From patchwork Thu Jan 28 10:48:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 12053355 X-Patchwork-Delegate: kuba@kernel.org 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=unavailable 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 BDCC6C433E0 for ; Thu, 28 Jan 2021 10:50:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 76FEF60C3D for ; Thu, 28 Jan 2021 10:50:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231474AbhA1KuU (ORCPT ); Thu, 28 Jan 2021 05:50:20 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:34660 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231136AbhA1KuN (ORCPT ); Thu, 28 Jan 2021 05:50:13 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1611830922; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=G4xP0TbwxS9wJ8k/dclQcOGAebS4EKugZ0baeO2h2DA=; b=F/XNMmOLkldWnb76qQM5b845hcq2duoNADLgBFQEhGSrxrsIri2EyB5U/oEHixyO98fJJm ywMuK1egZMlmczkkoXp7kDVqrYlcIQjSMVNxVKdC6fuex4E0W1N5oSB5M2ZzBpHdL6tJtV OkHZpXlLTIscbwwae78HLZ+ZUQg7zG0= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-183-JbzL2-39NKWyF2aNsQz8zw-1; Thu, 28 Jan 2021 05:48:40 -0500 X-MC-Unique: JbzL2-39NKWyF2aNsQz8zw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 09808107ACE6; Thu, 28 Jan 2021 10:48:39 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-115-23.rdu2.redhat.com [10.10.115.23]) by smtp.corp.redhat.com (Postfix) with ESMTP id D33A060C13; Thu, 28 Jan 2021 10:48:37 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH net] rxrpc: Fix memory leak in rxrpc_lookup_local From: David Howells To: netdev@vger.kernel.org Cc: Takeshi Misawa , syzbot+305326672fed51b205f7@syzkaller.appspotmail.com, dhowells@redhat.com, linux-afs@lists.infradead.org, linux-kernel@vger.kernel.org Date: Thu, 28 Jan 2021 10:48:36 +0000 Message-ID: <161183091692.3506637.3206605651502458810.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.23 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Takeshi Misawa Commit 9ebeddef58c4 ("rxrpc: rxrpc_peer needs to hold a ref on the rxrpc_local record") Then release ref in __rxrpc_put_peer and rxrpc_put_peer_locked. struct rxrpc_peer *rxrpc_alloc_peer(struct rxrpc_local *local, gfp_t gfp) - peer->local = local; + peer->local = rxrpc_get_local(local); rxrpc_discard_prealloc also need ref release in discarding. syzbot report: BUG: memory leak unreferenced object 0xffff8881080ddc00 (size 256): comm "syz-executor339", pid 8462, jiffies 4294942238 (age 12.350s) 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 0a 00 00 00 00 c0 00 08 81 88 ff ff ................ backtrace: [<000000002b6e495f>] kmalloc include/linux/slab.h:552 [inline] [<000000002b6e495f>] kzalloc include/linux/slab.h:682 [inline] [<000000002b6e495f>] rxrpc_alloc_local net/rxrpc/local_object.c:79 [inline] [<000000002b6e495f>] rxrpc_lookup_local+0x1c1/0x760 net/rxrpc/local_object.c:244 [<000000006b43a77b>] rxrpc_bind+0x174/0x240 net/rxrpc/af_rxrpc.c:149 [<00000000fd447a55>] afs_open_socket+0xdb/0x200 fs/afs/rxrpc.c:64 [<000000007fd8867c>] afs_net_init+0x2b4/0x340 fs/afs/main.c:126 [<0000000063d80ec1>] ops_init+0x4e/0x190 net/core/net_namespace.c:152 [<00000000073c5efa>] setup_net+0xde/0x2d0 net/core/net_namespace.c:342 [<00000000a6744d5b>] copy_net_ns+0x19f/0x3e0 net/core/net_namespace.c:483 [<0000000017d3aec3>] create_new_namespaces+0x199/0x4f0 kernel/nsproxy.c:110 [<00000000186271ef>] unshare_nsproxy_namespaces+0x9b/0x120 kernel/nsproxy.c:226 [<000000002de7bac4>] ksys_unshare+0x2fe/0x5c0 kernel/fork.c:2957 [<00000000349b12ba>] __do_sys_unshare kernel/fork.c:3025 [inline] [<00000000349b12ba>] __se_sys_unshare kernel/fork.c:3023 [inline] [<00000000349b12ba>] __x64_sys_unshare+0x12/0x20 kernel/fork.c:3023 [<000000006d178ef7>] do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 [<00000000637076d4>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 9ebeddef58c4 ("rxrpc: rxrpc_peer needs to hold a ref on the rxrpc_local record") Signed-off-by: Takeshi Misawa Reported-and-tested-by: syzbot+305326672fed51b205f7@syzkaller.appspotmail.com Signed-off-by: David Howells --- net/rxrpc/call_accept.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/rxrpc/call_accept.c b/net/rxrpc/call_accept.c index 382add72c66f..1ae90fb97936 100644 --- a/net/rxrpc/call_accept.c +++ b/net/rxrpc/call_accept.c @@ -197,6 +197,7 @@ void rxrpc_discard_prealloc(struct rxrpc_sock *rx) tail = b->peer_backlog_tail; while (CIRC_CNT(head, tail, size) > 0) { struct rxrpc_peer *peer = b->peer_backlog[tail]; + rxrpc_put_local(peer->local); kfree(peer); tail = (tail + 1) & (size - 1); }