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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,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 3203AC3A59F for ; Thu, 29 Aug 2019 18:23:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 090B820578 for ; Thu, 29 Aug 2019 18:23:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567103001; bh=tEh/zX/idwYlsgWRmY9MyRvVAoNdwwEcLh+B1mAIrHM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=XWdMJ/6LdzJmEKQa0T3nd8a1YadWo08TYmPsrSIAgtnJ5nJwzEalG/85J/xKTv5z8 vM2l9BaTHKCnRdRk9ldONIKebjsFH2aZB9P6phg+FRXF61fxQogzCTiqY+6e4mu2Ka R1IJOuni24cuTzjNzmtRPvvJVlwWL0qomzo3ZSFk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728786AbfH2SQ6 (ORCPT ); Thu, 29 Aug 2019 14:16:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:58800 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729875AbfH2SQt (ORCPT ); Thu, 29 Aug 2019 14:16:49 -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 C1D712341B; Thu, 29 Aug 2019 18:16:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567102608; bh=tEh/zX/idwYlsgWRmY9MyRvVAoNdwwEcLh+B1mAIrHM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nt12v1ifBqHK3b9D+DA6FJAXhiEY1VMNlTAT06wlPgSdSK3SOgMqVe23JOT3ppXIV B8TR0ws0W8+V5BVRik6CL07N+XN0I4fvFGRdEtMy73tVnlAL44K/GckkxCVvhCZKF1 9ioGSyjd3O4Av3NLuu25+ve244J123hIEhexIRf4= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Luis Henriques , Jeff Layton , Ilya Dryomov , Sasha Levin , ceph-devel@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 42/45] ceph: fix buffer free while holding i_ceph_lock in fill_inode() Date: Thu, 29 Aug 2019 14:15:42 -0400 Message-Id: <20190829181547.8280-42-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190829181547.8280-1-sashal@kernel.org> References: <20190829181547.8280-1-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: Luis Henriques [ Upstream commit af8a85a41734f37b67ba8ce69d56b685bee4ac48 ] Calling ceph_buffer_put() in fill_inode() may result in freeing the i_xattrs.blob buffer while holding the i_ceph_lock. This can be fixed by postponing the call until later, when the lock is released. The following backtrace was triggered by fstests generic/070. BUG: sleeping function called from invalid context at mm/vmalloc.c:2283 in_atomic(): 1, irqs_disabled(): 0, pid: 3852, name: kworker/0:4 6 locks held by kworker/0:4/3852: #0: 000000004270f6bb ((wq_completion)ceph-msgr){+.+.}, at: process_one_work+0x1b8/0x5f0 #1: 00000000eb420803 ((work_completion)(&(&con->work)->work)){+.+.}, at: process_one_work+0x1b8/0x5f0 #2: 00000000be1c53a4 (&s->s_mutex){+.+.}, at: dispatch+0x288/0x1476 #3: 00000000559cb958 (&mdsc->snap_rwsem){++++}, at: dispatch+0x2eb/0x1476 #4: 000000000d5ebbae (&req->r_fill_mutex){+.+.}, at: dispatch+0x2fc/0x1476 #5: 00000000a83d0514 (&(&ci->i_ceph_lock)->rlock){+.+.}, at: fill_inode.isra.0+0xf8/0xf70 CPU: 0 PID: 3852 Comm: kworker/0:4 Not tainted 5.2.0+ #441 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-prebuilt.qemu.org 04/01/2014 Workqueue: ceph-msgr ceph_con_workfn Call Trace: dump_stack+0x67/0x90 ___might_sleep.cold+0x9f/0xb1 vfree+0x4b/0x60 ceph_buffer_release+0x1b/0x60 fill_inode.isra.0+0xa9b/0xf70 ceph_fill_trace+0x13b/0xc70 ? dispatch+0x2eb/0x1476 dispatch+0x320/0x1476 ? __mutex_unlock_slowpath+0x4d/0x2a0 ceph_con_workfn+0xc97/0x2ec0 ? process_one_work+0x1b8/0x5f0 process_one_work+0x244/0x5f0 worker_thread+0x4d/0x3e0 kthread+0x105/0x140 ? process_one_work+0x5f0/0x5f0 ? kthread_park+0x90/0x90 ret_from_fork+0x3a/0x50 Signed-off-by: Luis Henriques Reviewed-by: Jeff Layton Signed-off-by: Ilya Dryomov Signed-off-by: Sasha Levin --- fs/ceph/inode.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c index 3e518c2ae2bf9..11f19432a74c4 100644 --- a/fs/ceph/inode.c +++ b/fs/ceph/inode.c @@ -742,6 +742,7 @@ static int fill_inode(struct inode *inode, struct page *locked_page, int issued, new_issued, info_caps; struct timespec64 mtime, atime, ctime; struct ceph_buffer *xattr_blob = NULL; + struct ceph_buffer *old_blob = NULL; struct ceph_string *pool_ns = NULL; struct ceph_cap *new_cap = NULL; int err = 0; @@ -878,7 +879,7 @@ static int fill_inode(struct inode *inode, struct page *locked_page, if ((ci->i_xattrs.version == 0 || !(issued & CEPH_CAP_XATTR_EXCL)) && le64_to_cpu(info->xattr_version) > ci->i_xattrs.version) { if (ci->i_xattrs.blob) - ceph_buffer_put(ci->i_xattrs.blob); + old_blob = ci->i_xattrs.blob; ci->i_xattrs.blob = xattr_blob; if (xattr_blob) memcpy(ci->i_xattrs.blob->vec.iov_base, @@ -1017,8 +1018,8 @@ static int fill_inode(struct inode *inode, struct page *locked_page, out: if (new_cap) ceph_put_cap(mdsc, new_cap); - if (xattr_blob) - ceph_buffer_put(xattr_blob); + ceph_buffer_put(old_blob); + ceph_buffer_put(xattr_blob); ceph_put_string(pool_ns); return err; } -- 2.20.1