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=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 4ADAEC282CE for ; Mon, 22 Apr 2019 19:52:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0CE2C204EC for ; Mon, 22 Apr 2019 19:52:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555962743; bh=bI+VgawESzxGrpyBjvaq7DNGPOKI6hENJ6szL7aUcvQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=VVfHH2hGrNsXc6PFeDj3sfRuTZ90X1J2pvtI+noz9RkTkpUSIlUh1Pngb7pj7AoYQ wzF3TyX9QKVLtVVZALhAiePIfTPlMw8r6iGmF7zqmbeswzd1Q4Xve6bN55iyN39qkw ujkZ4wi9kIFnv3x1VDPXuRVnCcXQ4yXXG50bbT6w= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731075AbfDVTuY (ORCPT ); Mon, 22 Apr 2019 15:50:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:54182 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731047AbfDVTuR (ORCPT ); Mon, 22 Apr 2019 15:50:17 -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 470B0204EC; Mon, 22 Apr 2019 19:50:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555962617; bh=bI+VgawESzxGrpyBjvaq7DNGPOKI6hENJ6szL7aUcvQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ABsMdT6outftGFnS4kyQj4bj9SqPjmUUWfw+kAZjifGnucFHHbFVlrxALHQ/425iL 0Vig/LnPVo2kXQ/ZvLih7V7ybWf9oF1cUdHWFwKT2QXLXjUCfdIN6ObaamoVIcC2ar drXG1qMbcbam1TX9y0KcWoDrHk4lqvO10NjuhhPo= 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 4.4 18/21] ceph: fix use-after-free on symlink traversal Date: Mon, 22 Apr 2019 15:49:38 -0400 Message-Id: <20190422194941.13433-18-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190422194941.13433-1-sashal@kernel.org> References: <20190422194941.13433-1-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 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