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 736DBC6FD1E for ; Fri, 10 Mar 2023 22:16:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231837AbjCJWQk (ORCPT ); Fri, 10 Mar 2023 17:16:40 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46510 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231634AbjCJWQT (ORCPT ); Fri, 10 Mar 2023 17:16:19 -0500 Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7C1CC144178; Fri, 10 Mar 2023 14:16:17 -0800 (PST) Received: from pps.filterd (m0246617.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 32ALi0Op014913; Fri, 10 Mar 2023 22:15:57 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=corp-2022-7-12; bh=uBlMdD7r1eIccZBQ2mT5dGoN2iebPaDSiGe5Dh8nfOk=; b=P6djNuwI1m0QuxDQh9o5r3DwvqepmKuomSKRQm64ltkMc878UZ5ABtAJNDapkNE8Me3U CfHNsC9xb0XmM4ErbJKx6svibahFvBlRruzYftD64Vd/UuacKnFSLRPlHTRSKtszFhMH j+nCoHlJLuED5OjGlSrW+foi9EfPvOsyKb0YVfmfYQgeA5OtxdtP/1xHtdX3BLJtvpcH 1E0RtDEO7jKIU/PUo0LUrpBcbUlyNjj+c3d3ALyF9z394q0FJUywjmRJXN/nj7MU1wjE 7oUqOs5iEZyk9GSh25Hsuc9kefC3Og6udJ6zXNuU7CK5py3fslelFvJlyedu+0S73U23 9A== Received: from phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta01.appoci.oracle.com [138.1.114.2]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3p416wxc8v-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 10 Mar 2023 22:15:56 +0000 Received: from pps.filterd (phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (8.17.1.5/8.17.1.5) with ESMTP id 32ALelle031645; Fri, 10 Mar 2023 22:15:56 GMT Received: from pps.reinject (localhost [127.0.0.1]) by phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTPS id 3p6feqs9sr-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 10 Mar 2023 22:15:56 +0000 Received: from phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 32AMFrOx028711; Fri, 10 Mar 2023 22:15:55 GMT Received: from ca-dev112.us.oracle.com (ca-dev112.us.oracle.com [10.129.136.47]) by phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTP id 3p6feqs9nh-3; Fri, 10 Mar 2023 22:15:55 +0000 From: Anjali Kulkarni To: davem@davemloft.net Cc: edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, zbr@ioremap.net, brauner@kernel.org, johannes@sipsolutions.net, ecree.xilinx@gmail.com, leon@kernel.org, keescook@chromium.org, socketcan@hartkopp.net, petrm@nvidia.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, anjali.k.kulkarni@oracle.com Subject: [PATCH v1 2/5] connector/cn_proc: Add filtering to fix some bugs Date: Fri, 10 Mar 2023 14:15:44 -0800 Message-Id: <20230310221547.3656194-3-anjali.k.kulkarni@oracle.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230310221547.3656194-1-anjali.k.kulkarni@oracle.com> References: <20230310221547.3656194-1-anjali.k.kulkarni@oracle.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.942,Hydra:6.0.573,FMLib:17.11.170.22 definitions=2023-03-10_10,2023-03-10_01,2023-02-09_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 spamscore=0 bulkscore=0 mlxlogscore=999 suspectscore=0 malwarescore=0 mlxscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2212070000 definitions=main-2303100177 X-Proofpoint-GUID: mjOixkxXrRr-Kyi4NpG8a4ICe-efpavc X-Proofpoint-ORIG-GUID: mjOixkxXrRr-Kyi4NpG8a4ICe-efpavc Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org One bug is if there are more than one listeners for the proc connector messages, and one of them deregisters for listening using PROC_CN_MCAST_IGNORE, they will still get all proc connector messages, as long as there is another listener. Another issue is if one client calls PROC_CN_MCAST_LISTEN, and another one calls PROC_CN_MCAST_IGNORE, then both will end up not getting any messages. This patch adds filtering and drops packet if client has sent PROC_CN_MCAST_IGNORE. This data is stored in the client socket's sk_user_data. In addition, we only increment or decrement proc_event_num_listeners once per client. This fixes the above issues. Signed-off-by: Anjali Kulkarni --- drivers/connector/cn_proc.c | 53 ++++++++++++++++++++++++++++------- drivers/connector/connector.c | 12 +++++--- drivers/w1/w1_netlink.c | 6 ++-- include/linux/connector.h | 6 +++- include/uapi/linux/cn_proc.h | 43 ++++++++++++++++------------ net/netlink/af_netlink.c | 10 +++++-- 6 files changed, 93 insertions(+), 37 deletions(-) diff --git a/drivers/connector/cn_proc.c b/drivers/connector/cn_proc.c index ccac1c453080..84f38d2bd4b9 100644 --- a/drivers/connector/cn_proc.c +++ b/drivers/connector/cn_proc.c @@ -48,6 +48,21 @@ static DEFINE_PER_CPU(struct local_event, local_event) = { .lock = INIT_LOCAL_LOCK(lock), }; +static int cn_filter(struct sock *dsk, struct sk_buff *skb, void *data) +{ + enum proc_cn_mcast_op mc_op; + + if (!dsk) + return 0; + + mc_op = ((struct proc_input *)(dsk->sk_user_data))->mcast_op; + + if (mc_op == PROC_CN_MCAST_IGNORE) + return 1; + + return 0; +} + static inline void send_msg(struct cn_msg *msg) { local_lock(&local_event.lock); @@ -61,7 +76,8 @@ static inline void send_msg(struct cn_msg *msg) * * If cn_netlink_send() fails, the data is not sent. */ - cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_NOWAIT); + cn_netlink_send_mult(msg, msg->len, 0, CN_IDX_PROC, GFP_NOWAIT, + cn_filter, NULL); local_unlock(&local_event.lock); } @@ -346,11 +362,9 @@ static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack) static void cn_proc_mcast_ctl(struct cn_msg *msg, struct netlink_skb_parms *nsp) { - enum proc_cn_mcast_op *mc_op = NULL; - int err = 0; - - if (msg->len != sizeof(*mc_op)) - return; + enum proc_cn_mcast_op mc_op = 0, prev_mc_op = 0; + int err = 0, initial = 0; + struct sock *sk = NULL; /* * Events are reported with respect to the initial pid @@ -367,13 +381,32 @@ static void cn_proc_mcast_ctl(struct cn_msg *msg, goto out; } - mc_op = (enum proc_cn_mcast_op *)msg->data; - switch (*mc_op) { + if (msg->len == sizeof(mc_op)) + mc_op = *((enum proc_cn_mcast_op *)msg->data); + else + return; + + if (nsp->sk) { + sk = nsp->sk; + if (sk->sk_user_data == NULL) { + sk->sk_user_data = kzalloc(sizeof(struct proc_input), + GFP_KERNEL); + initial = 1; + } else { + prev_mc_op = + ((struct proc_input *)(sk->sk_user_data))->mcast_op; + } + ((struct proc_input *)(sk->sk_user_data))->mcast_op = mc_op; + } + + switch (mc_op) { case PROC_CN_MCAST_LISTEN: - atomic_inc(&proc_event_num_listeners); + if (initial || (prev_mc_op != PROC_CN_MCAST_LISTEN)) + atomic_inc(&proc_event_num_listeners); break; case PROC_CN_MCAST_IGNORE: - atomic_dec(&proc_event_num_listeners); + if (!initial && (prev_mc_op != PROC_CN_MCAST_IGNORE)) + atomic_dec(&proc_event_num_listeners); break; default: err = EINVAL; diff --git a/drivers/connector/connector.c b/drivers/connector/connector.c index 48ec7ce6ecac..1b7851b1aa0f 100644 --- a/drivers/connector/connector.c +++ b/drivers/connector/connector.c @@ -59,7 +59,9 @@ static int cn_already_initialized; * both, or if both are zero then the group is looked up and sent there. */ int cn_netlink_send_mult(struct cn_msg *msg, u16 len, u32 portid, u32 __group, - gfp_t gfp_mask) + gfp_t gfp_mask, + int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data), + void *filter_data) { struct cn_callback_entry *__cbq; unsigned int size; @@ -110,8 +112,9 @@ int cn_netlink_send_mult(struct cn_msg *msg, u16 len, u32 portid, u32 __group, NETLINK_CB(skb).dst_group = group; if (group) - return netlink_broadcast(dev->nls, skb, portid, group, - gfp_mask); + return netlink_broadcast_filtered(dev->nls, skb, portid, group, + gfp_mask, filter, + (void *)filter_data); return netlink_unicast(dev->nls, skb, portid, !gfpflags_allow_blocking(gfp_mask)); } @@ -121,7 +124,8 @@ EXPORT_SYMBOL_GPL(cn_netlink_send_mult); int cn_netlink_send(struct cn_msg *msg, u32 portid, u32 __group, gfp_t gfp_mask) { - return cn_netlink_send_mult(msg, msg->len, portid, __group, gfp_mask); + return cn_netlink_send_mult(msg, msg->len, portid, __group, gfp_mask, + NULL, NULL); } EXPORT_SYMBOL_GPL(cn_netlink_send); diff --git a/drivers/w1/w1_netlink.c b/drivers/w1/w1_netlink.c index db110cc442b1..691978cddab7 100644 --- a/drivers/w1/w1_netlink.c +++ b/drivers/w1/w1_netlink.c @@ -65,7 +65,8 @@ static void w1_unref_block(struct w1_cb_block *block) u16 len = w1_reply_len(block); if (len) { cn_netlink_send_mult(block->first_cn, len, - block->portid, 0, GFP_KERNEL); + block->portid, 0, + GFP_KERNEL, NULL, NULL); } kfree(block); } @@ -83,7 +84,8 @@ static void w1_reply_make_space(struct w1_cb_block *block, u16 space) { u16 len = w1_reply_len(block); if (len + space >= block->maxlen) { - cn_netlink_send_mult(block->first_cn, len, block->portid, 0, GFP_KERNEL); + cn_netlink_send_mult(block->first_cn, len, block->portid, + 0, GFP_KERNEL, NULL, NULL); block->first_cn->len = 0; block->cn = NULL; block->msg = NULL; diff --git a/include/linux/connector.h b/include/linux/connector.h index 487350bb19c3..1336a5e7dd2f 100644 --- a/include/linux/connector.h +++ b/include/linux/connector.h @@ -96,7 +96,11 @@ void cn_del_callback(const struct cb_id *id); * * If there are no listeners for given group %-ESRCH can be returned. */ -int cn_netlink_send_mult(struct cn_msg *msg, u16 len, u32 portid, u32 group, gfp_t gfp_mask); +int cn_netlink_send_mult(struct cn_msg *msg, u16 len, u32 portid, + u32 group, gfp_t gfp_mask, + int (*filter)(struct sock *dsk, struct sk_buff *skb, + void *data), + void *filter_data); /** * cn_netlink_send - Sends message to the specified groups. diff --git a/include/uapi/linux/cn_proc.h b/include/uapi/linux/cn_proc.h index db210625cee8..6a06fb424313 100644 --- a/include/uapi/linux/cn_proc.h +++ b/include/uapi/linux/cn_proc.h @@ -30,6 +30,30 @@ enum proc_cn_mcast_op { PROC_CN_MCAST_IGNORE = 2 }; +enum proc_cn_event { + /* Use successive bits so the enums can be used to record + * sets of events as well + */ + PROC_EVENT_NONE = 0x00000000, + PROC_EVENT_FORK = 0x00000001, + PROC_EVENT_EXEC = 0x00000002, + PROC_EVENT_UID = 0x00000004, + PROC_EVENT_GID = 0x00000040, + PROC_EVENT_SID = 0x00000080, + PROC_EVENT_PTRACE = 0x00000100, + PROC_EVENT_COMM = 0x00000200, + /* "next" should be 0x00000400 */ + /* "last" is the last process event: exit, + * while "next to last" is coredumping event + */ + PROC_EVENT_COREDUMP = 0x40000000, + PROC_EVENT_EXIT = 0x80000000 +}; + +struct proc_input { + enum proc_cn_mcast_op mcast_op; +}; + /* * From the user's point of view, the process * ID is the thread group ID and thread ID is the internal @@ -44,24 +68,7 @@ enum proc_cn_mcast_op { */ struct proc_event { - enum what { - /* Use successive bits so the enums can be used to record - * sets of events as well - */ - PROC_EVENT_NONE = 0x00000000, - PROC_EVENT_FORK = 0x00000001, - PROC_EVENT_EXEC = 0x00000002, - PROC_EVENT_UID = 0x00000004, - PROC_EVENT_GID = 0x00000040, - PROC_EVENT_SID = 0x00000080, - PROC_EVENT_PTRACE = 0x00000100, - PROC_EVENT_COMM = 0x00000200, - /* "next" should be 0x00000400 */ - /* "last" is the last process event: exit, - * while "next to last" is coredumping event */ - PROC_EVENT_COREDUMP = 0x40000000, - PROC_EVENT_EXIT = 0x80000000 - } what; + enum proc_cn_event what; __u32 cpu; __u64 __attribute__((aligned(8))) timestamp_ns; /* Number of nano seconds since system boot */ diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 003c7e6ec9be..b311375b8c4c 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -63,6 +63,7 @@ #include #include #include +#include #include #include @@ -767,9 +768,14 @@ static int netlink_release(struct socket *sock) /* must not acquire netlink_table_lock in any way again before unbind * and notifying genetlink is done as otherwise it might deadlock */ - if (nlk->netlink_unbind) { + if (nlk->netlink_unbind && nlk->groups) { int i; - + if (sk->sk_protocol == NETLINK_CONNECTOR) { + if (test_bit(CN_IDX_PROC - 1, nlk->groups)) { + kfree(sk->sk_user_data); + sk->sk_user_data = NULL; + } + } for (i = 0; i < nlk->ngroups; i++) if (test_bit(i, nlk->groups)) nlk->netlink_unbind(sock_net(sk), i + 1); -- 2.31.1