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=unavailable 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 DF480C10F11 for ; Wed, 24 Apr 2019 14:53:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A27DA218FD for ; Wed, 24 Apr 2019 14:53:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556117600; bh=mgm3x8LCKqZWOBRR7RG4dkkSKeMNPn1t2oZrreztYzE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=1hGbjsrryeJBfPMTrRqWccG7WDWZhZcYMH/WSEyBculXaPiEXyW9d236uA+myYndC j6ziG+WgUVO4U4y5bJvNq31w/1IAXpllZY9JKLbRL6GmoWNgjBg1QqxgGF2wiFuXtq H8lkDCcIrfuNQO0149y0hQlXpfApFiZa02y3vu+0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733045AbfDXOxS (ORCPT ); Wed, 24 Apr 2019 10:53:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:52848 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730765AbfDXOxO (ORCPT ); Wed, 24 Apr 2019 10:53:14 -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 32FFC218FC; Wed, 24 Apr 2019 14:53:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556117593; bh=mgm3x8LCKqZWOBRR7RG4dkkSKeMNPn1t2oZrreztYzE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sTYOXgQUDDaYus4uUs+Yyurb9swCS1NU67O23Vlw4fzv66Cl5lJ5Y804YKVW/NLf/ oPllgubygMy9+djnKizRLldSMp1IbEAsdtnx3GRfgoFSaTJ1OqVTbXgf8F3cwsnR5E 7xluATfAEp3+eKTbrbI+Hyyxn3+KjcvOoy9klfOc= 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 3.18 05/10] jffs2: fix use-after-free on symlink traversal Date: Wed, 24 Apr 2019 10:52:54 -0400 Message-Id: <20190424145259.31639-5-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190424145259.31639-1-sashal@kernel.org> References: <20190424145259.31639-1-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 386303dca382..4f390be71723 100644 --- a/fs/jffs2/readinode.c +++ b/fs/jffs2/readinode.c @@ -1429,11 +1429,6 @@ 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 0bbc31d10857..d1be5991bb66 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