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=-13.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT 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 3BAAAC28CC6 for ; Sun, 2 Jun 2019 10:52:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1AF0B20673 for ; Sun, 2 Jun 2019 10:52:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726701AbfFBKwT (ORCPT ); Sun, 2 Jun 2019 06:52:19 -0400 Received: from charlotte.tuxdriver.com ([70.61.120.58]:53467 "EHLO smtp.tuxdriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726122AbfFBKwS (ORCPT ); Sun, 2 Jun 2019 06:52:18 -0400 Received: from cpe-2606-a000-111b-405a-0-0-0-162e.dyn6.twc.com ([2606:a000:111b:405a::162e] helo=localhost) by smtp.tuxdriver.com with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.63) (envelope-from ) id 1hXO5p-0006gO-VQ; Sun, 02 Jun 2019 06:52:09 -0400 Date: Sun, 2 Jun 2019 06:51:33 -0400 From: Neil Horman To: Hillf Danton Cc: linux-sctp@vger.kernel.org, netdev@vger.kernel.org, syzkaller@googlegroups.com, "David S . Miller" , linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, syzbot , Marcelo Ricardo Leitner , Xin Long , Vlad Yasevich , Eric Dumazet Subject: Re: [PATCH] net: sctp: fix memory leak in sctp_send_reset_streams Message-ID: <20190602105133.GA16948@hmswarspite.think-freely.org> References: <20190602034429.6888-1-hdanton@sina.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190602034429.6888-1-hdanton@sina.com> User-Agent: Mutt/1.11.3 (2019-02-01) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Sun, Jun 02, 2019 at 11:44:29AM +0800, Hillf Danton wrote: > > syzbot found the following crash on: > > HEAD commit: 036e3431 Merge git://git.kernel.org/pub/scm/linux/kernel/g.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=153cff12a00000 > kernel config: https://syzkaller.appspot.com/x/.config?x=8f0f63a62bb5b13c > dashboard link: https://syzkaller.appspot.com/bug?extid=6ad9c3bd0a218a2ab41d > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12561c86a00000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15b76fd8a00000 > > executing program > executing program > executing program > executing program > executing program > BUG: memory leak > unreferenced object 0xffff888123894820 (size 32): > comm "syz-executor045", pid 7267, jiffies 4294943559 (age 13.660s) > hex dump (first 32 bytes): > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > backtrace: > [<00000000c7e71c69>] kmemleak_alloc_recursive > include/linux/kmemleak.h:55 [inline] > [<00000000c7e71c69>] slab_post_alloc_hook mm/slab.h:439 [inline] > [<00000000c7e71c69>] slab_alloc mm/slab.c:3326 [inline] > [<00000000c7e71c69>] __do_kmalloc mm/slab.c:3658 [inline] > [<00000000c7e71c69>] __kmalloc+0x161/0x2c0 mm/slab.c:3669 > [<000000003250ed8e>] kmalloc_array include/linux/slab.h:670 [inline] > [<000000003250ed8e>] kcalloc include/linux/slab.h:681 [inline] > [<000000003250ed8e>] sctp_send_reset_streams+0x1ab/0x5a0 net/sctp/stream.c:302 > [<00000000cd899c6e>] sctp_setsockopt_reset_streams net/sctp/socket.c:4314 [inline] > [<00000000cd899c6e>] sctp_setsockopt net/sctp/socket.c:4765 [inline] > [<00000000cd899c6e>] sctp_setsockopt+0xc23/0x2bf0 net/sctp/socket.c:4608 > [<00000000ff3a21a2>] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3130 > [<000000009eb87ae7>] __sys_setsockopt+0x98/0x120 net/socket.c:2078 > [<00000000e0ede6ca>] __do_sys_setsockopt net/socket.c:2089 [inline] > [<00000000e0ede6ca>] __se_sys_setsockopt net/socket.c:2086 [inline] > [<00000000e0ede6ca>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2086 > [<00000000c61155f5>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:301 > [<00000000e540958c>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > > It was introduced in commit d570a59c5b5f ("sctp: only allow the out stream > reset when the stream outq is empty"), in orde to check stream outqs before > sending SCTP_STRRESET_IN_PROGRESS back to the peer of the stream. EAGAIN is > returned, however, without the nstr_list slab released, if any outq is found > to be non empty. > > Freeing the slab in question before bailing out fixes it. > > Fixes: d570a59c5b5f ("sctp: only allow the out stream reset when the stream outq is empty") > Reported-by: syzbot > Reported-by: Marcelo Ricardo Leitner > Tested-by: Marcelo Ricardo Leitner > Cc: Xin Long > Cc: Neil Horman > Cc: Vlad Yasevich > Cc: Eric Dumazet > Signed-off-by: Hillf Danton > --- > net/sctp/stream.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/net/sctp/stream.c b/net/sctp/stream.c > index 93ed078..d3e2f03 100644 > --- a/net/sctp/stream.c > +++ b/net/sctp/stream.c > @@ -310,6 +310,7 @@ int sctp_send_reset_streams(struct sctp_association *asoc, > > if (out && !sctp_stream_outq_is_empty(stream, str_nums, nstr_list)) { > retval = -EAGAIN; > + kfree(nstr_list); > goto out; > } > > -- > > Acked-by: Neil Horman