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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 74559C10F11 for ; Wed, 24 Apr 2019 14:50:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 478A8218FC for ; Wed, 24 Apr 2019 14:50:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556117454; bh=YIQAdVhr0apGzBMl/aEiIDksJZKPdoyWLEB/z7exXT4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Q9Pua76yIVTWnDGraRuq4kD3gD0K+cOWS0plx2S7hZL82R3EnjZBgNbN7pfQ4dwj9 WUrWChQxRLI7YovNd4BczHDAzabjUcoCW7t9E+2UrQNeUMgex/al/t06F95Yv/HV6a nCJTleMr4iD9u1a1ZtIyod+QFFlCtB/L3CmwoKs8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732718AbfDXOuw (ORCPT ); Wed, 24 Apr 2019 10:50:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:49974 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732688AbfDXOur (ORCPT ); Wed, 24 Apr 2019 10:50:47 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B7789218FE; Wed, 24 Apr 2019 14:50:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556117446; bh=YIQAdVhr0apGzBMl/aEiIDksJZKPdoyWLEB/z7exXT4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fb4EAdPtLKta6QKtKAU3AXjaq7RNYvxHXqgTZk+YiUX4d/bbNMdVl7Dx07LgJ1cIi ADNPFvfFOASVfKFJbbR9fAtax6wa96PGE2itGo5Z5qNbR2gNZEoRre3S51C7jE4siZ WE3k5zm1RmgZt7RHgXPTQsMIb2h9VZTsGF+cktEw= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Al Viro , Sasha Levin , linux-mtd@lists.infradead.org Subject: [PATCH AUTOSEL 4.9 14/28] jffs2: fix use-after-free on symlink traversal Date: Wed, 24 Apr 2019 10:49:58 -0400 Message-Id: <20190424145012.30886-14-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190424145012.30886-1-sashal@kernel.org> References: <20190424145012.30886-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Al Viro [ Upstream commit 4fdcfab5b5537c21891e22e65996d4d0dd8ab4ca ] free the symlink body after the same RCU delay we have for freeing the struct inode itself, so that traversal during RCU pathwalk wouldn't step into freed memory. Signed-off-by: Al Viro Signed-off-by: Sasha Levin --- fs/jffs2/readinode.c | 5 ----- fs/jffs2/super.c | 5 ++++- 2 files changed, 4 insertions(+), 6 deletions(-) diff --git a/fs/jffs2/readinode.c b/fs/jffs2/readinode.c index 06a71dbd4833..2f236cca6095 100644 --- a/fs/jffs2/readinode.c +++ b/fs/jffs2/readinode.c @@ -1414,11 +1414,6 @@ void jffs2_do_clear_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f) jffs2_kill_fragtree(&f->fragtree, deleted?c:NULL); - if (f->target) { - kfree(f->target); - f->target = NULL; - } - fds = f->dents; while(fds) { fd = fds; diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c index 226640563df3..76aedbc97773 100644 --- a/fs/jffs2/super.c +++ b/fs/jffs2/super.c @@ -47,7 +47,10 @@ static struct inode *jffs2_alloc_inode(struct super_block *sb) static void jffs2_i_callback(struct rcu_head *head) { struct inode *inode = container_of(head, struct inode, i_rcu); - kmem_cache_free(jffs2_inode_cachep, JFFS2_INODE_INFO(inode)); + struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); + + kfree(f->target); + kmem_cache_free(jffs2_inode_cachep, f); } static void jffs2_destroy_inode(struct inode *inode) -- 2.19.1