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=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 AB8DBCA9EAF for ; Sun, 27 Oct 2019 21:05:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 79605214AF for ; Sun, 27 Oct 2019 21:05:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572210309; bh=A81RVS4HAZkdJfgkGLJwFqYUC30PgQ4W7edPvDik9zk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=w7cjRaUnvvBWuTS3Mz5JkV2i6a/sKmbnlSoV2GxQcss3vj2cGrc/xs3zROxDGeQsr fvoPsFbAdgPjLe0pl/JdX1OJZ4hSptGltkE3eO1WKFtQCuz3AbvZLwf3v3Wme+qJA8 zLrnwnsZ7oi+WOqGbDfo2VtMKZbp1mJHkDmxAJFw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728770AbfJ0VFH (ORCPT ); Sun, 27 Oct 2019 17:05:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:50808 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727425AbfJ0VFE (ORCPT ); Sun, 27 Oct 2019 17:05:04 -0400 Received: from localhost (100.50.158.77.rev.sfr.net [77.158.50.100]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 01831214AF; Sun, 27 Oct 2019 21:05:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572210303; bh=A81RVS4HAZkdJfgkGLJwFqYUC30PgQ4W7edPvDik9zk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MdhOHyKk7fWf2qf5/veYbFT3TaV5OIsfbSTGRprYRDyTjAR7pyCYS/Et+gkCGbWHw +82fHv1x1BOSNYvnJKd3ofZ4TwYfdpeL+RAxjB+sJJ6nXnTXQkw3iQI4pH28gb0HUS GteWBWQupJHCOg2NnQU95hRJ0nAaxZzBA37ZO7Ns= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+d44f7bbebdea49dbc84a@syzkaller.appspotmail.com, Xin Long , Marcelo Ricardo Leitner , "David S. Miller" Subject: [PATCH 4.9 19/49] sctp: change sctp_prot .no_autobind with true Date: Sun, 27 Oct 2019 22:00:57 +0100 Message-Id: <20191027203134.019988353@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191027203119.468466356@linuxfoundation.org> References: <20191027203119.468466356@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Xin Long [ Upstream commit 63dfb7938b13fa2c2fbcb45f34d065769eb09414 ] syzbot reported a memory leak: BUG: memory leak, unreferenced object 0xffff888120b3d380 (size 64): backtrace: [...] slab_alloc mm/slab.c:3319 [inline] [...] kmem_cache_alloc+0x13f/0x2c0 mm/slab.c:3483 [...] sctp_bucket_create net/sctp/socket.c:8523 [inline] [...] sctp_get_port_local+0x189/0x5a0 net/sctp/socket.c:8270 [...] sctp_do_bind+0xcc/0x200 net/sctp/socket.c:402 [...] sctp_bindx_add+0x4b/0xd0 net/sctp/socket.c:497 [...] sctp_setsockopt_bindx+0x156/0x1b0 net/sctp/socket.c:1022 [...] sctp_setsockopt net/sctp/socket.c:4641 [inline] [...] sctp_setsockopt+0xaea/0x2dc0 net/sctp/socket.c:4611 [...] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3147 [...] __sys_setsockopt+0x10f/0x220 net/socket.c:2084 [...] __do_sys_setsockopt net/socket.c:2100 [inline] It was caused by when sending msgs without binding a port, in the path: inet_sendmsg() -> inet_send_prepare() -> inet_autobind() -> .get_port/sctp_get_port(), sp->bind_hash will be set while bp->port is not. Later when binding another port by sctp_setsockopt_bindx(), a new bucket will be created as bp->port is not set. sctp's autobind is supposed to call sctp_autobind() where it does all things including setting bp->port. Since sctp_autobind() is called in sctp_sendmsg() if the sk is not yet bound, it should have skipped the auto bind. THis patch is to avoid calling inet_autobind() in inet_send_prepare() by changing sctp_prot .no_autobind with true, also remove the unused .get_port. Reported-by: syzbot+d44f7bbebdea49dbc84a@syzkaller.appspotmail.com Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sctp/socket.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -7911,7 +7911,7 @@ struct proto sctp_prot = { .backlog_rcv = sctp_backlog_rcv, .hash = sctp_hash, .unhash = sctp_unhash, - .get_port = sctp_get_port, + .no_autobind = true, .obj_size = sizeof(struct sctp_sock), .sysctl_mem = sysctl_sctp_mem, .sysctl_rmem = sysctl_sctp_rmem, @@ -7950,7 +7950,7 @@ struct proto sctpv6_prot = { .backlog_rcv = sctp_backlog_rcv, .hash = sctp_hash, .unhash = sctp_unhash, - .get_port = sctp_get_port, + .no_autobind = true, .obj_size = sizeof(struct sctp6_sock), .sysctl_mem = sysctl_sctp_mem, .sysctl_rmem = sysctl_sctp_rmem,