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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6AC75C64EC4 for ; Fri, 10 Mar 2023 14:32:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232508AbjCJOcJ (ORCPT ); Fri, 10 Mar 2023 09:32:09 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57750 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232565AbjCJObf (ORCPT ); Fri, 10 Mar 2023 09:31:35 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 319DBF6C5D for ; Fri, 10 Mar 2023 06:30:48 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id B711E61745 for ; Fri, 10 Mar 2023 14:30:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CA583C433EF; Fri, 10 Mar 2023 14:30:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678458647; bh=HPD4wT44TXc6FJkK6bysETcJ69toq5QgoIfAwP/SNOM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pGCdpiRjQRDZY6TFXuq8tF0Qw/lTHNV57YV/J63szMgoF3XNJv65OrOULy9bdZQ2/ rz3DRUO2rhjW0d7lbLr6YHVbCvM6eC0Gcsodg/hzfVvVXuj9+1tNm+Z+h6S/66J27q iT6UsdROX3qM+Z+ag+WvlQgPEqiQ4fCxH3umaXmk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yuan Can , Andrzej Hajda , Ian Ray , Robert Foss , Sasha Levin Subject: [PATCH 5.4 098/357] drm/bridge: megachips: Fix error handling in i2c_register_driver() Date: Fri, 10 Mar 2023 14:36:27 +0100 Message-Id: <20230310133738.328326637@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230310133733.973883071@linuxfoundation.org> References: <20230310133733.973883071@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Yuan Can [ Upstream commit 4ecff954c370b82bce45bdca2846c5c5563e8a8a ] A problem about insmod megachips-stdpxxxx-ge-b850v3-fw.ko failed is triggered with the following log given: [ 4497.981497] Error: Driver 'stdp4028-ge-b850v3-fw' is already registered, aborting... insmod: ERROR: could not insert module megachips-stdpxxxx-ge-b850v3-fw.ko: Device or resource busy The reason is that stdpxxxx_ge_b850v3_init() returns i2c_add_driver() directly without checking its return value, if i2c_add_driver() failed, it returns without calling i2c_del_driver() on the previous i2c driver, resulting the megachips-stdpxxxx-ge-b850v3-fw can never be installed later. A simple call graph is shown as below: stdpxxxx_ge_b850v3_init() i2c_add_driver(&stdp4028_ge_b850v3_fw_driver) i2c_add_driver(&stdp2690_ge_b850v3_fw_driver) i2c_register_driver() driver_register() bus_add_driver() priv = kzalloc(...) # OOM happened # return without delete stdp4028_ge_b850v3_fw_driver Fix by calling i2c_del_driver() on stdp4028_ge_b850v3_fw_driver when i2c_add_driver() returns error. Fixes: fcfa0ddc18ed ("drm/bridge: Drivers for megachips-stdpxxxx-ge-b850v3-fw (LVDS-DP++)") Signed-off-by: Yuan Can Reviewed-by: Andrzej Hajda Tested-by: Ian Ray Signed-off-by: Robert Foss Link: https://patchwork.freedesktop.org/patch/msgid/20221108091226.114524-1-yuancan@huawei.com Signed-off-by: Sasha Levin --- drivers/gpu/drm/bridge/megachips-stdpxxxx-ge-b850v3-fw.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/bridge/megachips-stdpxxxx-ge-b850v3-fw.c b/drivers/gpu/drm/bridge/megachips-stdpxxxx-ge-b850v3-fw.c index b72f6f541d4ef..14d578fce09f9 100644 --- a/drivers/gpu/drm/bridge/megachips-stdpxxxx-ge-b850v3-fw.c +++ b/drivers/gpu/drm/bridge/megachips-stdpxxxx-ge-b850v3-fw.c @@ -426,7 +426,11 @@ static int __init stdpxxxx_ge_b850v3_init(void) if (ret) return ret; - return i2c_add_driver(&stdp2690_ge_b850v3_fw_driver); + ret = i2c_add_driver(&stdp2690_ge_b850v3_fw_driver); + if (ret) + i2c_del_driver(&stdp4028_ge_b850v3_fw_driver); + + return ret; } module_init(stdpxxxx_ge_b850v3_init); -- 2.39.2