWXNtOBr0BxNZZ7MFPJU9k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780828887; c=relaxed/simple; bh=e3qF5TNgq/8FwsWLTJDVFTg0S3QzrKqLoxouKvCLvjM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=S/90bq0HOReuqz2uR64RmrMoTXEVB6r237OMsKlH/3GcMc9u75klwOig8wUTLVY2bJtAbmDKtBnJMuIr5Y5RTE1qSPmo7HnwP/zDSMvzvN905+IgvmUVXkqq0wQqtz8zrC153CNnnH4s7y66FOsBqplo4OD2cFIo8IcnaJepGMc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=jts7goZ5; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="jts7goZ5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 561531F00893; Sun, 7 Jun 2026 10:41:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780828885; bh=SKTARaohvO3beBSjEdFLP0jj7IHZh4ez3cIBT2rn9N4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=jts7goZ5UpNKQcWPDzldtuxmSWxt1Bx1aKZWvBpfGfY+j2BlzGh81qka6DVdAf22f SUU6Nq1A4s2mhOP8JGYoozrIFJLixu68cH7SE//W50TYmcOooKjCDjvr0EPNWLHIpz h8aGp3em5CP/YAg6QjvkzqCQPNoKKdp5o1rygg7o= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Simon Horman , Ashutosh Desai , David Heidelberg Subject: [PATCH 6.18 199/315] nfc: hci: fix out-of-bounds read in HCP header parsing Date: Sun, 7 Jun 2026 11:59:46 +0200 Message-ID: <20260607095734.880577528@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260607095727.528828913@linuxfoundation.org> References: <20260607095727.528828913@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ashutosh Desai commit f040e590c035bfd9553fe79ee9585caf1b14d67b upstream. Both nfc_hci_recv_from_llc() and nci_hci_data_received_cb() read packet->header from skb->data at function entry without first checking that the buffer holds at least one byte. A malicious NFC peer can send a 0-byte HCP frame that passes through the SHDLC layer and reaches these functions, causing an out-of-bounds heap read of packet->header. The same 0-byte frame, if queued as a non-final fragment, also causes the reassembly loop to underflow msg_len to UINT_MAX, triggering skb_over_panic() when the reassembled skb is written. Fix this by adding a pskb_may_pull() check at the entry of each function before packet->header is first accessed. The existing pskb_may_pull() checks before the reassembled hcp_skb is cast to struct hcp_packet remain in place to guard the 2-byte HCP message header. Fixes: 8b8d2e08bf0d ("NFC: HCI support") Fixes: 11f54f228643 ("NFC: nci: Add HCI over NCI protocol support") Cc: stable@vger.kernel.org Reviewed-by: Simon Horman Signed-off-by: Ashutosh Desai Link: https://patch.msgid.link/20260505170712.96560-1-ashutoshdesai993@gmail.com Signed-off-by: David Heidelberg Signed-off-by: Greg Kroah-Hartman --- net/nfc/hci/core.c | 10 ++++++++++ net/nfc/nci/hci.c | 10 ++++++++++ 2 files changed, 20 insertions(+) --- a/net/nfc/hci/core.c +++ b/net/nfc/hci/core.c @@ -861,6 +861,11 @@ static void nfc_hci_recv_from_llc(struct struct sk_buff *frag_skb; int msg_len; + if (!pskb_may_pull(skb, NFC_HCI_HCP_PACKET_HEADER_LEN)) { + kfree_skb(skb); + return; + } + packet = (struct hcp_packet *)skb->data; if ((packet->header & ~NFC_HCI_FRAGMENT) == 0) { skb_queue_tail(&hdev->rx_hcp_frags, skb); @@ -904,6 +909,11 @@ static void nfc_hci_recv_from_llc(struct * unblock waiting cmd context. Otherwise, enqueue to dispatch * in separate context where handler can also execute command. */ + if (!pskb_may_pull(hcp_skb, NFC_HCI_HCP_HEADER_LEN)) { + kfree_skb(hcp_skb); + return; + } + packet = (struct hcp_packet *)hcp_skb->data; type = HCP_MSG_GET_TYPE(packet->message.header); if (type == NFC_HCI_HCP_RESPONSE) { --- a/net/nfc/nci/hci.c +++ b/net/nfc/nci/hci.c @@ -439,6 +439,11 @@ void nci_hci_data_received_cb(void *cont return; } + if (!pskb_may_pull(skb, NCI_HCI_HCP_PACKET_HEADER_LEN)) { + kfree_skb(skb); + return; + } + packet = (struct nci_hcp_packet *)skb->data; if ((packet->header & ~NCI_HCI_FRAGMENT) == 0) { skb_queue_tail(&ndev->hci_dev->rx_hcp_frags, skb); @@ -482,6 +487,11 @@ void nci_hci_data_received_cb(void *cont * unblock waiting cmd context. Otherwise, enqueue to dispatch * in separate context where handler can also execute command. */ + if (!pskb_may_pull(hcp_skb, NCI_HCI_HCP_HEADER_LEN)) { + kfree_skb(hcp_skb); + return; + } + packet = (struct nci_hcp_packet *)hcp_skb->data; type = NCI_HCP_MSG_GET_TYPE(packet->message.header); if (type == NCI_HCI_HCP_RESPONSE) {