From nobody Mon Dec 1 23:02:20 2025 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 D1E802701DA for ; Wed, 26 Nov 2025 16:36:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764174975; cv=none; b=LDy6TBwJUCq+eCMkFhRsgvqHnJzHqtDvEOL8nKbddSBBxgnmjml4KPrkCGuK39XlPx198a8IDybfZVlKviZLKbsHmCyTUsxFM61GelG7K0GbiypDaiL21e/tsU7Ns+ci8EYTrOtZX+SZV5q5I1nfQ2vIvvcDXB0FwKIxLU0iL5s= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764174975; c=relaxed/simple; bh=hwN0X3MlXRgzLf/i/Ti7PYZd5dSD1XSxvGZQlmoWXRM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=amxrwgmNhzwJ3+bUXEaPscB1Ysk+IImCW9VA4A8YdacLQqxXVbqsu8jgr7NuQtbcUy9r4+8okQ8kg3TzQGd7UL676YX75gMFpP6WkY5aQlhWaY210wSIwZ8tgwkyCRd3dibVRfOTRkh5cRSz1QUWj7Bey2jwtAMbeARjnJgB5ZM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=TULbnYAS; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="TULbnYAS" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1764174972; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=n8ULdLo4b3ORYhVubgD3gy7oPbpY6qArrsrgQiRkmsY=; b=TULbnYASTV47y4KeV8rkkp+4GMQDFlDKS9sUZ8IGcEJNlJ8yVob4meQdTVGmMH4rNvg6mA uTVRxh3a1qEWAxXEicY+mv1iZr+4T+QdhW40SQxkfxGOLPsEf8V2wJSdoZPld3F2RuAa9O 3YXmWOYhJdo/JOJarNN6U4Cvv/HGxao= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-137-9p40aK1TNFeth8KEkFpF8g-1; Wed, 26 Nov 2025 11:36:09 -0500 X-MC-Unique: 9p40aK1TNFeth8KEkFpF8g-1 X-Mimecast-MFC-AGG-ID: 9p40aK1TNFeth8KEkFpF8g_1764174967 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 33FAA1800451; Wed, 26 Nov 2025 16:36:07 +0000 (UTC) Received: from localhost (unknown [10.2.16.50]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 6C4A319560A2; Wed, 26 Nov 2025 16:36:05 +0000 (UTC) From: Stefan Hajnoczi To: linux-block@vger.kernel.org Cc: "Martin K. Petersen" , linux-kernel@vger.kernel.org, "James E.J. Bottomley" , Mike Christie , Jens Axboe , linux-nvme@lists.infradead.org, Keith Busch , Sagi Grimberg , linux-scsi@vger.kernel.org, Christoph Hellwig , Stefan Hajnoczi Subject: [PATCH 1/4] scsi: sd: reject invalid pr_read_keys() num_keys values Date: Wed, 26 Nov 2025 11:35:57 -0500 Message-ID: <20251126163600.583036-2-stefanha@redhat.com> In-Reply-To: <20251126163600.583036-1-stefanha@redhat.com> References: <20251126163600.583036-1-stefanha@redhat.com> 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-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 Content-Type: text/plain; charset="utf-8" The pr_read_keys() interface has a u32 num_keys parameter. The SCSI PERSISTENT RESERVE IN command has a maximum READ KEYS service action size of 65536 bytes. Reject num_keys values that are too large to fit into the SCSI command. This will become important when pr_read_keys() is exposed to untrusted userspace via an ioctl. Signed-off-by: Stefan Hajnoczi --- drivers/scsi/sd.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 0252d3f6bed17..d65646f35f453 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -1974,9 +1974,18 @@ static int sd_pr_read_keys(struct block_device *bdev= , struct pr_keys *keys_info) { int result, i, data_offset, num_copy_keys; u32 num_keys =3D keys_info->num_keys; - int data_len =3D num_keys * 8 + 8; + int data_len; u8 *data; =20 + /* + * Each reservation key takes 8 bytes and there is an 8-byte header + * before the reservation key list. The total size must fit into the + * 16-bit ALLOCATION LENGTH field. + */ + if (num_keys > (65536 - 8) / 8) + return -EINVAL; + + data_len =3D num_keys * 8 + 8; data =3D kzalloc(data_len, GFP_KERNEL); if (!data) return -ENOMEM; --=20 2.52.0