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,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 5BFF6C10F11 for ; Mon, 22 Apr 2019 19:55:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 196FD204EC for ; Mon, 22 Apr 2019 19:55:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555962901; bh=8KwuvM13c61w+jM+1mflL6W38k2dgOEfdXwlsl2kyBg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=guyxwBalt3ES1fH8Nb8abAVrM3j9XJZK99WKvNiudsMFdII9UTBH/F4PDjLHrq/oj ojUF4uHUNar0FnUNk8AzuNu+2qObtlULX4jCv5Tnw6QwOrymuVHITvFpJCBqRoCBEu 1TUB6nJtjeaavNQPIiBh4cR0A4KGXe1aQxn72GZM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731549AbfDVTzA (ORCPT ); Mon, 22 Apr 2019 15:55:00 -0400 Received: from mail.kernel.org ([198.145.29.99]:53388 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730279AbfDVTtf (ORCPT ); Mon, 22 Apr 2019 15:49:35 -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 B4A55218CD; Mon, 22 Apr 2019 19:49:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555962574; bh=8KwuvM13c61w+jM+1mflL6W38k2dgOEfdXwlsl2kyBg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=i+xh0y1l31WJhL5o0dHugnO/W88drsKpwXHrNTDblPNmJYD0rj18vNA1Onvtx6h+V s1i5U0hp60joCFbFhyGQeSCDSllDbPuwMITSRIWAuXjuDRGybAjq8EYP2GLMFO2GzY 7a7ApEV9ZIwHENvYJreRv88wwlLGQZGLohSsfcLs= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Al Viro , Ilya Dryomov , Sasha Levin , ceph-devel@vger.kernel.org Subject: [PATCH AUTOSEL 4.9 24/29] ceph: fix use-after-free on symlink traversal Date: Mon, 22 Apr 2019 15:48:43 -0400 Message-Id: <20190422194848.13049-24-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190422194848.13049-1-sashal@kernel.org> References: <20190422194848.13049-1-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 daf5cc27eed99afdea8d96e71b89ba41f5406ef6 ] 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 Reviewed-by: Jeff Layton Signed-off-by: Ilya Dryomov Signed-off-by: Sasha Levin (Microsoft) --- fs/ceph/inode.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c index 30d9d9e7057d..7a4052501866 100644 --- a/fs/ceph/inode.c +++ b/fs/ceph/inode.c @@ -523,6 +523,7 @@ static void ceph_i_callback(struct rcu_head *head) struct inode *inode = container_of(head, struct inode, i_rcu); struct ceph_inode_info *ci = ceph_inode(inode); + kfree(ci->i_symlink); kmem_cache_free(ceph_inode_cachep, ci); } @@ -554,7 +555,6 @@ void ceph_destroy_inode(struct inode *inode) ceph_put_snap_realm(mdsc, realm); } - kfree(ci->i_symlink); while ((n = rb_first(&ci->i_fragtree)) != NULL) { frag = rb_entry(n, struct ceph_inode_frag, node); rb_erase(n, &ci->i_fragtree); -- 2.19.1