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 X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 8562CC07E9A for ; Wed, 14 Jul 2021 14:54:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 71137608FE for ; Wed, 14 Jul 2021 14:54:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239546AbhGNO50 (ORCPT ); Wed, 14 Jul 2021 10:57:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38430 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231797AbhGNO5Y (ORCPT ); Wed, 14 Jul 2021 10:57:24 -0400 Received: from mail-pf1-x434.google.com (mail-pf1-x434.google.com [IPv6:2607:f8b0:4864:20::434]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 28783C06175F for ; Wed, 14 Jul 2021 07:54:33 -0700 (PDT) Received: by mail-pf1-x434.google.com with SMTP id 17so2263425pfz.4 for ; Wed, 14 Jul 2021 07:54:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=D6ZlnySp4n2JYKZ3BnTwy0o+3Z06IrEAN7j91AepWbA=; b=TBzn5wiz/qArllKQmKvIMY0YBIRem/ED996A0xDoCuqkK6dKUMHmbgPCBChTXLfmYy KqgT2VuoQuQ+ZaTFbFs9ZKeRHnmv+rVrolGKUCHqijanujwOslOYRaeGYX/5EDcGNdJ6 Wzmid0bJCLmRqjxyXEbOA0pO6n53fT/Zj8n4rn6wvG23GmxzYZl7lBs3MewHHDuNyzIm NhgfbWW+a1WgGgMyLfSqv6vV36RnbBRD83nJ1GKUq2UQyMJB8Z90bKmaBk4Roou70T92 WwTNGz8sM6GVGTiuumSBgxYTkofCk5F4iQxQx7xi/YNCw5XGkNQWEOclJIiA3ExpxdwV EVSw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=D6ZlnySp4n2JYKZ3BnTwy0o+3Z06IrEAN7j91AepWbA=; b=P5cuCzVlLnPEKSvaEt7UzSfI4sQXM6HzZFyKx1NZUHFoN0o1jur9Ykm8S5IswjZ8a3 JTLfTS5eAI56Sb5tYrqlQ5rQRr0uF2VBq1OJpNmfplejVyxU/SJA9atIHmFRepQ/8iBL gOE0agaOGiK6EuDRzBpfc45a2Fn21wB+yaN3q2dIpQA7eVriQZKSiWss4QkcIS/w6m8H Admj9v02b0DM88chGzC/T0Ym2VSZv5l9HJmRLNkguW8ppTqp4ddZwjGsDDFVXn30RnN8 hIwfDmp1FyY7gCcSiOUSDkst24oQ/TwSrOOsdZMrGtgbHGrzUK5KOmQht/OfyUOfXBSD TC1A== X-Gm-Message-State: AOAM531Z5f6kUjTlAwpMudHhS8CNag8vamGP/uLjDsYjZ0HT3ECWVXrX 03760wSNqbQwprQc1d9JPA== X-Google-Smtp-Source: ABdhPJytmXSLQnNsOiOOvEvl6ehtqWfymtV5pVH/x19S40xL1M3Ewl0Vy0jPc0IdVHs8jSu5nIZRyA== X-Received: by 2002:a63:145d:: with SMTP id 29mr10005317pgu.135.1626274472676; Wed, 14 Jul 2021 07:54:32 -0700 (PDT) Received: from vultr.guest ([107.191.53.97]) by smtp.gmail.com with ESMTPSA id e16sm3541317pgl.54.2021.07.14.07.54.30 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 14 Jul 2021 07:54:32 -0700 (PDT) From: Zheyu Ma To: christian.koenig@amd.com, ray.huang@amd.com, airlied@linux.ie, daniel@ffwll.ch Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Zheyu Ma Subject: [PATCH] drm/ttm: add a check against null pointer dereference Date: Wed, 14 Jul 2021 14:54:19 +0000 Message-Id: <1626274459-8148-1-git-send-email-zheyuma97@gmail.com> X-Mailer: git-send-email 2.7.4 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When calling ttm_range_man_fini(), 'man' may be uninitialized, which may cause a null pointer dereference bug. Fix this by checking if it is a null pointer. This log reveals it: [ 7.902580 ] BUG: kernel NULL pointer dereference, address: 0000000000000058 [ 7.905721 ] RIP: 0010:ttm_range_man_fini+0x40/0x160 [ 7.911826 ] Call Trace: [ 7.911826 ] radeon_ttm_fini+0x167/0x210 [ 7.911826 ] radeon_bo_fini+0x15/0x40 [ 7.913767 ] rs400_fini+0x55/0x80 [ 7.914358 ] radeon_device_fini+0x3c/0x140 [ 7.914358 ] radeon_driver_unload_kms+0x5c/0xe0 [ 7.914358 ] radeon_driver_load_kms+0x13a/0x200 [ 7.914358 ] ? radeon_driver_unload_kms+0xe0/0xe0 [ 7.914358 ] drm_dev_register+0x1db/0x290 [ 7.914358 ] radeon_pci_probe+0x16a/0x230 [ 7.914358 ] local_pci_probe+0x4a/0xb0 Signed-off-by: Zheyu Ma --- drivers/gpu/drm/ttm/ttm_range_manager.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/ttm/ttm_range_manager.c b/drivers/gpu/drm/ttm/ttm_range_manager.c index 03395386e8a7..f4b08a8705b3 100644 --- a/drivers/gpu/drm/ttm/ttm_range_manager.c +++ b/drivers/gpu/drm/ttm/ttm_range_manager.c @@ -181,6 +181,9 @@ int ttm_range_man_fini(struct ttm_device *bdev, struct drm_mm *mm = &rman->mm; int ret; + if (!man) + return 0; + ttm_resource_manager_set_used(man, false); ret = ttm_resource_manager_evict_all(bdev, man); -- 2.17.6