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 X-Spam-Level: X-Spam-Status: No, score=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 19D8AC83013 for ; Tue, 1 Dec 2020 08:57:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B46BC2224C for ; Tue, 1 Dec 2020 08:57:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="o8h8wiPt" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387844AbgLAI5d (ORCPT ); Tue, 1 Dec 2020 03:57:33 -0500 Received: from mail.kernel.org ([198.145.29.99]:60746 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729248AbgLAI5Z (ORCPT ); Tue, 1 Dec 2020 03:57:25 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9B0F0221FD; Tue, 1 Dec 2020 08:56:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1606813004; bh=H06m4XaXDEk9/hbe0x+PxElOB0uisivjggLwd6N0cWk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=o8h8wiPtSks/Rs6u5JTjR1jlrhc9MOW7+QfOoXpK9+8yPJ65WvpQUxBFh/dpGRxyN zi4/RTzcRqfM0fnVGi1bNKhTYDJQyja6dFK/OPZZi0lSMWt3yNikOFvOxWJSqH6lgG TXhYxfR/J5wist+Dy1OHbR+7R38abSapa03se8UI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vamshi K Sthambamkadi , David Laight , Ard Biesheuvel , Sasha Levin Subject: [PATCH 4.9 31/42] efivarfs: revert "fix memory leak in efivarfs_create()" Date: Tue, 1 Dec 2020 09:53:29 +0100 Message-Id: <20201201084644.780505975@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201201084642.194933793@linuxfoundation.org> References: <20201201084642.194933793@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ard Biesheuvel [ Upstream commit ff04f3b6f2e27f8ae28a498416af2a8dd5072b43 ] The memory leak addressed by commit fe5186cf12e3 is a false positive: all allocations are recorded in a linked list, and freed when the filesystem is unmounted. This leads to double frees, and as reported by David, leads to crashes if SLUB is configured to self destruct when double frees occur. So drop the redundant kfree() again, and instead, mark the offending pointer variable so the allocation is ignored by kmemleak. Cc: Vamshi K Sthambamkadi Fixes: fe5186cf12e3 ("efivarfs: fix memory leak in efivarfs_create()") Reported-by: David Laight Signed-off-by: Ard Biesheuvel Signed-off-by: Sasha Levin --- fs/efivarfs/inode.c | 2 ++ fs/efivarfs/super.c | 1 - 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/efivarfs/inode.c b/fs/efivarfs/inode.c index 71fccccf317e8..5decb3e06563f 100644 --- a/fs/efivarfs/inode.c +++ b/fs/efivarfs/inode.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include @@ -104,6 +105,7 @@ static int efivarfs_create(struct inode *dir, struct dentry *dentry, var->var.VariableName[i] = '\0'; inode->i_private = var; + kmemleak_ignore(var); err = efivar_entry_add(var, &efivarfs_list); if (err) diff --git a/fs/efivarfs/super.c b/fs/efivarfs/super.c index bbf056191aaa4..b1e6acec53041 100644 --- a/fs/efivarfs/super.c +++ b/fs/efivarfs/super.c @@ -23,7 +23,6 @@ LIST_HEAD(efivarfs_list); static void efivarfs_evict_inode(struct inode *inode) { clear_inode(inode); - kfree(inode->i_private); } static const struct super_operations efivarfs_ops = { -- 2.27.0