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 7722228FFFB; Thu, 9 Apr 2026 15:18:23 +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=1775747903; cv=none; b=IYsvfDQlvvefge94MMFZdnCrcUNnzWgCShlJwxwo2HBWFqq0yHvK9aXOdJ5SS5gfST3GPP9+MAioycG4+zwS4W/o9Z/HF6Sa8PEq2srwquGozH0OeT2msjTQo22xd0BO/uDsAnc6/K+5JG5U6tEUFIgGcHQrHZs5h86tt5vVQ94= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775747903; c=relaxed/simple; bh=COPLr3j3eltzdDcRfB/ZCPTVTVfPv3jxkW/ugyXwMBM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bzWhBtFTPWmJAlapDV82CK0YT/Ln4a1CtAIr39PpcxZIG/KF45k/ZHPIRYdx2l316/Pkl+OVSQzw+SBzxLUb+hE9v5i8yE/v0XOVlZk/VEu/rz8qaQelWxuL3lOTF1aBERgQ7gQwQ5HpuYLYh/00fSyHHolktlyi6Mc04Zyp3Y0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ETWY7FRZ; 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="ETWY7FRZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B41BAC4CEF7; Thu, 9 Apr 2026 15:18:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1775747903; bh=COPLr3j3eltzdDcRfB/ZCPTVTVfPv3jxkW/ugyXwMBM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ETWY7FRZ+hhtUnu8lsJnY9xyRyFXV7RuyVddIQUQGS4isqJf1NyjUmgFppL2/s22O Xg1WbJXu+XulMkJnGDvpDwXrnZ/Hel8pQVKOK+RxcueqGmaz5YrBPr79LNZMNvKFrU puzj+nHkiNW2rxv9KEQDxru7271jGofmvr+6ASks= From: Greg Kroah-Hartman To: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Greg Kroah-Hartman , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Kees Cook , Thierry Escande , Samuel Ortiz , stable Subject: [PATCH net 2/2] NFC: digital: Bounds check Felica response before sensf_res memcpy Date: Thu, 9 Apr 2026 17:18:15 +0200 Message-ID: <2026040913-rearrange-unseeing-fa85@gregkh> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026040913-figure-seducing-bd3f@gregkh> References: <2026040913-figure-seducing-bd3f@gregkh> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1903; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=COPLr3j3eltzdDcRfB/ZCPTVTVfPv3jxkW/ugyXwMBM=; b=owGbwMvMwCRo6H6F97bub03G02pJDJnXD5vNjri/vz9UaN/XrLCKOWwbj/S1WmxfxHjUbU+Ec qL31xnvOmJZGASZGGTFFFm+bOM5ur/ikKKXoe1pmDmsTCBDGLg4BWAinPcY5kqVTdoZN7edzT9b Nj3b7Xi902qRbIb5iT377qw6cuxD8gOmOS/XL5gi/PCkFQA= X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit A malicious NFC peer can send a SENSF_RES that is longer than the NFC_SENSF_RES_MAXSIZE (18 byte) sensf_res field in the onstack struct nfc_target. digital_in_recv_sensf_res() validates that the response is at least DIGITAL_SENSF_RES_MIN_LENGTH bytes but applies no upper bound before memcpy(target.sensf_res, sensf_res, resp->len) is called, allowing a stack buffer overflow with attacker-controlled length and content. Commit e329e71013c9 ("NFC: nci: Bounds check struct nfc_target arrays") fixed identical missing checks for the same target->sensf_res field on the NCI path; the Digital Protocol path was never patched. Fix this all up by just rejecting responses that exceed NFC_SENSF_RES_MAXSIZE. Cc: "David S. Miller" Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Paolo Abeni Cc: Simon Horman Cc: Greg Kroah-Hartman Cc: Kees Cook Cc: Thierry Escande Cc: Samuel Ortiz Fixes: 8c0695e4998d ("NFC Digital: Add NFC-F technology support") Cc: stable Assisted-by: gregkh_clanker_t1000 Signed-off-by: Greg Kroah-Hartman --- net/nfc/digital_technology.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/nfc/digital_technology.c b/net/nfc/digital_technology.c index ae63c5eb06fa..e18bdb231352 100644 --- a/net/nfc/digital_technology.c +++ b/net/nfc/digital_technology.c @@ -774,6 +774,11 @@ static void digital_in_recv_sensf_res(struct nfc_digital_dev *ddev, void *arg, skb_pull(resp, 1); + if (resp->len > NFC_SENSF_RES_MAXSIZE) { + rc = -EPROTO; + goto exit; + } + memset(&target, 0, sizeof(struct nfc_target)); sensf_res = (struct digital_sensf_res *)resp->data; -- 2.53.0