From patchwork Fri Jun 18 05:28:00 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiajun Cao X-Patchwork-Id: 12330191 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=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 D39BAC48BDF for ; Fri, 18 Jun 2021 05:28:32 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 2C89861351 for ; Fri, 18 Jun 2021 05:28:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2C89861351 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=fudan.edu.cn Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 869A16E84E; Fri, 18 Jun 2021 05:28:31 +0000 (UTC) Received: from zg8tmty1ljiyny4xntqumjca.icoremail.net (zg8tmty1ljiyny4xntqumjca.icoremail.net [165.227.154.27]) by gabe.freedesktop.org (Postfix) with SMTP id 4D0E46E84E for ; Fri, 18 Jun 2021 05:28:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fudan.edu.cn; s=dkim; h=Received:From:To:Cc:Subject:Date: Message-Id; bh=1u3WcLuOIJNGanaGygETlZ8Gs0rz5+WZUbX217nJS8o=; b=o qd4DHwHdcrz5/5likLjUyapj4zUeZE97fP35r3ayeiEQIErXGO391UfDxcRBvIpi n586LBomQiO3vbgQobSxxE8BeVUBjzuaLOhCkP4dRxQV5GZ9kWF0S3bfr20QQB0l ZwJitaHqC+hU3PAID23xMoWK5hZaV+5BpK27CLwnK0= Received: from ubuntu (unknown [10.177.89.109]) by app1 (Coremail) with SMTP id XAUFCgDnmDLjLsxgjEGFAA--.13317S3; Fri, 18 Jun 2021 13:28:03 +0800 (CST) From: Jiajun Cao To: Subject: [PATCH v2] drm/meson: fix potential NULL pointer exception in meson_drv_unbind() Date: Fri, 18 Jun 2021 13:28:00 +0800 Message-Id: <20210618052800.89007-1-jjcao20@fudan.edu.cn> X-Mailer: git-send-email 2.17.1 X-CM-TRANSID: XAUFCgDnmDLjLsxgjEGFAA--.13317S3 X-Coremail-Antispam: 1UD129KBjvJXoW7uw4xZw48CFWfuF4rGr48JFb_yoW8Xr1fpF 4fGryjkrWktFWUt34DAa17AFy3Jw47CFy7uF4UKwsa9r4akFyxJa4ftFWUtry5Zry0q3WS vF98KF48uFW5Ar7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBa14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26w1j6s0DM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26F4U JVW0owA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oV Cq3wAac4AC62xK8xCEY4vEwIxC4wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC 0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr 1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IE rcIFxwACI402YVCY1x02628vn2kIc2xKxwCY02Avz4vE-syl42xK82IYc2Ij64vIr41l4I 8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AK xVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r43MI8E62xC7I0kMIIYrxkI7VAKI48JMIIF0x vE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE 42xK8VAvwI8IcIk0rVWrZr1j6s0DMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2js IEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0pRcAw7UUUUU= X-CM-SenderInfo: isqsiiasuqikmw6i3vldqovvfxof0/ 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: , Cc: Xin Tan , Neil Armstrong , David Airlie , Kevin Hilman , yuanxzhang@fudan.edu.cn, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Jiajun Cao , Martin Blumenstingl , linux-amlogic@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Jerome Brunet Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Fix a potential NULL pointer exception when meson_drv_unbind() attempts to operate on the driver_data priv which may be NULL. Add a null pointer check on the priv struct to avoid the NULL pointer dereference after calling dev_get_drvdata(), just like the null pointer checks done on the struct priv in the function meson_drv_shutdown(), meson_drv_pm_suspend() and meson_drv_pm_resume(). Signed-off-by: Jiajun Cao Signed-off-by: Xin Tan --- drivers/gpu/drm/meson/meson_drv.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/meson/meson_drv.c b/drivers/gpu/drm/meson/meson_drv.c index 07fcd12dca16..f544fba8c44e 100644 --- a/drivers/gpu/drm/meson/meson_drv.c +++ b/drivers/gpu/drm/meson/meson_drv.c @@ -380,7 +380,10 @@ static int meson_drv_bind(struct device *dev) static void meson_drv_unbind(struct device *dev) { struct meson_drm *priv = dev_get_drvdata(dev); - struct drm_device *drm = priv->drm; + struct drm_device *drm; + + if (!priv) + return; if (priv->canvas) { meson_canvas_free(priv->canvas, priv->canvas_id_osd1); @@ -389,6 +392,7 @@ static void meson_drv_unbind(struct device *dev) meson_canvas_free(priv->canvas, priv->canvas_id_vd1_2); } + drm = priv->drm; drm_dev_unregister(drm); drm_kms_helper_poll_fini(drm); drm_atomic_helper_shutdown(drm);