From 0df6d32842b9a5f97a29ea90c8adc5cfac38341d Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Tue, 25 Feb 2020 15:04:15 -0800 Subject: inet_diag: Move the INET_DIAG_REQ_BYTECODE nlattr to cb->data The INET_DIAG_REQ_BYTECODE nlattr is currently re-found every time when the "dump()" is re-started. In a latter patch, it will also need to parse the new INET_DIAG_REQ_SK_BPF_STORAGES nlattr to learn the map_fds. Thus, this patch takes this chance to store the parsed nlattr in cb->data during the "start" time of a dump. By doing this, the "bc" argument also becomes unnecessary and is removed. Also, the two copies of the INET_DIAG_REQ_BYTECODE parsing-audit logic between compat/current version can be consolidated to one. Signed-off-by: Martin KaFai Lau Signed-off-by: Alexei Starovoitov Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20200225230415.1975555-1-kafai@fb.com --- net/ipv4/inet_diag.c | 117 ++++++++++++++++++++++++++++++--------------------- 1 file changed, 70 insertions(+), 47 deletions(-) (limited to 'net/ipv4/inet_diag.c') diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c index d2ecff3195ba..4bce8a477699 100644 --- a/net/ipv4/inet_diag.c +++ b/net/ipv4/inet_diag.c @@ -495,9 +495,11 @@ static int inet_diag_cmd_exact(int cmd, struct sk_buff *in_skb, if (IS_ERR(handler)) { err = PTR_ERR(handler); } else if (cmd == SOCK_DIAG_BY_FAMILY) { + struct inet_diag_dump_data empty_dump_data = {}; struct netlink_callback cb = { .nlh = nlh, .skb = in_skb, + .data = &empty_dump_data, }; err = handler->dump_one(&cb, req); } else if (cmd == SOCK_DESTROY && handler->destroy) { @@ -863,14 +865,17 @@ static void twsk_build_assert(void) void inet_diag_dump_icsk(struct inet_hashinfo *hashinfo, struct sk_buff *skb, struct netlink_callback *cb, - const struct inet_diag_req_v2 *r, struct nlattr *bc) + const struct inet_diag_req_v2 *r) { bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN); + struct inet_diag_dump_data *cb_data = cb->data; struct net *net = sock_net(skb->sk); u32 idiag_states = r->idiag_states; int i, num, s_i, s_num; + struct nlattr *bc; struct sock *sk; + bc = cb_data->inet_diag_nla_bc; if (idiag_states & TCPF_SYN_RECV) idiag_states |= TCPF_NEW_SYN_RECV; s_i = cb->args[1]; @@ -1014,15 +1019,14 @@ out: EXPORT_SYMBOL_GPL(inet_diag_dump_icsk); static int __inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, - const struct inet_diag_req_v2 *r, - struct nlattr *bc) + const struct inet_diag_req_v2 *r) { const struct inet_diag_handler *handler; int err = 0; handler = inet_diag_lock_handler(r->sdiag_protocol); if (!IS_ERR(handler)) - handler->dump(skb, cb, r, bc); + handler->dump(skb, cb, r); else err = PTR_ERR(handler); inet_diag_unlock_handler(handler); @@ -1032,13 +1036,57 @@ static int __inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, static int inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb) { - int hdrlen = sizeof(struct inet_diag_req_v2); - struct nlattr *bc = NULL; + return __inet_diag_dump(skb, cb, nlmsg_data(cb->nlh)); +} + +static int __inet_diag_dump_start(struct netlink_callback *cb, int hdrlen) +{ + const struct nlmsghdr *nlh = cb->nlh; + struct inet_diag_dump_data *cb_data; + struct sk_buff *skb = cb->skb; + struct nlattr *nla; + int rem, err; + + cb_data = kzalloc(sizeof(*cb_data), GFP_KERNEL); + if (!cb_data) + return -ENOMEM; + + nla_for_each_attr(nla, nlmsg_attrdata(nlh, hdrlen), + nlmsg_attrlen(nlh, hdrlen), rem) { + int type = nla_type(nla); + + if (type < __INET_DIAG_REQ_MAX) + cb_data->req_nlas[type] = nla; + } + + nla = cb_data->inet_diag_nla_bc; + if (nla) { + err = inet_diag_bc_audit(nla, skb); + if (err) { + kfree(cb_data); + return err; + } + } + + cb->data = cb_data; + return 0; +} + +static int inet_diag_dump_start(struct netlink_callback *cb) +{ + return __inet_diag_dump_start(cb, sizeof(struct inet_diag_req_v2)); +} + +static int inet_diag_dump_start_compat(struct netlink_callback *cb) +{ + return __inet_diag_dump_start(cb, sizeof(struct inet_diag_req)); +} - if (nlmsg_attrlen(cb->nlh, hdrlen)) - bc = nlmsg_find_attr(cb->nlh, hdrlen, INET_DIAG_REQ_BYTECODE); +static int inet_diag_dump_done(struct netlink_callback *cb) +{ + kfree(cb->data); - return __inet_diag_dump(skb, cb, nlmsg_data(cb->nlh), bc); + return 0; } static int inet_diag_type2proto(int type) @@ -1057,9 +1105,7 @@ static int inet_diag_dump_compat(struct sk_buff *skb, struct netlink_callback *cb) { struct inet_diag_req *rc = nlmsg_data(cb->nlh); - int hdrlen = sizeof(struct inet_diag_req); struct inet_diag_req_v2 req; - struct nlattr *bc = NULL; req.sdiag_family = AF_UNSPEC; /* compatibility */ req.sdiag_protocol = inet_diag_type2proto(cb->nlh->nlmsg_type); @@ -1067,10 +1113,7 @@ static int inet_diag_dump_compat(struct sk_buff *skb, req.idiag_states = rc->idiag_states; req.id = rc->id; - if (nlmsg_attrlen(cb->nlh, hdrlen)) - bc = nlmsg_find_attr(cb->nlh, hdrlen, INET_DIAG_REQ_BYTECODE); - - return __inet_diag_dump(skb, cb, &req, bc); + return __inet_diag_dump(skb, cb, &req); } static int inet_diag_get_exact_compat(struct sk_buff *in_skb, @@ -1098,22 +1141,12 @@ static int inet_diag_rcv_msg_compat(struct sk_buff *skb, struct nlmsghdr *nlh) return -EINVAL; if (nlh->nlmsg_flags & NLM_F_DUMP) { - if (nlmsg_attrlen(nlh, hdrlen)) { - struct nlattr *attr; - int err; - - attr = nlmsg_find_attr(nlh, hdrlen, - INET_DIAG_REQ_BYTECODE); - err = inet_diag_bc_audit(attr, skb); - if (err) - return err; - } - { - struct netlink_dump_control c = { - .dump = inet_diag_dump_compat, - }; - return netlink_dump_start(net->diag_nlsk, skb, nlh, &c); - } + struct netlink_dump_control c = { + .start = inet_diag_dump_start_compat, + .done = inet_diag_dump_done, + .dump = inet_diag_dump_compat, + }; + return netlink_dump_start(net->diag_nlsk, skb, nlh, &c); } return inet_diag_get_exact_compat(skb, nlh); @@ -1129,22 +1162,12 @@ static int inet_diag_handler_cmd(struct sk_buff *skb, struct nlmsghdr *h) if (h->nlmsg_type == SOCK_DIAG_BY_FAMILY && h->nlmsg_flags & NLM_F_DUMP) { - if (nlmsg_attrlen(h, hdrlen)) { - struct nlattr *attr; - int err; - - attr = nlmsg_find_attr(h, hdrlen, - INET_DIAG_REQ_BYTECODE); - err = inet_diag_bc_audit(attr, skb); - if (err) - return err; - } - { - struct netlink_dump_control c = { - .dump = inet_diag_dump, - }; - return netlink_dump_start(net->diag_nlsk, skb, h, &c); - } + struct netlink_dump_control c = { + .start = inet_diag_dump_start, + .done = inet_diag_dump_done, + .dump = inet_diag_dump, + }; + return netlink_dump_start(net->diag_nlsk, skb, h, &c); } return inet_diag_cmd_exact(h->nlmsg_type, skb, h, nlmsg_data(h)); -- cgit