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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,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 8CD6AC04E53 for ; Wed, 15 May 2019 11:06:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5E2D6216FD for ; Wed, 15 May 2019 11:06:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557918380; bh=6jlw6kxbsl1OSxmlM7sqRC1e3PjCAuar3qYpvSLgfjM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=z1tCOZEFKZDw6UMFOUHhOdyScFD+GeFmPoKISogOyFhCWVGebGgJWbEuXTUuIQDtH F/n8gbJCYQT9dUTO1X/tP/VR1EEP60LvdswSwPe6RFIC5oAwD7T/BnnRgCr29rHTz1 NHgM6fURzPc8hJW+O043fHaDyjiVBYyjUPooJD1c= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728750AbfEOLGT (ORCPT ); Wed, 15 May 2019 07:06:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:36850 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728724AbfEOLGO (ORCPT ); Wed, 15 May 2019 07:06:14 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 04D36216FD; Wed, 15 May 2019 11:06:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557918373; bh=6jlw6kxbsl1OSxmlM7sqRC1e3PjCAuar3qYpvSLgfjM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uikffmoE/rYBHydHoLWGjGahvjHS7wt/2j4IAByh6de8fxTux+o8LZ/0bsviH7RF3 3iBfTuMoVSnEB2MbVHnKmN9G4D574k9ZoW0mW0CekqhdB1VA8Dvye65P4bRD4IfLXO iseYm8j7U+Lg9ncxbPLuAtYF95pGe9ekQkYQ/bQw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Al Viro , Jeff Layton , Ilya Dryomov , "Sasha Levin (Microsoft)" Subject: [PATCH 4.4 105/266] ceph: fix use-after-free on symlink traversal Date: Wed, 15 May 2019 12:53:32 +0200 Message-Id: <20190515090726.006075984@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190515090722.696531131@linuxfoundation.org> References: <20190515090722.696531131@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ 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 9f0d99094cc1..a663b676d566 100644 --- a/fs/ceph/inode.c +++ b/fs/ceph/inode.c @@ -474,6 +474,7 @@ 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); } @@ -505,7 +506,6 @@ 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