From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DBCD1C00140 for ; Wed, 3 Aug 2022 01:31:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235595AbiHCBbg (ORCPT ); Tue, 2 Aug 2022 21:31:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50172 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232077AbiHCBbc (ORCPT ); Tue, 2 Aug 2022 21:31:32 -0400 Received: from mail-pj1-x1030.google.com (mail-pj1-x1030.google.com [IPv6:2607:f8b0:4864:20::1030]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EB42F558F9; Tue, 2 Aug 2022 18:31:31 -0700 (PDT) Received: by mail-pj1-x1030.google.com with SMTP id 15-20020a17090a098f00b001f305b453feso496579pjo.1; Tue, 02 Aug 2022 18:31:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc; bh=WhzCt7ZgW+LKbQwQvPVI6t++DQIekCJZ1n72lgrdeEc=; b=UfMtI5F0A32q8jVuYnhDA27lKBMWQ/8qOiUvDdoMk8XTjT+AHwCj3UumiD5U9MMxOv twpE3WsfikZnc9kUv3KbPA277def1HlItmhTT/aBAgvEG9aglUxpecD3TprBvxE0+zNN ZQaR+epa7rC0VZG5uR645bscnWRAQKSrkINuC7wpAkw8XpzGr+4H6NXOYcZUPuOP4tAX 5G3W7jNS9EHcm0v4AE7tQXPoXF9244qIdi40twGjxb3Dr46RDYMqv8smNHsMhfX1dKmB 3/GaoEfOGdC4w2y58ksD+sG7fmgTWD/1bFOAR+bTZnvc+tlAq64GJtsTn+nyWlmlmkpA CV1g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc; bh=WhzCt7ZgW+LKbQwQvPVI6t++DQIekCJZ1n72lgrdeEc=; b=vgudXcbzdt4pd4KfwOU86oc72/b+TWuz/HUpHnD3evIrcv4T2zQBO7koAauQdPRAT1 YOkGKcV+ZZSC1NPAvDOi9UDlxblS9OcMh2s68jo98K7Hamet4DvJXPBAGp+ju1k4kPXz vmyHbHNnrH7BtlY12VIFtK7Dh0eqL0Z4owqTiyQeLYS0Au5LrYgq3TH5sXOngMSimMBY fNmnE5OOn0xM4jshFkpTmGXxPr14rKg/T53AknWPuQ0k3PPQ7SPpoa/HnY4YExvFrGph MXLXEIsRTztwtfKk/PK5e8H0NNasJJuKxHJkLsDCKpsqzuV1SSJcIwz+v4OGlKUnCeut QJAA== X-Gm-Message-State: ACgBeo07w6EgTQYCNFDZ7XsFn4at3gURbrOQSJLMyqoenGQA6Dj1GPFM PsadlrGJmJSZ2vr5vtee4ZdeOIkivYvn2sO9 X-Google-Smtp-Source: AA6agR6XMDZHANAU7kA10nIDngUNjppbpRgEcfvum+qrO6pwYM9MdYrvKAGxNN2NIifQGCGyLZIi/A== X-Received: by 2002:a17:90a:a401:b0:1f2:19a0:2874 with SMTP id y1-20020a17090aa40100b001f219a02874mr2383446pjp.146.1659490291131; Tue, 02 Aug 2022 18:31:31 -0700 (PDT) Received: from sebin-inspiron.bbrouter ([103.148.20.125]) by smtp.gmail.com with ESMTPSA id x3-20020a1709027c0300b0016edb59f670sm369240pll.6.2022.08.02.18.31.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 02 Aug 2022 18:31:30 -0700 (PDT) From: Sebin Sebastian Cc: mailmesebin00@gmail.com, Alessandro Zummo , Alexandre Belloni , Michal Simek , linux-rtc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH -next] rtc: synqmp: uninitialized variable error Date: Wed, 3 Aug 2022 07:01:17 +0530 Message-Id: <20220803013117.318611-1-mailmesebin00@gmail.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org fract_tick is uninitialized and can lead to uninitialized read which can result in any arbitrary value from previous computations. If the code flow doesnt execute the `if (fract_offset > (tick_mult / RTC_FR_MAX_TICKS)) { ` block, fract_tick is left uninitialized. Initializing with zero fixes the issue. Signed-off-by: Sebin Sebastian --- drivers/rtc/rtc-zynqmp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/rtc/rtc-zynqmp.c b/drivers/rtc/rtc-zynqmp.c index 1dd389b891fe..c9b85c838ebe 100644 --- a/drivers/rtc/rtc-zynqmp.c +++ b/drivers/rtc/rtc-zynqmp.c @@ -203,7 +203,7 @@ static int xlnx_rtc_set_offset(struct device *dev, long offset) struct xlnx_rtc_dev *xrtcdev = dev_get_drvdata(dev); unsigned long long rtc_ppb = RTC_PPB; unsigned int tick_mult = do_div(rtc_ppb, xrtcdev->freq); - unsigned char fract_tick; + unsigned char fract_tick = 0; unsigned int calibval; short int max_tick; int fract_offset; -- 2.34.1