From nobody Mon Sep 28 23:12:45 2026 Received: from cstnet.cn (smtp25.cstnet.cn [159.226.251.25]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3077323643F; Sat, 15 Aug 2026 13:48:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.25 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786801716; cv=none; b=c5Ar6IK/7o4lThzsCXzNGFFB6TxUINOl3Tcon/2NFBqqeh5u5QBJspril6c9fOy+l4fwZU1TGij5t2hdP8qxXmyXQZoN0Ah6iI0cWiSaTq8HgQi9BEXs8qzvhCYsc9v1REnGcD4g0MYmiAINhhfmuk4fSyyaVpTlGXzXCF1T/OE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786801716; c=relaxed/simple; bh=7UV2D4vpN/KBruWZwdioP8alSCGT965QmckpccyECIc=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=r8gszftMj2m+cIn2iH4JFRijMeWu/MdDtaHtI2My7WXdrxgxAWI6myHGIJky52OB8oX+0jqz/AQ/KgRRkZMq0pHjV4sGHLdVcnAvtU5uGyqoPj4H753CiAnF0HMF/pEA0FN7aEoJTMeGGKUEfxi49VKINbuqvHrW9uUrRJLzIGQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.25 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from localhost.localdomain (unknown [111.196.241.250]) by APP-05 (Coremail) with SMTP id zQCowAAHcTspboBqB13RBQ--.2466S2; Sat, 15 Aug 2026 21:48:25 +0800 (CST) From: Pengpeng Hou To: david@ixit.cz Cc: Pengpeng Hou , Kees Cook , Doruk Tan Ozturk , Eric Lapuyade , Samuel Ortiz , oe-linux-nfc@lists.linux.dev, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH v3] nfc: microread: validate target discovery payload lengths Date: Sat, 15 Aug 2026 21:48:25 +0800 Message-ID: <20260815134825.48593-1-pengpeng@iscas.ac.cn> X-Mailer: git-send-email 2.50.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: zQCowAAHcTspboBqB13RBQ--.2466S2 X-Coremail-Antispam: 1UD129KBjvJXoWxJFyrZrWkKFyDKw1xCrW3Jrb_yoWrAr1Dpa yUWr1DKrW5JrW7Gw13ZFn7ZF1UJw4xuwsF9F1xJwsaya1Yk34DJas3W3y2vF4UAF98urW2 kF1vv39xGa9rAa7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUkE14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26r4j6ryUM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26F4j 6r4UJwA2z4x0Y4vEx4A2jsIE14v26F4UJVW0owA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_Cr 1j6rxdM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj 6xIIjxv20xvE14v26r126r1DMcIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr 0_Gr1lF7xvr2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7MxkF7I0En4kS14v2 6r1q6r43MxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrV AFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVWUtVW8ZwCI c40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267 AKxVWxJVW8Jr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j 6r4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUL0e dUUUUU= X-CM-SenderInfo: pshqw1xhqjqxpvfd2hldfou0/ Content-Type: text/plain; charset="utf-8" microread_target_discovered() parses target discovery payloads from skb->data according to the HCI gate. The fixed field offsets and UID copies were checked only against the destination nfc_target buffers, not against the actual skb length. Validate that each gate-specific payload contains the fixed fields and UID bytes before reading or copying them. Fixes: cfad1ba87150 ("NFC: Initial support for Inside Secure microread") Cc: stable@vger.kernel.org Assisted-by: Codex:gpt-5 Signed-off-by: Pengpeng Hou --- Changes since v2: https://lore.kernel.org/all/20260723103508.1-microread-v2-pengpeng@iscas.ac= .cn/ - no code changes - revalidate the patch against current mainline - add the required coding-assistant attribution Changes since v1: https://lore.kernel.org/all/20260701053709.45176-1-pengpeng@iscas.ac.cn/ - add the Fixes tag and stable Cc requested during review - rebase onto the current net tree drivers/nfc/microread/microread.c | 31 +++++++++++++++++++++++++++++-- 1 file changed, 29 insertions(+), 2 deletions(-) diff --git a/drivers/nfc/microread/microread.c b/drivers/nfc/microread/micr= oread.c index 4149c5d735bd..dfa2490db545 100644 --- a/drivers/nfc/microread/microread.c +++ b/drivers/nfc/microread/microread.c @@ -483,13 +483,19 @@ static void microread_target_discovered(struct nfc_hc= i_dev *hdev, u8 gate, =20 switch (gate) { case MICROREAD_GATE_ID_MREAD_ISO_A: + if (skb->len <=3D MICROREAD_EMCF_A_LEN) { + r =3D -EINVAL; + goto exit_free; + } + targets->supported_protocols =3D nfc_hci_sak_to_protocol(skb->data[MICROREAD_EMCF_A_SAK]); targets->sens_res =3D be16_to_cpu(*(u16 *)&skb->data[MICROREAD_EMCF_A_ATQA]); targets->sel_res =3D skb->data[MICROREAD_EMCF_A_SAK]; targets->nfcid1_len =3D skb->data[MICROREAD_EMCF_A_LEN]; - if (targets->nfcid1_len > sizeof(targets->nfcid1)) { + if (targets->nfcid1_len > sizeof(targets->nfcid1) || + targets->nfcid1_len > skb->len - MICROREAD_EMCF_A_UID) { r =3D -EINVAL; goto exit_free; } @@ -497,13 +503,19 @@ static void microread_target_discovered(struct nfc_hc= i_dev *hdev, u8 gate, targets->nfcid1_len); break; case MICROREAD_GATE_ID_MREAD_ISO_A_3: + if (skb->len <=3D MICROREAD_EMCF_A3_LEN) { + r =3D -EINVAL; + goto exit_free; + } + targets->supported_protocols =3D nfc_hci_sak_to_protocol(skb->data[MICROREAD_EMCF_A3_SAK]); targets->sens_res =3D be16_to_cpu(*(u16 *)&skb->data[MICROREAD_EMCF_A3_ATQA]); targets->sel_res =3D skb->data[MICROREAD_EMCF_A3_SAK]; targets->nfcid1_len =3D skb->data[MICROREAD_EMCF_A3_LEN]; - if (targets->nfcid1_len > sizeof(targets->nfcid1)) { + if (targets->nfcid1_len > sizeof(targets->nfcid1) || + targets->nfcid1_len > skb->len - MICROREAD_EMCF_A3_UID) { r =3D -EINVAL; goto exit_free; } @@ -511,11 +523,21 @@ static void microread_target_discovered(struct nfc_hc= i_dev *hdev, u8 gate, targets->nfcid1_len); break; case MICROREAD_GATE_ID_MREAD_ISO_B: + if (skb->len < MICROREAD_EMCF_B_UID + 4) { + r =3D -EINVAL; + goto exit_free; + } + targets->supported_protocols =3D NFC_PROTO_ISO14443_B_MASK; memcpy(targets->nfcid1, &skb->data[MICROREAD_EMCF_B_UID], 4); targets->nfcid1_len =3D 4; break; case MICROREAD_GATE_ID_MREAD_NFC_T1: + if (skb->len < MICROREAD_EMCF_T1_UID + 4) { + r =3D -EINVAL; + goto exit_free; + } + targets->supported_protocols =3D NFC_PROTO_JEWEL_MASK; targets->sens_res =3D le16_to_cpu(*(u16 *)&skb->data[MICROREAD_EMCF_T1_ATQA]); @@ -523,6 +545,11 @@ static void microread_target_discovered(struct nfc_hci= _dev *hdev, u8 gate, targets->nfcid1_len =3D 4; break; case MICROREAD_GATE_ID_MREAD_NFC_T3: + if (skb->len < MICROREAD_EMCF_T3_UID + 8) { + r =3D -EINVAL; + goto exit_free; + } + targets->supported_protocols =3D NFC_PROTO_FELICA_MASK; memcpy(targets->nfcid1, &skb->data[MICROREAD_EMCF_T3_UID], 8); targets->nfcid1_len =3D 8; base-commit: dac3e89a2c90c2feeb471e1f22a2512ad424b792 --=20 2.50.1 (Apple Git-155)