From patchwork Mon Nov 21 22:37:17 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?b?TsOtY29sYXMgRi4gUi4gQS4gUHJhZG8=?= X-Patchwork-Id: 13051694 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 F38CAC4332F for ; Mon, 21 Nov 2022 22:37:28 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id BCFE610E341; Mon, 21 Nov 2022 22:37:27 +0000 (UTC) Received: from madras.collabora.co.uk (madras.collabora.co.uk [46.235.227.172]) by gabe.freedesktop.org (Postfix) with ESMTPS id 45C6C10E354 for ; Mon, 21 Nov 2022 22:37:23 +0000 (UTC) Received: from notapiano.myfiosgateway.com (unknown [IPv6:2600:4041:5b1a:cd00:524d:e95d:1a9c:492a]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: nfraprado) by madras.collabora.co.uk (Postfix) with ESMTPSA id 58A616602A54; Mon, 21 Nov 2022 22:37:20 +0000 (GMT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1669070241; bh=7RSaxYNrftEuEHu+tdPORhiDIvSBvNUAw0lshzAfmW0=; h=From:To:Cc:Subject:Date:From; b=RNpYOKiZRomfKJVTk6xKJYXs9oDDsrn8DyTriqLeISTgtDL4nwq7K7zJ0T3DyUZDg e1Znk/FAqixHf9VrLV4R7eLpaLCHRWjlc4oJ4HfnyPs/ePUEGk7zTZfusgmc4ny6B3 pvaiwuZzBHKwvL5esWfDrjN28hi1ZPwItelCh+N/8ql8wJ0XDfgKeAlNt9TZfotUu1 A0b3d2Tgv3YsAEWG0OcBCQopwpkgCEEgNC91DQTNaZE0P2ljBZUgxm8WoVT+JSwlNs gCnPobdNtEb8JYSO4wLySkg8gCNXOm9W+zgSZRlTRl62dEnc2qs1BNu9gMeFg/7vNM qYy4bUkmz6rag== From: =?utf-8?b?TsOtY29sYXMgRi4gUi4gQS4gUHJhZG8=?= To: Chun-Kuang Hu Subject: [PATCH] drm/mediatek: Clean dangling pointer on bind error path Date: Mon, 21 Nov 2022 17:37:17 -0500 Message-Id: <20221121223717.3429913-1-nfraprado@collabora.com> X-Mailer: git-send-email 2.38.1 MIME-Version: 1.0 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: =?utf-8?b?TsOtY29sYXMgRi4gUi4gQS4gUHJhZG8=?= , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, "Nancy . Lin" , linux-mediatek@lists.infradead.org, Matthias Brugger , kernel@collabora.com, linux-arm-kernel@lists.infradead.org, AngeloGioacchino Del Regno Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" mtk_drm_bind() can fail, in which case drm_dev_put() is called, destroying the drm_device object. However a pointer to it was still being held in the private object, and that pointer would be passed along to DRM in mtk_drm_sys_prepare() if a suspend were triggered at that point, resulting in a panic. Clean the pointer when destroying the object in the error path to prevent this from happening. Signed-off-by: Nícolas F. R. A. Prado --- drivers/gpu/drm/mediatek/mtk_drm_drv.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c index 39a42dc8fb85..a21ff1b3258c 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c @@ -514,6 +514,7 @@ static int mtk_drm_bind(struct device *dev) err_deinit: mtk_drm_kms_deinit(drm); err_free: + private->drm = NULL; drm_dev_put(drm); return ret; }