From patchwork Wed Jan 24 20:35:40 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tom Herbert X-Patchwork-Id: 865454 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=quantonium-net.20150623.gappssmtp.com header.i=@quantonium-net.20150623.gappssmtp.com header.b="GfmDCdLW"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3zRcSm4XK6z9sQm for ; Thu, 25 Jan 2018 07:38:32 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932273AbeAXUia (ORCPT ); Wed, 24 Jan 2018 15:38:30 -0500 Received: from mail-pg0-f67.google.com ([74.125.83.67]:40537 "EHLO mail-pg0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932072AbeAXUi3 (ORCPT ); Wed, 24 Jan 2018 15:38:29 -0500 Received: by mail-pg0-f67.google.com with SMTP id g16so3523880pgn.7 for ; Wed, 24 Jan 2018 12:38:29 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quantonium-net.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=KzHVWkA+v9ZHMWp75V1JgDgcOKsMH/jdR+JRRO+DrlQ=; b=GfmDCdLWj2GPGGLXt9AORb376JV3oQM0Wl0Go4vGSDit+29XE9Pl9i45X6VvHXNwHF 8wYNlKQB3jBQeldmBo9o/yXXJxsKX1QrHmBOb+T/ATfkViGTLcT/B1Xpl0FKJOt5Gj4v Y4cVeT/jHln7F8WpIQPuCrt5I40oatP1rkym9edZixgR7ZISqz4UtplCmB7eopec2Zvn LaG3EdhKXB5HTNy3hTnaLvbuOGme/lefVfNu0SCf35fos8GdN622ZxlfAC3MEhUbKthw 0I5CQN1X1048D1BdlCR3SfI57e/9fyl7cLXftL5fxE8lXFKmRN98lgfOPPMb1iFkeGSh lahg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=KzHVWkA+v9ZHMWp75V1JgDgcOKsMH/jdR+JRRO+DrlQ=; b=je+ZI0Jepme0vEa4ptO7YVYp5RLv0wne8G9yJdkhz+oYY4VV/xMUkPuIbCF88uhv5Z iY5ESyZkJo01bsmJgFN0d51+BVU9t31HfI+6mGGt4lL91A+iBH8c4vosu0k/ssmaOx3C 4A/H5c2Cw65BrWJlEh18nQXhLP3fwarM6Zuox4yUROmjfXSEOCJZ59+/CSLYAk4mGM0l elXK7prDRgFKmO2gNSUnKIkQu7SgwYzXlRS8ii+qDVkj1nqKpITJlkjEb4hBAIgIXdJp vx1ug7KZizaEvMKXj4aFC/YxQonkXWWxHp9oJiVo08/Gh2Fd0+zJIE7TXSdSmtdczwOG 2i6g== X-Gm-Message-State: AKwxytf3k45SUSum+fI+iU68VzBgbWFiuoPGfzV5pHdoCAkh7JskuatM iW5zEZMJAzMqOCiRSzISVwzHMw== X-Google-Smtp-Source: AH8x2246552nGBEsbTbcDB65WEwY7qaOs4PnkXcIGDY5WwgVfXLFj0NOj6K7ZPCvkep2hLlCiIOQTw== X-Received: by 2002:a17:902:bcc2:: with SMTP id o2-v6mr5052683pls.89.1516826309076; Wed, 24 Jan 2018 12:38:29 -0800 (PST) Received: from localhost.localdomain (c-73-162-13-107.hsd1.ca.comcast.net. [73.162.13.107]) by smtp.gmail.com with ESMTPSA id l88sm12974724pfb.149.2018.01.24.12.38.27 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 24 Jan 2018 12:38:28 -0800 (PST) From: Tom Herbert To: davem@davemloft.net Cc: netdev@vger.kernel.org, rohit@quantonium.net, jchapman@katalix.com, g.nault@alphalink.fr, Tom Herbert Subject: [PATCH v2 net-next 1/2] kcm: Only allow TCP sockets to be attached to a KCM mux Date: Wed, 24 Jan 2018 12:35:40 -0800 Message-Id: <20180124203541.3172-2-tom@quantonium.net> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20180124203541.3172-1-tom@quantonium.net> References: <20180124203541.3172-1-tom@quantonium.net> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org TCP sockets for IPv4 and IPv6 that are not listeners or in closed stated are allowed to be attached to a KCM mux. Fixes: ab7ac4eb9832 ("kcm: Kernel Connection Multiplexor module") Reported-by: syzbot+8865eaff7f9acd593945@syzkaller.appspotmail.com Signed-off-by: Tom Herbert Reviewed-by: Eric Dumazet --- net/kcm/kcmsock.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c index d4e98f20fc2a..7632797fb68e 100644 --- a/net/kcm/kcmsock.c +++ b/net/kcm/kcmsock.c @@ -1387,8 +1387,13 @@ static int kcm_attach(struct socket *sock, struct socket *csock, if (!csk) return -EINVAL; - /* We must prevent loops or risk deadlock ! */ - if (csk->sk_family == PF_KCM) + /* Only allow TCP sockets to be attached for now */ + if ((csk->sk_family != AF_INET && csk->sk_family != AF_INET6) || + csk->sk_protocol != IPPROTO_TCP) + return -EOPNOTSUPP; + + /* Don't allow listeners or closed sockets */ + if (csk->sk_state == TCP_LISTEN || csk->sk_state == TCP_CLOSE) return -EOPNOTSUPP; psock = kmem_cache_zalloc(kcm_psockp, GFP_KERNEL); From patchwork Wed Jan 24 20:35:41 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tom Herbert X-Patchwork-Id: 865455 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=quantonium-net.20150623.gappssmtp.com header.i=@quantonium-net.20150623.gappssmtp.com header.b="O6kG3znA"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3zRcSs2TSnz9sQm for ; Thu, 25 Jan 2018 07:38:37 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932302AbeAXUie (ORCPT ); Wed, 24 Jan 2018 15:38:34 -0500 Received: from mail-pg0-f66.google.com ([74.125.83.66]:42901 "EHLO mail-pg0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932072AbeAXUic (ORCPT ); Wed, 24 Jan 2018 15:38:32 -0500 Received: by mail-pg0-f66.google.com with SMTP id q67so3520387pga.9 for ; Wed, 24 Jan 2018 12:38:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quantonium-net.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=6hEO06CLXxjWtOveeRA0J/2Ul6JEw4B6NpQ57G5ibKQ=; b=O6kG3znANR2+B4UIddP7OMefdGfxARUz/gdqHaVaeYXPMmMX32GOSE9F+KRolKDAQ4 /M+KV3vn4AwN1qAJcrv8Fp4uZm074Pz8D2FGEpTKKdgKpmxJXEYUODKIw3zKUQl7dQaJ 93wKKTxBZNJzOJkExUWA09Oumqd18q4xGGx5qfLHp6lH+zM/j0CdzCViyatw4wxfqX3F L9gHwZf25dqU+iIPGPgBJU797u6acxfvamfjwcZ7/tsX6atIw2OdXeF0CU5cKU1RDmLP wM7vByAUR4FswVQzQ0idsrtsT0fW0JuIzhErc5tqYvBcO9VEBCMyq8RSDHtcwotBN1Iv VcZw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=6hEO06CLXxjWtOveeRA0J/2Ul6JEw4B6NpQ57G5ibKQ=; b=Qh0ktSKA1353z9fUJJsrx4RT1o8GZ7X2YmRP//PGdi1+V35sgYKmA+PIJG+Qf8iXwW uLJuM+lxT22r9mDcWFnUKggYgZ8RLypYdLq2JUnijxTxF3L3p6tp1cfLfNmYcKm102Ul aNynAliHCH4/T4D8n6xWCuEKm6//EnpNydj1+R5Oz14FeT+xJXQsB3kGiuQRQBdt18Po mJvVBBSaBkLsvZkZw98uTsytJmm5isQ0wpNqQOJ3l+QLR+FQJA8fCEP22roy++ca4EWh JtX6Kz9kbWRPALK6PwD+zi/kwSm95YF9CBZ/D5wa/+xAB0WW40DDodEC3w3DfnB2Fal3 OXOg== X-Gm-Message-State: AKwxytep7FMfc7+Kox+SHx5Zj7wK+BspcXXiKAaRrqwiV23ahdZ0fbN/ HT4Il77FA3wo6LgXa89G3JsZ7I9N X-Google-Smtp-Source: AH8x226L+wU1WPMCOZpQXIB4nHrNiXbWkDXdXxmzTPsrf3yOxkNqtiAtPk85QmvoP4vWuL2vtfsBkw== X-Received: by 2002:a17:902:534f:: with SMTP id b73-v6mr2034595pli.139.1516826311587; Wed, 24 Jan 2018 12:38:31 -0800 (PST) Received: from localhost.localdomain (c-73-162-13-107.hsd1.ca.comcast.net. [73.162.13.107]) by smtp.gmail.com with ESMTPSA id l88sm12974724pfb.149.2018.01.24.12.38.30 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 24 Jan 2018 12:38:30 -0800 (PST) From: Tom Herbert To: davem@davemloft.net Cc: netdev@vger.kernel.org, rohit@quantonium.net, jchapman@katalix.com, g.nault@alphalink.fr, Tom Herbert Subject: [PATCH v2 net-next 2/2] kcm: Check if sk_user_data already set in kcm_attach Date: Wed, 24 Jan 2018 12:35:41 -0800 Message-Id: <20180124203541.3172-3-tom@quantonium.net> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20180124203541.3172-1-tom@quantonium.net> References: <20180124203541.3172-1-tom@quantonium.net> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This is needed to prevent sk_user_data being overwritten. The check is done under the callback lock. This should prevent a socket from being attached twice to a KCM mux. It also prevents a socket from being attached for other use cases of sk_user_data as long as the other cases set sk_user_data under the lock. Followup work is needed to unify all the use cases of sk_user_data to use the same locking. Reported-by: syzbot+114b15f2be420a8886c3@syzkaller.appspotmail.com Fixes: ab7ac4eb9832 ("kcm: Kernel Connection Multiplexor module") Signed-off-by: Tom Herbert Reviewed-by: Eric Dumazet --- net/kcm/kcmsock.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c index 7632797fb68e..4a8d407f8902 100644 --- a/net/kcm/kcmsock.c +++ b/net/kcm/kcmsock.c @@ -1410,9 +1410,18 @@ static int kcm_attach(struct socket *sock, struct socket *csock, return err; } - sock_hold(csk); - write_lock_bh(&csk->sk_callback_lock); + + /* Check if sk_user_data is aready by KCM or someone else. + * Must be done under lock to prevent race conditions. + */ + if (csk->sk_user_data) { + write_unlock_bh(&csk->sk_callback_lock); + strp_done(&psock->strp); + kmem_cache_free(kcm_psockp, psock); + return -EALREADY; + } + psock->save_data_ready = csk->sk_data_ready; psock->save_write_space = csk->sk_write_space; psock->save_state_change = csk->sk_state_change; @@ -1420,8 +1429,11 @@ static int kcm_attach(struct socket *sock, struct socket *csock, csk->sk_data_ready = psock_data_ready; csk->sk_write_space = psock_write_space; csk->sk_state_change = psock_state_change; + write_unlock_bh(&csk->sk_callback_lock); + sock_hold(csk); + /* Finished initialization, now add the psock to the MUX. */ spin_lock_bh(&mux->lock); head = &mux->psocks;