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 06830C5DF70 for ; Sat, 15 Aug 2026 17:31:09 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C48F810E222; Sat, 15 Aug 2026 17:31:07 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="SOMxxLTe"; dkim-atps=neutral Received: from mail-oo1-f49.google.com (mail-oo1-f49.google.com [209.85.161.49]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4438510E0F8 for ; Sat, 15 Aug 2026 17:31:04 +0000 (UTC) Received: by mail-oo1-f49.google.com with SMTP id 006d021491bc7-6acc88b9c5fso1073608eaf.2 for ; Sat, 15 Aug 2026 10:31:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1786815063; x=1787419863; darn=lists.freedesktop.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :content-type:mime-version:subject:date:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=9eBdlB/mya9lLTAlc5ou5OAcHoUR69Q2TaK5PmrsA1I=; b=SOMxxLTeAMzIo81JaFV+EJVHEnRL5u5dKQ0z+aACqFp54k5kmQMvZk/rL3fit1v9K+ zsyzgNaoxZzT8qkqfPUgI569MAHKKr2LuYungVW2Ogh//7+OPqiJznaryoJCimhTQnqC iBGqqvs6vLPEvKlAL7uVI31Y5XCsenc5tqXJW2z8rYt4ziPD6lLMp0RMHWZTiiPHNZLS irhTx4PyR00cnq1E/0SVSEW9bwF3WCq3S78P1uR503sRa1D1Vxm7iJyCRevOAluSbsFA +If24aaSxIdjVp6ryq9AXGGqWCHc5GnTPabyQ/cpP/8g2LZDaj4UqTlCphOQqOw24lKX 4SZg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1786815063; x=1787419863; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :content-type:mime-version:subject:date:from:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=9eBdlB/mya9lLTAlc5ou5OAcHoUR69Q2TaK5PmrsA1I=; b=SbbvZAq7v4wavy8k20vGIV/AwxPlqzcXEBgdARHanSsLvq8b+RtaW4xFXgHI9lwOvG psnYAmaViJ84x/7hI/lmdLF3XWHBu38AMJMfJFpws2iYc0ZVOWuPXsknR0d77m2f20Pk Jo/xolrE/USExHcSUX5lwQ26O24C1ESDJp6I/G3gtTvXASfvhrnoNXFzk1oVzo2pjogL LZuBcLafXcbX2qOm/eFMxIxUHZI/XMjE5dFh0M+nk8HOCOtVuC6d2Ag26gazNsc+LYAB svuk4CjPeOwam4nPis2BtY4puUY2CDDBFuvvb/SIMiMApG3K2UD+IWp1Y2KrEklTFMLo uUjA== X-Gm-Message-State: AOJu0YxXaaQeUnjM5TRHHxQNKJ4utuSJ+7niInhLlraCE9gd3DX8C8Em 4w7arElnw9ucfh28v+duv2nN+kI720HB2sp4tqi2StmMPlyv6yl8wI2DDgC3E5Ev X-Gm-Gg: AR+sD119flEu4V3lF5jjRlRegvJgcFqbap3p25q5HOa2tWBM4HbZH8I8LBvCvBqzc5Q pDGozSGHRvAkTd3viCTI3Ll2K6aHKeIAsO4VCgh5QQ81Rg4zxV3MB2gOXi9jlf/zy+W8lLnYWq9 Iq2c9XqIdZ1UUNUWp7JUfHlcy1haaWKfjgLU7DjwHLr/WY1s6vMwZNzX5cZKhnHRj1tb1BiVZX2 gRfVnUKw7nxg8t/6Fq/SBEJZyz0I1rlI7a19FXS/vixLw7MTS2+U7E2wcXzixo535js1IUIr44/ 69ZjNNulR8M5ccAFsxLkg8VqFqPXZxI4i13uChEgWn2W7RvX4MSWM+9UnsgIF6nrieLqhgvJx6o wFu1mPbfUunvX1HB9TPUzBQiA0TRls6Mb9WBNxHDLvO14aaAaLF7GI+IdUIclyqoHhguBhuM5g5 qCLWvIhj3leb6odJ2+/dzom2h6ZS8w6muvQFhavyEWZJ2WAxzDicAQJV+BuOERJKEhv4+oOKHMs uC0++JM0Eg+6ghSbcA3HxMLXXDmir8O2xvM7B5k+Ozv4Kiqvg2L3DPdOLtrCccYspJulR1jD5n8 he2NJPFLQL7DKjirBUc= X-Received: by 2002:a05:6820:198c:b0:6ac:a45e:ff84 with SMTP id 006d021491bc7-6b0d6178f68mr12492143eaf.13.1786815063400; Sat, 15 Aug 2026 10:31:03 -0700 (PDT) Received: from [192.168.0.245] (c-98-38-17-99.hsd1.co.comcast.net. [98.38.17.99]) by smtp.googlemail.com with ESMTPSA id 46e09a7af769-7f3e86686c4sm4029328a34.23.2026.08.15.10.31.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 15 Aug 2026 10:31:02 -0700 (PDT) From: Jim Cromie Date: Sat, 15 Aug 2026 11:30:52 -0600 Subject: [PATCH 1/2] drm/nouveau: Fix NULL pointer dereferences in GETPARAM ioctl MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260815-null-fixes-v1-1-0df9dda951fb@gmail.com> References: <20260815-null-fixes-v1-0-0df9dda951fb@gmail.com> In-Reply-To: <20260815-null-fixes-v1-0-0df9dda951fb@gmail.com> To: Lyude Paul , Danilo Krummrich , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter Cc: dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org, linux-kernel@vger.kernel.org, Jim Cromie X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1786815060; l=2757; i=jim.cromie@gmail.com; s=20260203; h=from:subject:message-id; bh=MVZDrr9AdB0Vo7KRedm1n4U4GInx5SVFnRzNS1+N+Zo=; b=7UtxmLGZFzvMkY6BMZrEvXFUjeGPkc4RBlhqbpixxTBpEjYL4ZS4ob1Nv7UkTpsJorw7B6qKD 7bNy0uHZI5LBKqx/0worjGBZzN0LRsOe6yk1r3TwhKZosmYiYY6NdZF X-Developer-Key: i=jim.cromie@gmail.com; a=ed25519; pk=C6E5ODlPQo7ZBynATXH9wg7K6HxP0pIXyf4s38Qw0XE= X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" When hardware or firmware initialization fails, the graphics engine (gr) or device functions may remain NULL. Attempting to access these during the GETPARAM ioctl (e.g., NOUVEAU_GETPARAM_GRAPH_UNITS) results in a kernel NULL pointer dereference, causing a crash when userspace (GNOME/Mesa) attempts to probe the device. Add safety checks for 'gr', 'gr->func', and 'nvkm_device->func' in the ioctl handler. Return -ENODEV to signal the missing hardware state to userspace, and use NV_ERROR_ONCE to provide diagnostic proof in the kernel log without risking a console flood. RFC: These crashes may not be repeatable, they happened while I was trying to build nouveau as a builtin module, with binary blobs in the kernel image, on a laptop with an encrypted disk. Gemini tells me this won't work, so I punted. Signed-off-by: Jim Cromie --- drivers/gpu/drm/nouveau/nouveau_abi16.c | 25 +++++++++++++++++++++---- 1 file changed, 21 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/nouveau/nouveau_abi16.c b/drivers/gpu/drm/nouveau/nouveau_abi16.c index 291203121f0c..c9270c5b0fac 100644 --- a/drivers/gpu/drm/nouveau/nouveau_abi16.c +++ b/drivers/gpu/drm/nouveau/nouveau_abi16.c @@ -306,7 +306,12 @@ nouveau_abi16_ioctl_getparam(ABI16_IOCTL_ARGS) getparam->value = 1; break; case NOUVEAU_GETPARAM_GRAPH_UNITS: - getparam->value = nvkm_gr_units(gr); + if (gr && gr->func) { + getparam->value = nvkm_gr_units(gr); + } else { + NV_ERROR_ONCE(drm, "GETPARAM_GRAPH_UNITS: no gr engine or func\n"); + return -ENODEV; + } break; case NOUVEAU_GETPARAM_EXEC_PUSH_MAX: { int ib_max = getparam_dma_ib_max(device); @@ -315,11 +320,23 @@ nouveau_abi16_ioctl_getparam(ABI16_IOCTL_ARGS) break; } case NOUVEAU_GETPARAM_VRAM_BAR_SIZE: - getparam->value = nvkm_device->func->resource_size(nvkm_device, NVKM_BAR1_FB); + if (nvkm_device && nvkm_device->func && nvkm_device->func->resource_size) { + getparam->value = + nvkm_device->func->resource_size(nvkm_device, NVKM_BAR1_FB); + } else { + NV_ERROR_ONCE(drm, "GETPARAM_VRAM_BAR_SIZE: no device func\n"); + return -ENODEV; + } break; case NOUVEAU_GETPARAM_VRAM_USED: { - struct ttm_resource_manager *vram_mgr = ttm_manager_type(&drm->ttm.bdev, TTM_PL_VRAM); - getparam->value = (u64)ttm_resource_manager_usage(vram_mgr); + struct ttm_resource_manager *vram_mgr = + ttm_manager_type(&drm->ttm.bdev, TTM_PL_VRAM); + if (vram_mgr) { + getparam->value = (u64)ttm_resource_manager_usage(vram_mgr); + } else { + NV_ERROR_ONCE(drm, "GETPARAM_VRAM_USED: no vram mgr\n"); + return -ENODEV; + } break; } case NOUVEAU_GETPARAM_HAS_VMA_TILEMODE: -- 2.55.0