From nobody Tue Sep 29 00:36:36 2026 Received: from cstnet.cn (smtp21.cstnet.cn [159.226.251.21]) (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 907D1435514 for ; Fri, 14 Aug 2026 08:02:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.21 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786694553; cv=none; b=hK/eBcHDUS6Jk6xMs6nYUCXZn6D+pOF0tJzDxbZZa/mEFW3hxid9NJOtPaWpxHQSjkzNTBkcYUzkVJYLv7R60vx0sIr7lukMhlJMrdlTUA/hCjL6N9TYt7t6AIYYOYXoFEGzWkR4Api8CcpQJ+JA/h89vTa2G6G1iU1/yER1WxI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786694553; c=relaxed/simple; bh=cRKX8OFIBj8FQaLWj4nuo0wp4mm4ZLiFp+AmnVRzh6s=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=jJd7S88DRCibSy/bFbSRpTzk2JMyiG9pAAUBHiW33q45yMAKSoSB5Jzs6a3DRAHrVG93ONZ+YS9jcx5leKXAnqv0thEJch7ugQmKbHC1J3LcvI8/rf4QSjNQEuagZkUMeyt9WtY6B/SgOLxnYbJDHMdRKuwfHLH/g3w5J9zIEvA= 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=159.226.251.21 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-01 (Coremail) with SMTP id qwCowACnffGIy35qW7eeBQ--.48856S2; Fri, 14 Aug 2026 16:02:17 +0800 (CST) From: Pengpeng Hou To: Rahul Pathak , Anup Patel , Jassi Brar Cc: Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Pengpeng Hou Subject: [PATCH v2] mailbox: riscv-sbi-mpxy: validate RPMI notification lengths Date: Fri, 14 Aug 2026 16:02:15 +0800 Message-ID: <20260814080215.21753-1-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-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: qwCowACnffGIy35qW7eeBQ--.48856S2 X-Coremail-Antispam: 1UD129KBjvJXoWxZFyktr43Kw4fJrWfCr13CFg_yoW5GF4rpF W7Ka4FyrWUtrnrZ3sxX3WkZayUW3s3JF9rKa4qy34FvFsxWr1UJFWDta4jq3WFyFW7Jryx twsYqFs8Z34DZa7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9I14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26ryj6F1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4U JVWxJr1l84ACjcxK6I8E87Iv67AKxVWxJr0_GcWl84ACjcxK6I8E87Iv6xkF7I0E14v26r xl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj 6xIIjxv20xvE14v26r1q6rW5McIj6I8E87Iv67AKxVW8JVWxJwAm72CE4IkC6x0Yz7v_Jr 0_Gr1lF7xvr2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7M4IIrI8v6xkF7I0E 8cxan2IY04v7MxkF7I0En4kS14v26r1q6r43MxAIw28IcxkI7VAKI48JMxC20s026xCaFV Cjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWl x4CE17CEb7AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r4j6r yUMIIF0xvE2Ix0cI8IcVCY1x0267AKxVWxJVW8Jr1lIxAIcVCF04k26cxKx2IYs7xG6r1j 6r1xMIIF0xvEx4A2jsIE14v26r4j6F4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr1j6F4UJb IYCTnIWIevJa73UjIFyTuYvjfU5byZUUUUU X-CM-SenderInfo: pshqw1xhqjqxpvfd2hldfou0/ The SBI return value controls how many bytes are copied from shared memory into the RPMI notification buffer. It is not validated against the negotiated shared-memory size before that copy. The event walker also uses a reversed loop condition and can inspect a short event record. Validate the complete notification length before copying it, iterate only while a full event header remains, and stop when a declared event payload extends beyond the copied notification data. Fixes: bf3022a4eb11 ("mailbox: Add RISC-V SBI message proxy (MPXY) based ma= ilbox driver") Assisted-by: Codex:gpt-5 Signed-off-by: Pengpeng Hou --- Changes since v1: https://lore.kernel.org/all/20260706092108.78340-1-pengpe= ng@iscas.ac.cn/ - validate the SBI-reported total before copying shared memory - fix the inverted full-event-header loop condition - validate each event payload extent before dispatch The shared-memory and event extents were reviewed statically; malformed RPMI firmware data was not injected. drivers/mailbox/riscv-sbi-mpxy-mbox.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/mailbox/riscv-sbi-mpxy-mbox.c b/drivers/mailbox/riscv-= sbi-mpxy-mbox.c index 7c9c006b7244..714f7fb97a2f 100644 --- a/drivers/mailbox/riscv-sbi-mpxy-mbox.c +++ b/drivers/mailbox/riscv-sbi-mpxy-mbox.c @@ -314,8 +314,13 @@ static int mpxy_get_notifications(u32 channel_id, channel_id, 0, 0, 0, 0, 0); if (sret.error) goto err_put_cpu; + if (sret.value < 0 || mpxy_shmem_size < sizeof(*notif_data) || + sret.value > mpxy_shmem_size - sizeof(*notif_data)) { + put_cpu(); + return -EOVERFLOW; + } =20 - memcpy(notif_data, mpxy->shmem, sret.value + 16); + memcpy(notif_data, mpxy->shmem, sret.value + sizeof(*notif_data)); *events_data_len =3D sret.value; =20 err_put_cpu: @@ -480,11 +485,14 @@ static void mpxy_mbox_peek_rpmi_data(struct mbox_chan= *chan, struct rpmi_mbox_message msg; unsigned long pos =3D 0; =20 - while (pos < events_data_len && (events_data_len - pos) <=3D sizeof(*even= t)) { + while (events_data_len - pos >=3D sizeof(*event)) { event =3D (struct rpmi_notification_event *)(notif->events_data + pos); =20 msg.type =3D RPMI_MBOX_MSG_TYPE_NOTIFICATION_EVENT; msg.notif.event_datalen =3D le16_to_cpu(event->event_datalen); + if (msg.notif.event_datalen > + events_data_len - pos - sizeof(*event)) + break; msg.notif.event_id =3D event->event_id; msg.notif.event_data =3D event->event_data; msg.error =3D 0; --=20 2.50.1 (Apple Git-155)