From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.11]) (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 9B76D32D0FC for ; Wed, 29 Apr 2026 06:04:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777442684; cv=none; b=domlv76cha6VkyhTBAQAieBqDtVkXvhf2jI39SeEu16yN3dnbW/ezDy9mTMju1NCiF+s+rF9g+ILA0Xt8oFZ9Sgjs6VZWH50p5KD0Xl/DUsZsBAXONU39JZG2tB/Ml3928yRrc0x4t6+uHMctZJdNR1lk/YXRgH9ukE7jJpfXR4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777442684; c=relaxed/simple; bh=dfl9nC1Exc3AqWuntxQXKXMjbEeUtj6NKVJat3VsSDE=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=OsU32RfRl0FTMkYbP1qZzzQeqNtMSlFNch1B4Kdel51gME6SWY5zC/gbHz3rX2wbie6AC45lCyxN2Kpnjlj0tdAasiHjjWE39NcHWgqBVotGVoCCu9mAy3TRMs8BXr6o04Ud1K9DnasuuL4spY4wz1OlmjZe8MCWb7fVu/CuthY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=ivAxYj6v; arc=none smtp.client-ip=198.175.65.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="ivAxYj6v" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1777442684; x=1808978684; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=dfl9nC1Exc3AqWuntxQXKXMjbEeUtj6NKVJat3VsSDE=; b=ivAxYj6vfqHwJdu1aDTdUeOYWAQV7c6abH+ePNEC13I62gneTvsEGvpu IStjVNmW+UcFGazvWd8f89Iim0BF/zyStD1hxrQ7QL6Kg+GsAamHOf18z We3ouymCDswiKDaP7xC9W4ZIFnXIl1pR77dpH9+hT15GOGccY+P5dSTgW m/QTf290HphuxUG/nTjabrvj0yeRaRdNvczdI9fpWVe+/vrF/RR6NT995 ridXtnaTSJn1soxn1jNVx7ebg2Q92dzS/FYExepE/8zFeLsKN7T+qAJle L/BJyH17MzOvl/ODR5mKwWzXSfAqwbK4fef8KlPNf3pMacgAHlKeIGc0A w==; X-CSE-ConnectionGUID: P5S6JxH7Tnmdg4FrpX7FHg== X-CSE-MsgGUID: 250NhN0ATUSO19J9vZkzZA== X-IronPort-AV: E=McAfee;i="6800,10657,11770"; a="88672085" X-IronPort-AV: E=Sophos;i="6.23,205,1770624000"; d="scan'208";a="88672085" Received: from orviesa002.jf.intel.com ([10.64.159.142]) by orvoesa103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Apr 2026 23:04:44 -0700 X-CSE-ConnectionGUID: +wEHzoxDR5Kcb3xowzXUkg== X-CSE-MsgGUID: Jz6154WlSNuaWGw8DWSRew== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,205,1770624000"; d="scan'208";a="264562062" Received: from otc-chromeosbuild-8.ostc.intel.com (HELO otc-chromeosbuild-8.intel.com) ([10.54.29.153]) by orviesa002.jf.intel.com with ESMTP; 28 Apr 2026 23:04:43 -0700 From: george.d.sworo@intel.com To: maarten.lankhorst@linux.intel.com Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, George D Sworo Subject: [PATCH v2 1/2] drm/modeset_lock: add NULL check for ctx before WARN_ON Date: Tue, 28 Apr 2026 23:04:30 -0700 Message-Id: <20260429060431.1462589-2-george.d.sworo@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260429060431.1462589-1-george.d.sworo@intel.com> References: <20260429025952.1202080-1-george.d.sworo@intel.com> <20260429060431.1462589-1-george.d.sworo@intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: George D Sworo modeset_lock() and drm_modeset_drop_locks() do not validate the ctx pointer before dereferencing it in WARN_ON(ctx->contended), which can lead to a NULL pointer dereference if ctx is NULL. Add a NULL check to prevent this. Signed-off-by: George D Sworo --- drivers/gpu/drm/drm_modeset_lock.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_modeset_lock.c b/drivers/gpu/drm/drm_modeset_lock.c index beb91a13a312..2052bb9bb9e5 100644 --- a/drivers/gpu/drm/drm_modeset_lock.c +++ b/drivers/gpu/drm/drm_modeset_lock.c @@ -295,7 +295,7 @@ static inline int modeset_lock(struct drm_modeset_lock *lock, { int ret; - if (WARN_ON(ctx->contended)) + if (ctx && WARN_ON(ctx->contended)) __drm_stack_depot_print(ctx->stack_depot); if (ctx->trylock_only) { -- 2.34.1