From patchwork Thu Mar 30 13:32:53 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 9654227 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 9301160350 for ; Thu, 30 Mar 2017 13:33:02 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8626B26E51 for ; Thu, 30 Mar 2017 13:33:02 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7AF1E284A5; Thu, 30 Mar 2017 13:33:02 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED, T_DKIM_INVALID autolearn=unavailable version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 47B012823E for ; Thu, 30 Mar 2017 13:33:02 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 754F06E8B0; Thu, 30 Mar 2017 13:33:01 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail-wr0-x241.google.com (mail-wr0-x241.google.com [IPv6:2a00:1450:400c:c0c::241]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8D5456E8B9 for ; Thu, 30 Mar 2017 13:33:00 +0000 (UTC) Received: by mail-wr0-x241.google.com with SMTP id k6so10947318wre.3 for ; Thu, 30 Mar 2017 06:33:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=from:to:cc:subject:date:message-id; bh=CJMgUR3fjaD+SbJ3vRw+dxY6S0GPoU+SqNZ1ME0CE+c=; b=GLNBajKs0Qd2KnfaHw7avQsrk7DmCo1d3x+gX7XNcEKxPAR/btA3Gce4qoaItS523b yIy78EbA0n4fJFkTjP5OeUdjJ1a/uIo6Dk6iwzY0TVe5mRrCGIGZAUPmuQqvV/u3cdj5 Dd+1iuivvVT6fcVFCcdfLYmHFShfGRo2U12i4= 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=CJMgUR3fjaD+SbJ3vRw+dxY6S0GPoU+SqNZ1ME0CE+c=; b=DQtzzAQRl5dn6FIQQJM7bfMQujVfMLjYAUysaYUABRX3HZ4qasURkjBoGT98ta8G4Z wD98E0Jh01YFEab56SR790z4q0QIf6ZPmf9/SHOTfskk5BGgjbTRHm6mMYf+0OCzQJX4 Z3g6i4W1w5f5+7Dj4IGfmT1PRAgsa6cdyLPkovs7ws+JyCTD9k3RVnSt27yx4P6wX4Vt rqRtNo8we8+sKocQXOqYYJc0bV7CZurI8BHFNtUV7IccUfkePpumWuIBIq5w/V8eMaKQ 8qLdK5Hz6mQHIP0q9cE038Rl0Hv0fKvfSrdPfLpVFT95Uz4i01QuuvKRY5D9iNCRuHzV nDqQ== X-Gm-Message-State: AFeK/H0Svkj0lWFYd9CXLjlJEVuIhz8Mn5vfLRjMn8vMroL/CGtMvVynUdojOt7Nd1rVEQ== X-Received: by 10.223.128.34 with SMTP id 31mr5573109wrk.179.1490880779172; Thu, 30 Mar 2017 06:32:59 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:563a:0:c2b5:dd51:f7b6:65bb]) by smtp.gmail.com with ESMTPSA id v14sm12303941wmv.24.2017.03.30.06.32.57 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 30 Mar 2017 06:32:58 -0700 (PDT) From: Daniel Vetter To: DRI Development Subject: [PATCH] drm: Clear e after kfree in drm_mode_page_flip_ioctl Date: Thu, 30 Mar 2017 15:32:53 +0200 Message-Id: <20170330133253.29500-1-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.11.0 Cc: Daniel Vetter , Intel Graphics Development , Julia Lawall , Daniel Vetter X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP With the explicit retry loop static analyzers get confused by the control flow and believe that e could be accessed after kfree. That's not possible, but it's non-obvious, so let's clear it to NULL. We already cleared e = NULL at the top of the function, so this is all in line. Cc: Julia Lawall Reported-by: Julia Lawall Fixes: 29dc0d1de182 ("drm: Roll out acquire context for the page_flip ioctl") Cc: Harry Wentland Cc: Daniel Vetter Cc: Jani Nikula Cc: Sean Paul Signed-off-by: Daniel Vetter Reviewed-by: Harry Wentland --- drivers/gpu/drm/drm_plane.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c index ec62221d64a9..3a6de27bafed 100644 --- a/drivers/gpu/drm/drm_plane.c +++ b/drivers/gpu/drm/drm_plane.c @@ -922,6 +922,7 @@ int drm_mode_page_flip_ioctl(struct drm_device *dev, ret = drm_event_reserve_init(dev, file_priv, &e->base, &e->event.base); if (ret) { kfree(e); + e = NULL; goto out; } }