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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 81BD6C33CA9 for ; Mon, 13 Jan 2020 22:36:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 57637206DA for ; Mon, 13 Jan 2020 22:36:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728746AbgAMWgh (ORCPT ); Mon, 13 Jan 2020 17:36:37 -0500 Received: from bhuna.collabora.co.uk ([46.235.227.227]:52716 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728714AbgAMWgh (ORCPT ); Mon, 13 Jan 2020 17:36:37 -0500 Received: from localhost (unknown [IPv6:2610:98:8005::27]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: krisman) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 3F6852912D6; Mon, 13 Jan 2020 22:36:34 +0000 (GMT) From: Gabriel Krisman Bertazi To: lduncan@suse.com Cc: cleech@redhat.com, martin.petersen@oracle.com, open-iscsi@googlegroups.com, linux-scsi@vger.kernel.org, kernel@collabora.com Subject: Re: [PATCH RESEND] iscsi: Don't destroy session if there are outstanding connections In-Reply-To: <20191226203148.2172200-1-krisman@collabora.com> (Gabriel Krisman Bertazi's message of "Thu, 26 Dec 2019 15:31:48 -0500") Organization: Collabora References: <20191226203148.2172200-1-krisman@collabora.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) Date: Mon, 13 Jan 2020 17:36:31 -0500 Message-ID: <85ftgjt24w.fsf@collabora.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Gabriel Krisman Bertazi writes: > From: Nick Black > > Hi, > > I thought this was already committed for some reason, until it bit me > again today. Any opposition to this one? Hi, Pinging this patch. Any oposion? >>8 > > A faulty userspace that calls destroy_session() before destroying the > connections can trigger the failure. This patch prevents the > issue by refusing to destroy the session if there are outstanding > connections. > > ------------[ cut here ]------------ > kernel BUG at mm/slub.c:306! > invalid opcode: 0000 [#1] SMP PTI > CPU: 1 PID: 1224 Comm: iscsid Not tainted 5.4.0-rc2.iscsi+ #7 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 > RIP: 0010:__slab_free+0x181/0x350 > [...] > [ 1209.686056] RSP: 0018:ffffa93d4074fae0 EFLAGS: 00010246 > [ 1209.686694] RAX: ffff934efa5ad800 RBX: 000000008010000a RCX: ffff934efa5ad800 > [ 1209.687651] RDX: ffff934efa5ad800 RSI: ffffeb4041e96b00 RDI: ffff934efd402c40 > [ 1209.688582] RBP: ffffa93d4074fb80 R08: 0000000000000001 R09: ffffffffbb5dfa26 > [ 1209.689425] R10: ffff934efa5ad800 R11: 0000000000000001 R12: ffffeb4041e96b00 > [ 1209.690285] R13: ffff934efa5ad800 R14: ffff934efd402c40 R15: 0000000000000000 > [ 1209.691213] FS: 00007f7945dfb540(0000) GS:ffff934efda80000(0000) knlGS:0000000000000000 > [ 1209.692316] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 1209.693013] CR2: 000055877fd3da80 CR3: 0000000077384000 CR4: 00000000000006e0 > [ 1209.693897] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > [ 1209.694773] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > [ 1209.695631] Call Trace: > [ 1209.695957] ? __wake_up_common_lock+0x8a/0xc0 > [ 1209.696712] iscsi_pool_free+0x26/0x40 > [ 1209.697263] iscsi_session_teardown+0x2f/0xf0 > [ 1209.698117] iscsi_sw_tcp_session_destroy+0x45/0x60 > [ 1209.698831] iscsi_if_rx+0xd88/0x14e0 > [ 1209.699370] netlink_unicast+0x16f/0x200 > [ 1209.699932] netlink_sendmsg+0x21a/0x3e0 > [ 1209.700446] sock_sendmsg+0x4f/0x60 > [ 1209.700902] ___sys_sendmsg+0x2ae/0x320 > [ 1209.701451] ? cp_new_stat+0x150/0x180 > [ 1209.701922] __sys_sendmsg+0x59/0xa0 > [ 1209.702357] do_syscall_64+0x52/0x160 > [ 1209.702812] entry_SYSCALL_64_after_hwframe+0x44/0xa9 > [ 1209.703419] RIP: 0033:0x7f7946433914 > [...] > [ 1209.706084] RSP: 002b:00007fffb99f2378 EFLAGS: 00000246 ORIG_RAX: 000000000000002e > [ 1209.706994] RAX: ffffffffffffffda RBX: 000055bc869eac20 RCX: 00007f7946433914 > [ 1209.708082] RDX: 0000000000000000 RSI: 00007fffb99f2390 RDI: 0000000000000005 > [ 1209.709120] RBP: 00007fffb99f2390 R08: 000055bc84fe9320 R09: 00007fffb99f1f07 > [ 1209.710110] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000038 > [ 1209.711085] R13: 000055bc8502306e R14: 0000000000000000 R15: 0000000000000000 > Modules linked in: > ---[ end trace a2d933ede7f730d8 ]--- > > Co-developed-by: Salman Qazi > Signed-off-by: Salman Qazi > Co-developed-by: Junho Ryu > Signed-off-by: Junho Ryu > Co-developed-by: Khazhismel Kumykov > Signed-off-by: Khazhismel Kumykov > Signed-off-by: Nick Black > Co-developed-by: Gabriel Krisman Bertazi > Signed-off-by: Gabriel Krisman Bertazi > --- > drivers/scsi/iscsi_tcp.c | 4 ++++ > drivers/scsi/scsi_transport_iscsi.c | 26 +++++++++++++++++++++++--- > 2 files changed, 27 insertions(+), 3 deletions(-) > > diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c > index 0bc63a7ab41c..b5dd1caae5e9 100644 > --- a/drivers/scsi/iscsi_tcp.c > +++ b/drivers/scsi/iscsi_tcp.c > @@ -887,6 +887,10 @@ iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max, > static void iscsi_sw_tcp_session_destroy(struct iscsi_cls_session *cls_session) > { > struct Scsi_Host *shost = iscsi_session_to_shost(cls_session); > + struct iscsi_session *session = cls_session->dd_data; > + > + if (WARN_ON_ONCE(session->leadconn)) > + return; > > iscsi_tcp_r2tpool_free(cls_session->dd_data); > iscsi_session_teardown(cls_session); > diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c > index ed8d9709b9b9..271afea654e2 100644 > --- a/drivers/scsi/scsi_transport_iscsi.c > +++ b/drivers/scsi/scsi_transport_iscsi.c > @@ -2947,6 +2947,24 @@ iscsi_set_path(struct iscsi_transport *transport, struct iscsi_uevent *ev) > return err; > } > > +static int iscsi_session_has_conns(int sid) > +{ > + struct iscsi_cls_conn *conn; > + unsigned long flags; > + int found = 0; > + > + spin_lock_irqsave(&connlock, flags); > + list_for_each_entry(conn, &connlist, conn_list) { > + if (iscsi_conn_get_sid(conn) == sid) { > + found = 1; > + break; > + } > + } > + spin_unlock_irqrestore(&connlock, flags); > + > + return found; > +} > + > static int > iscsi_set_iface_params(struct iscsi_transport *transport, > struct iscsi_uevent *ev, uint32_t len) > @@ -3524,10 +3542,12 @@ iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, uint32_t *group) > break; > case ISCSI_UEVENT_DESTROY_SESSION: > session = iscsi_session_lookup(ev->u.d_session.sid); > - if (session) > - transport->destroy_session(session); > - else > + if (!session) > err = -EINVAL; > + else if (iscsi_session_has_conns(ev->u.d_session.sid)) > + err = -EBUSY; > + else > + transport->destroy_session(session); > break; > case ISCSI_UEVENT_UNBIND_SESSION: > session = iscsi_session_lookup(ev->u.d_session.sid); > -- > 2.24.1 -- Gabriel Krisman Bertazi