From patchwork Wed Jan 11 20:41:36 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Robert Foss X-Patchwork-Id: 9511233 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 25A296075C for ; Wed, 11 Jan 2017 20:42:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 16BA9285FD for ; Wed, 11 Jan 2017 20:42:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0BA8F2865F; Wed, 11 Jan 2017 20:42:21 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id D432A285FD for ; Wed, 11 Jan 2017 20:42:20 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 63BEB6E9FE; Wed, 11 Jan 2017 20:42:20 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by gabe.freedesktop.org (Postfix) with ESMTPS id A426C6E9FD for ; Wed, 11 Jan 2017 20:42:18 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: robertfoss) with ESMTPSA id 0A8A3269830 From: Robert Foss To: intel-gfx@lists.freedesktop.org, Tomeu Vizoso , Maarten Lankhorst , Gustavo Padovan , Daniel Stone Date: Wed, 11 Jan 2017 15:41:36 -0500 Message-Id: <20170111204204.7727-2-robert.foss@collabora.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170111204204.7727-1-robert.foss@collabora.com> References: <20170111204204.7727-1-robert.foss@collabora.com> Subject: [Intel-gfx] [PATCH i-g-t rfc 01/29] lib/igt_debugfs: Prevent buffer overflow X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP buf array may overflow with when writing '\0' if MAX_LINE_LEN bytes are read during read(). Signed-off-by: Robert Foss --- lib/igt_debugfs.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/lib/igt_debugfs.c b/lib/igt_debugfs.c index d828687a..8b8a627a 100644 --- a/lib/igt_debugfs.c +++ b/lib/igt_debugfs.c @@ -594,13 +594,15 @@ static int read_crc(igt_pipe_crc_t *pipe_crc, igt_crc_t *out) read_len = MAX_LINE_LEN; igt_set_timeout(5, "CRC reading"); - bytes_read = read(pipe_crc->crc_fd, &buf, read_len); + bytes_read = read(pipe_crc->crc_fd, &buf, read_len - 1); igt_reset_timeout(); - if (bytes_read < 0 && errno == EAGAIN) { + if (bytes_read < 0 && errno == EAGAIN) igt_assert(pipe_crc->flags & O_NONBLOCK); + + if (bytes_read < 0) bytes_read = 0; - } + buf[bytes_read] = '\0'; if (bytes_read && !pipe_crc_init_from_string(pipe_crc, out, buf))