From patchwork Wed Mar 11 07:47:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Takashi Iwai X-Patchwork-Id: 210683 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 832E6C10F25 for ; Wed, 11 Mar 2020 07:47:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 60A53206B7 for ; Wed, 11 Mar 2020 07:47:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728255AbgCKHrJ (ORCPT ); Wed, 11 Mar 2020 03:47:09 -0400 Received: from mx2.suse.de ([195.135.220.15]:50536 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726160AbgCKHrI (ORCPT ); Wed, 11 Mar 2020 03:47:08 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 45BFEABCF; Wed, 11 Mar 2020 07:47:07 +0000 (UTC) From: Takashi Iwai To: Mauro Carvalho Chehab Cc: linux-media@vger.kernel.org Subject: [PATCH] media: rc: Use scnprintf() for avoiding potential buffer overflow Date: Wed, 11 Mar 2020 08:47:06 +0100 Message-Id: <20200311074706.8624-1-tiwai@suse.de> X-Mailer: git-send-email 2.16.4 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Since snprintf() returns the would-be-output size instead of the actual output size, the succeeding calls may go beyond the given buffer limit. Fix it by replacing with scnprintf(). Signed-off-by: Takashi Iwai --- drivers/media/rc/nuvoton-cir.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/media/rc/nuvoton-cir.c b/drivers/media/rc/nuvoton-cir.c index 5c2cd8d2d155..48a69bf23236 100644 --- a/drivers/media/rc/nuvoton-cir.c +++ b/drivers/media/rc/nuvoton-cir.c @@ -230,10 +230,10 @@ static ssize_t wakeup_data_show(struct device *dev, for (i = 0; i < fifo_len; i++) { duration = nvt_cir_wake_reg_read(nvt, CIR_WAKE_RD_FIFO_ONLY); duration = (duration & BUF_LEN_MASK) * SAMPLE_PERIOD; - buf_len += snprintf(buf + buf_len, PAGE_SIZE - buf_len, + buf_len += scnprintf(buf + buf_len, PAGE_SIZE - buf_len, "%d ", duration); } - buf_len += snprintf(buf + buf_len, PAGE_SIZE - buf_len, "\n"); + buf_len += scnprintf(buf + buf_len, PAGE_SIZE - buf_len, "\n"); spin_unlock_irqrestore(&nvt->lock, flags);