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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A9079C00144 for ; Mon, 1 Aug 2022 11:51:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231654AbiHALvR (ORCPT ); Mon, 1 Aug 2022 07:51:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35666 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230496AbiHALuI (ORCPT ); Mon, 1 Aug 2022 07:50:08 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B7B883C8D7; Mon, 1 Aug 2022 04:49:03 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id F32E46125A; Mon, 1 Aug 2022 11:49:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0FEDAC433C1; Mon, 1 Aug 2022 11:49:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1659354542; bh=56sfNEMTQcxQGZXj9gWrjrjlCxtZaq4OzlBp/NcB63s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Stko80BkiKWtLjNDbOs7NI3aNrcC9ICGZ518Eh0reWm1EzwHyqQamkounubR8Tz7u blo0d2j+rNMu5aIFExbGteToJtIMMF9h619+5N/O97vvhtz4k4wdCjkzXrwq+oJ/8U 2qln56wX5ESYjYMzNEFQBSplk6eoDNk7L7d7pj3A= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Wei Chen , Xin Long , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.4 31/34] sctp: leave the err path free in sctp_stream_init to sctp_stream_free Date: Mon, 1 Aug 2022 13:47:11 +0200 Message-Id: <20220801114129.214903256@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220801114128.025615151@linuxfoundation.org> References: <20220801114128.025615151@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Xin Long [ Upstream commit 181d8d2066c000ba0a0e6940a7ad80f1a0e68e9d ] A NULL pointer dereference was reported by Wei Chen: BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:__list_del_entry_valid+0x26/0x80 Call Trace: sctp_sched_dequeue_common+0x1c/0x90 sctp_sched_prio_dequeue+0x67/0x80 __sctp_outq_teardown+0x299/0x380 sctp_outq_free+0x15/0x20 sctp_association_free+0xc3/0x440 sctp_do_sm+0x1ca7/0x2210 sctp_assoc_bh_rcv+0x1f6/0x340 This happens when calling sctp_sendmsg without connecting to server first. In this case, a data chunk already queues up in send queue of client side when processing the INIT_ACK from server in sctp_process_init() where it calls sctp_stream_init() to alloc stream_in. If it fails to alloc stream_in all stream_out will be freed in sctp_stream_init's err path. Then in the asoc freeing it will crash when dequeuing this data chunk as stream_out is missing. As we can't free stream out before dequeuing all data from send queue, and this patch is to fix it by moving the err path stream_out/in freeing in sctp_stream_init() to sctp_stream_free() which is eventually called when freeing the asoc in sctp_association_free(). This fix also makes the code in sctp_process_init() more clear. Note that in sctp_association_init() when it fails in sctp_stream_init(), sctp_association_free() will not be called, and in that case it should go to 'stream_free' err path to free stream instead of 'fail_init'. Fixes: 5bbbbe32a431 ("sctp: introduce stream scheduler foundations") Reported-by: Wei Chen Signed-off-by: Xin Long Link: https://lore.kernel.org/r/831a3dc100c4908ff76e5bcc363be97f2778bc0b.1658787066.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/sctp/associola.c | 5 ++--- net/sctp/stream.c | 19 +++---------------- 2 files changed, 5 insertions(+), 19 deletions(-) diff --git a/net/sctp/associola.c b/net/sctp/associola.c index fb6f62264e87..f960b0e1e552 100644 --- a/net/sctp/associola.c +++ b/net/sctp/associola.c @@ -224,9 +224,8 @@ static struct sctp_association *sctp_association_init( if (!sctp_ulpq_init(&asoc->ulpq, asoc)) goto fail_init; - if (sctp_stream_init(&asoc->stream, asoc->c.sinit_num_ostreams, - 0, gfp)) - goto fail_init; + if (sctp_stream_init(&asoc->stream, asoc->c.sinit_num_ostreams, 0, gfp)) + goto stream_free; /* Initialize default path MTU. */ asoc->pathmtu = sp->pathmtu; diff --git a/net/sctp/stream.c b/net/sctp/stream.c index cd20638b6151..56762745d6e4 100644 --- a/net/sctp/stream.c +++ b/net/sctp/stream.c @@ -137,7 +137,7 @@ int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt, ret = sctp_stream_alloc_out(stream, outcnt, gfp); if (ret) - goto out_err; + return ret; for (i = 0; i < stream->outcnt; i++) SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN; @@ -145,22 +145,9 @@ int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt, handle_in: sctp_stream_interleave_init(stream); if (!incnt) - goto out; - - ret = sctp_stream_alloc_in(stream, incnt, gfp); - if (ret) - goto in_err; - - goto out; + return 0; -in_err: - sched->free(stream); - genradix_free(&stream->in); -out_err: - genradix_free(&stream->out); - stream->outcnt = 0; -out: - return ret; + return sctp_stream_alloc_in(stream, incnt, gfp); } int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid) -- 2.35.1