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 5E88BC433EF for ; Tue, 18 Jan 2022 08:51:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344991AbiARIv6 (ORCPT ); Tue, 18 Jan 2022 03:51:58 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:33930 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229762AbiARIv6 (ORCPT ); Tue, 18 Jan 2022 03:51:58 -0500 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 ams.source.kernel.org (Postfix) with ESMTPS id 2CA32B81223 for ; Tue, 18 Jan 2022 08:51:57 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6C64EC00446; Tue, 18 Jan 2022 08:51:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1642495916; bh=mmbRE72LXYbOsY3SOlsfgoZ86qujado8EjYBxG74Afs=; h=Subject:To:Cc:From:Date:From; b=klWbUjqDDInj6oMyl4MX/uxHgzrpONq/y3ZjTiBTio1HQ/ZVvp0sSHhrmbc9hru14 149LExtyJs3befFbALUSl0jCCxTL1Y3neYEkQJW8pzhUz6Qr2pzykBu/lh16f+nKxO LkTicCqnNEbZg/ObN9d26TG0egrab2x1eQ2mgiNg= Subject: FAILED: patch "[PATCH] firmware: qemu_fw_cfg: fix kobject leak in probe error path" failed to apply to 4.9-stable tree To: johan@kernel.org, gregkh@linuxfoundation.org, somlo@cmu.edu Cc: From: Date: Tue, 18 Jan 2022 09:51:45 +0100 Message-ID: <16424959052209@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 47a1db8e797da01a1309bf42e0c0d771d4e4d4f3 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Wed, 1 Dec 2021 14:25:26 +0100 Subject: [PATCH] firmware: qemu_fw_cfg: fix kobject leak in probe error path An initialised kobject must be freed using kobject_put() to avoid leaking associated resources (e.g. the object name). Commit fe3c60684377 ("firmware: Fix a reference count leak.") "fixed" the leak in the first error path of the file registration helper but left the second one unchanged. This "fix" would however result in a NULL pointer dereference due to the release function also removing the never added entry from the fw_cfg_entry_cache list. This has now been addressed. Fix the remaining kobject leak by restoring the common error path and adding the missing kobject_put(). Fixes: 75f3e8e47f38 ("firmware: introduce sysfs driver for QEMU's fw_cfg device") Cc: stable@vger.kernel.org # 4.6 Cc: Gabriel Somlo Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20211201132528.30025-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman diff --git a/drivers/firmware/qemu_fw_cfg.c b/drivers/firmware/qemu_fw_cfg.c index a9c64ebfc49a..ccb7ed62452f 100644 --- a/drivers/firmware/qemu_fw_cfg.c +++ b/drivers/firmware/qemu_fw_cfg.c @@ -603,15 +603,13 @@ static int fw_cfg_register_file(const struct fw_cfg_file *f) /* register entry under "/sys/firmware/qemu_fw_cfg/by_key/" */ err = kobject_init_and_add(&entry->kobj, &fw_cfg_sysfs_entry_ktype, fw_cfg_sel_ko, "%d", entry->select); - if (err) { - kobject_put(&entry->kobj); - return err; - } + if (err) + goto err_put_entry; /* add raw binary content access */ err = sysfs_create_bin_file(&entry->kobj, &fw_cfg_sysfs_attr_raw); if (err) - goto err_add_raw; + goto err_del_entry; /* try adding "/sys/firmware/qemu_fw_cfg/by_name/" symlink */ fw_cfg_build_symlink(fw_cfg_fname_kset, &entry->kobj, entry->name); @@ -620,9 +618,10 @@ static int fw_cfg_register_file(const struct fw_cfg_file *f) fw_cfg_sysfs_cache_enlist(entry); return 0; -err_add_raw: +err_del_entry: kobject_del(&entry->kobj); - kfree(entry); +err_put_entry: + kobject_put(&entry->kobj); return err; }