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=-8.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_NEOMUTT 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 17F91C43381 for ; Mon, 11 Mar 2019 21:01:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C70952147C for ; Mon, 11 Mar 2019 21:01:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="JVMcRPSu" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728138AbfCKVBZ (ORCPT ); Mon, 11 Mar 2019 17:01:25 -0400 Received: from mail-qt1-f193.google.com ([209.85.160.193]:34731 "EHLO mail-qt1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727660AbfCKVBZ (ORCPT ); Mon, 11 Mar 2019 17:01:25 -0400 Received: by mail-qt1-f193.google.com with SMTP id x20so241954qto.1 for ; Mon, 11 Mar 2019 14:01:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:mime-version:content-disposition :user-agent; bh=mwG+zHmuCaPJeXwYvKvLlC56+W7HMjxMgIZATYB69fo=; b=JVMcRPSuJeWepMuYXphIy+1fyq33EmsBtAzVtLw7q3uOvbBbWioDlYI/n2zQt3HYu9 l1BMq5/iichDSb7EvAUSnBH6BoSrVmNQBX7MSf1fGfbbRriBFg+SNz4JEbQJj7ZrYB+6 uSZ1zZp849RLUcCQ13/gYUntW3HKdx9uiQyfsbknYzY70vjgdFuH8WLjsxLMSKXIUf8O Bc4IqlEeverhwdve6eaLRoBl1vwTFy+fxiXkkHDCIOqgaRaI8+9gRBONIx7n1ghDKA+p Gt8jqFn9fBvH1TvFo5JU/wU+vhBQw9z/HYKLm3XZ5y8sHv1fmUBSDttMlgm4B6lGcn6c urrQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:mime-version :content-disposition:user-agent; bh=mwG+zHmuCaPJeXwYvKvLlC56+W7HMjxMgIZATYB69fo=; b=OfBQ1fkljb58q8oTrlX7M1TIXSHmHDMmGBSnssZCo2PAQt7jx+wZLNC3rmnMV57uPL mBI/mw+gU9QR5s3k6VFFGx0a1aTlFXs1+tEMzRbEUQ1MhiQGDlMYaUEPwbOHBoOoXSUt vlfPwaQpyn9rNcl8a+6abY3O8Gqm5kPUqZykAgT+03jKUh5K0/Q6otnuC/LdmS6k7p0q mYYZDJQ8Q3SYBkLj8Fpng6Az4d6j0lgAU6tQHtuyoEWefn2QwhqJduOmH15NNuR4XC/b cVJrq/VxlLI49JRtywYIU8A/2qp+vXWF2dWIWbWyqQXLqk/pUTYfB23ZAcgwuqmu8TgJ f8yQ== X-Gm-Message-State: APjAAAVTLUMtaLohVt/iMsvg0s3kSa8yeDBQDkrdOjKmeahjZtcjvYX2 FTpwdQsjN+bIC5ey26tiLcE= X-Google-Smtp-Source: APXvYqxfvf7pB1CmraKzqEDgZYhqUMMyrzj1riqxCA/5zcIHpa4KbyAivIyMFKOUEEBDU21RbyhrEg== X-Received: by 2002:ac8:1019:: with SMTP id z25mr8562670qti.85.1552338084040; Mon, 11 Mar 2019 14:01:24 -0700 (PDT) Received: from smtp.gmail.com ([143.107.45.1]) by smtp.gmail.com with ESMTPSA id z6sm4242504qtb.67.2019.03.11.14.01.21 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Mon, 11 Mar 2019 14:01:23 -0700 (PDT) Date: Mon, 11 Mar 2019 18:01:20 -0300 From: Rodrigo Siqueira To: Maarten Lankhorst , Maxime Ripard , Sean Paul , David Airlie , Daniel Vetter , Gerd Hoffmann Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH] drm/atomic-helper: Validate pointer before dereference Message-ID: <20190311210120.fdixvenmqjoxuoqt@smtp.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: NeoMutt/20180716 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The function disable_outputs() and drm_atomic_helper_commit_modeset_enables() tries to retrieve helper_private from the target CRTC, for dereferencing some operations. However, the current implementation does not check whether helper_private is null and, if not, if it has a valid pointer to a dpms and commit functions. This commit adds pointer validations before trying to dereference the dpms and commit function. Signed-off-by: Rodrigo Siqueira --- drivers/gpu/drm/drm_atomic_helper.c | 30 ++++++++++++++++------------- 1 file changed, 17 insertions(+), 13 deletions(-) diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index 540a77a2ade9..fbeef7c461fc 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -1028,14 +1028,16 @@ disable_outputs(struct drm_device *dev, struct drm_atomic_state *old_state) /* Right function depends upon target state. */ - if (new_crtc_state->enable && funcs->prepare) - funcs->prepare(crtc); - else if (funcs->atomic_disable) - funcs->atomic_disable(crtc, old_crtc_state); - else if (funcs->disable) - funcs->disable(crtc); - else - funcs->dpms(crtc, DRM_MODE_DPMS_OFF); + if (funcs) { + if (new_crtc_state->enable && funcs->prepare) + funcs->prepare(crtc); + else if (funcs->atomic_disable) + funcs->atomic_disable(crtc, old_crtc_state); + else if (funcs->disable) + funcs->disable(crtc); + else if (funcs->dpms) + funcs->dpms(crtc, DRM_MODE_DPMS_OFF); + } if (!(dev->irq_enabled && dev->num_crtcs)) continue; @@ -1277,11 +1279,13 @@ void drm_atomic_helper_commit_modeset_enables(struct drm_device *dev, if (new_crtc_state->enable) { DRM_DEBUG_ATOMIC("enabling [CRTC:%d:%s]\n", crtc->base.id, crtc->name); - - if (funcs->atomic_enable) - funcs->atomic_enable(crtc, old_crtc_state); - else - funcs->commit(crtc); + if (funcs) { + if (funcs->atomic_enable) + funcs->atomic_enable(crtc, + old_crtc_state); + else if (funcs->atomic_enable) + funcs->commit(crtc); + } } } -- 2.21.0