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,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 DC010C2D0DB for ; Tue, 28 Jan 2020 14:05:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B073C2468A for ; Tue, 28 Jan 2020 14:05:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580220335; bh=tGDZBRoshrw5xaOaC8h89pZSKcEEwCnkWWYwTwUhhgU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=hUpr8mtPzS4F2a9vNr5mvFkDZlKUuEY+x4A4wx187YmRYx49Zcdmus0BQdFZew7yr 4CFo9NuPxdFS1GLFQ1LkC9bQxREWzGNs65OW9TgUbAAzmC4GUQlKXMv6I0M6U6RCqs A1AAOnIh7jjxH1bya2GQC6ROw0weN5Jx1bCXGgDY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728303AbgA1OFe (ORCPT ); Tue, 28 Jan 2020 09:05:34 -0500 Received: from mail.kernel.org ([198.145.29.99]:53162 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727675AbgA1OFa (ORCPT ); Tue, 28 Jan 2020 09:05:30 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 DAC602468E; Tue, 28 Jan 2020 14:05:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580220330; bh=tGDZBRoshrw5xaOaC8h89pZSKcEEwCnkWWYwTwUhhgU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JIhFCeRAiT9PbeUHTHHTp3Mlcr1qfU7hGqmdi3RSXi/Psu4VjwfB2nLmOaQdILQ8G tXEQxVXtDoMVTBeDwrWO/z5ibe/GlCWHibgiK7T+iowyqFs6fqPqTXlJ8FzZ2259+P +/ifHnrxUkNOPHGrrpm4Z0gg/kzsm7W/rBWSYjiY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+d73682fcf7fee6982fe3@syzkaller.appspotmail.com, John Fastabend , Jakub Sitnicki , Daniel Borkmann , "David S. Miller" Subject: [PATCH 5.4 084/104] net, sk_msg: Dont check if sock is locked when tearing down psock Date: Tue, 28 Jan 2020 15:00:45 +0100 Message-Id: <20200128135828.791836526@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200128135817.238524998@linuxfoundation.org> References: <20200128135817.238524998@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: Jakub Sitnicki commit 58c8db929db1c1d785a6f5d8f8692e5dbcc35e84 upstream. As John Fastabend reports [0], psock state tear-down can happen on receive path *after* unlocking the socket, if the only other psock user, that is sockmap or sockhash, releases its psock reference before tcp_bpf_recvmsg does so: tcp_bpf_recvmsg() psock = sk_psock_get(sk) <- refcnt 2 lock_sock(sk); ... sock_map_free() <- refcnt 1 release_sock(sk) sk_psock_put() <- refcnt 0 Remove the lockdep check for socket lock in psock tear-down that got introduced in 7e81a3530206 ("bpf: Sockmap, ensure sock lock held during tear down"). [0] https://lore.kernel.org/netdev/5e25dc995d7d_74082aaee6e465b441@john-XPS-13-9370.notmuch/ Fixes: 7e81a3530206 ("bpf: Sockmap, ensure sock lock held during tear down") Reported-by: syzbot+d73682fcf7fee6982fe3@syzkaller.appspotmail.com Suggested-by: John Fastabend Signed-off-by: Jakub Sitnicki Acked-by: John Fastabend Acked-by: Daniel Borkmann Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/core/skmsg.c | 2 -- 1 file changed, 2 deletions(-) --- a/net/core/skmsg.c +++ b/net/core/skmsg.c @@ -594,8 +594,6 @@ EXPORT_SYMBOL_GPL(sk_psock_destroy); void sk_psock_drop(struct sock *sk, struct sk_psock *psock) { - sock_owned_by_me(sk); - sk_psock_cork_free(psock); sk_psock_zap_ingress(psock);