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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id F15B6C71151 for ; Fri, 13 Jun 2025 13:59:01 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B55C710E9AE; Fri, 13 Jun 2025 13:59:01 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=permerror (0-bit key) header.d=gmail.com header.i=@gmail.com header.b="Zzw1Lhtt"; dkim-atps=neutral Received: from mail-wr1-f48.google.com (mail-wr1-f48.google.com [209.85.221.48]) by gabe.freedesktop.org (Postfix) with ESMTPS id B7CCE10E1F8; Tue, 3 Jun 2025 18:04:24 +0000 (UTC) Received: by mail-wr1-f48.google.com with SMTP id ffacd0b85a97d-3a510432236so1542065f8f.0; Tue, 03 Jun 2025 11:04:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1748973863; x=1749578663; darn=lists.freedesktop.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=UUV+ii5u6eXM/9z4t0zPuEnw9506tcp6lSpVIjqTuQM=; b=Zzw1LhtttT33lgm4QKmKO60S5KXUn/O5jFw5ppRsIoeoKiJPmPKEh3EqE055Sb38ZZ cbkUTV1VneC7Vj/BDjiVzb0NRSNJDrcAS+Z/nZK9dQ9M2jMFsns8bJiQ4eb0Du0ONUod RYWS+1kWpIo3Ye4+AVHdCvkbITpkyZaJF7cEiKfGKcCwdqTZ8Y0IjU8qYqP7+IIOPc5a nUM6hLbmWWFkdk27687jPnYEch3bWAPw6mtB0xpLPGunbIMCHYUlQ92DrehcfIJwQGn5 zZSRpz3wpfZ/hyWJk2GTNbuLOBzbLucZhLBh6bIRjm9NSLg2m6DOVTJlkExFNY6G12pM PbLQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1748973863; x=1749578663; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=UUV+ii5u6eXM/9z4t0zPuEnw9506tcp6lSpVIjqTuQM=; b=hK2d0jrNdpAsJgo0D9iH8Y/ngSjAnp+nfEpUmDADcB1+4cCyI3eVqQykzbvo98UsBE luQG/jOWmLHmHosZSb77aWRFyU6Pyja+VJpxGGNavpXiMBTcF6qsoV59jHu4VaQayaeC ARdf6oe9crdJWw6exRmrZh0gZqfQan8BSmi6wBGBbVFplFD+zrwcH/GHPr83726jj+HI B6o8BfKsctVsUbfpj4LArTnD9mx4HcydkSK+0aGMdtZznZSyHw+7vMjqELsjcsAnzKGh 1Iw+imxX8gU7qDQ+7GG2Ow5SZ4qNkVghpQFCCAlTVbE/4fOUKuj0j4yXgjCSvfEH7l92 tAwA== X-Forwarded-Encrypted: i=1; AJvYcCWfWCGMI5NLqbAu2c28EA7Mltas5FUJcHuiXHTpMRuHflMyB45Xa92xUlglI5IHJ5Rp3qxfApTvB9I=@lists.freedesktop.org X-Gm-Message-State: AOJu0YzKjfokffkpTBmyoDCSbe9ZKR4cOtk5tqsyr+PyJYkYyP9LcReB MQBk7R1G7Ezos+pX4mjdfAUjaybLi8ncmA+ZW5Xn/UuA05rH1+orwdK9 X-Gm-Gg: ASbGnctbDu4kfS9X8i/UUV5BIOlEtE1hAPCHy+MMl+fRxxOWwOszq5Ssf+d8o46LtsV 2vnlor0y44j8GffhTMIKHDC1gB+pquB0weeK7RB18dN1J5Pnh0GuO1KrO8TLExlR+Vkhiykhbdq CL5WKOoC317u5Sjd81OXBJXl7oOSKi2tBsHBNc2HAOO9nVULvutAcsQHoFrTp8eidIMiGuYoMCV 1xRS3LxttDE0oYeuZtNqrUUqkKVIzfy9joYkiq1d6d16ICWIgT/SZyXGOQDwJhhgvKasnzyY1lN 0x7Yn1MZamyEhLU1+WRUkWe9UItWWepGu6AiayT4LY8kbFMH9HjpwrHPSgpIknc= X-Google-Smtp-Source: AGHT+IFWDRZ5DMF8AWYghMojAC19CnsoSoHQTSNpwtp6Jv2nP6IRBRnbRL5Y916DRs9zZwsULYr8uQ== X-Received: by 2002:a05:6000:18ad:b0:3a3:727d:10e8 with SMTP id ffacd0b85a97d-3a4fe3a6ac9mr9056440f8f.50.1748973863165; Tue, 03 Jun 2025 11:04:23 -0700 (PDT) Received: from qasdev.Home ([2a02:c7c:6696:8300:397c:823b:f900:56d9]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3a4efe5b887sm19468210f8f.18.2025.06.03.11.04.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 Jun 2025 11:04:22 -0700 (PDT) From: Qasim Ijaz To: lucas.demarchi@intel.com, thomas.hellstrom@linux.intel.com, rodrigo.vivi@intel.com, airlied@gmail.com, simona@ffwll.ch Cc: intel-xe@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH] drm/xe/hwmon: fix uninitialised access in xe_hwmon_pcode_write_power_limit Date: Tue, 3 Jun 2025 19:03:33 +0100 Message-Id: <20250603180333.32117-1-qasdev00@gmail.com> X-Mailer: git-send-email 2.39.5 MIME-Version: 1.0 Content-Type: text/plain; charset=n Content-Transfer-Encoding: 8bit X-Mailman-Approved-At: Fri, 13 Jun 2025 13:59:00 +0000 X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" val0/val1 are not initialised and are passed to xe_pcode_read(): xe_hwmon_pcode_write_power_limit() └─▶ xe_pcode_read() └─▶ pcode_mailbox_rw() └─▶ __pcode_mailbox_rw() If __pcode_mailbox_rw fails, val0/val1 could be left uninitialised leading to xe_hwmon_pcode_write_power_limit() to access them via drm_dbg. Or an uninitialised val0/val1 could be dereferenced inside __pcode_mailbox_rw. To fix zero-initialise them to avoid potential UB and propagate error on failure. Fixes: 7596d839f622 ("drm/xe/hwmon: Add support to manage power limits though mailbox") Signed-off-by: Qasim Ijaz --- drivers/gpu/drm/xe/xe_hwmon.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/xe/xe_hwmon.c b/drivers/gpu/drm/xe/xe_hwmon.c index 0d32e977537c..04acb47488a0 100644 --- a/drivers/gpu/drm/xe/xe_hwmon.c +++ b/drivers/gpu/drm/xe/xe_hwmon.c @@ -179,7 +179,7 @@ static int xe_hwmon_pcode_write_power_limit(const struct xe_hwmon *hwmon, u32 at u32 uval) { struct xe_tile *root_tile = xe_device_get_root_tile(hwmon->xe); - u32 val0, val1; + u32 val0 = 0, val1 = 0; int ret = 0; ret = xe_pcode_read(root_tile, PCODE_MBOX(PCODE_POWER_SETUP, @@ -190,9 +190,11 @@ static int xe_hwmon_pcode_write_power_limit(const struct xe_hwmon *hwmon, u32 at READ_PL_FROM_PCODE : READ_PL_FROM_FW), &val0, &val1); - if (ret) + if (ret) { drm_dbg(&hwmon->xe->drm, "read failed ch %d val0 0x%08x, val1 0x%08x, ret %d\n", channel, val0, val1, ret); + return ret; + } if (attr == PL1_HWMON_ATTR) val0 = uval; -- 2.39.5