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 <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200225230415.1975555-1-kafai@fb.com

diff --git a/include/linux/inet_diag.h b/include/linux/inet_diag.h
index 6b157ce07d74ad38180ce41a4f2f449420b3cb08..1bb94cac265f58d9c954d2a361d1c1f85a6919da 100644 (file)
--- a/include/linux/inet_diag.h
+++ b/include/linux/inet_diag.h
@@ -15,8 +15,7 @@ struct netlink_callback;
 struct inet_diag_handler {
        void            (*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);
 
        int             (*dump_one)(struct netlink_callback *cb,
                                    const struct inet_diag_req_v2 *req);
@@ -39,6 +38,11 @@ struct inet_diag_handler {
        __u16           idiag_info_size;
 };
 
+struct inet_diag_dump_data {
+       struct nlattr *req_nlas[__INET_DIAG_REQ_MAX];
+#define inet_diag_nla_bc req_nlas[INET_DIAG_REQ_BYTECODE]
+};
+
 struct inet_connection_sock;
 int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
                      struct sk_buff *skb, struct netlink_callback *cb,
@@ -46,8 +50,7 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
                      u16 nlmsg_flags, bool net_admin);
 void inet_diag_dump_icsk(struct inet_hashinfo *h, 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);
 int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo,
                            struct netlink_callback *cb,
                            const struct inet_diag_req_v2 *req);

diff --git a/include/uapi/linux/inet_diag.h b/include/uapi/linux/inet_diag.h
index a1ff345b3f3372b6195d5fca8695d8abe898ffcc..bab9a9f8da122b7b80d0b499976be439648e355c 100644 (file)
--- a/include/uapi/linux/inet_diag.h
+++ b/include/uapi/linux/inet_diag.h
@@ -64,9 +64,10 @@ struct inet_diag_req_raw {
 enum {
        INET_DIAG_REQ_NONE,
        INET_DIAG_REQ_BYTECODE,
+       __INET_DIAG_REQ_MAX,
 };
 
-#define INET_DIAG_REQ_MAX INET_DIAG_REQ_BYTECODE
+#define INET_DIAG_REQ_MAX (__INET_DIAG_REQ_MAX - 1)
 
 /* Bytecode is sequence of 4 byte commands followed by variable arguments.
  * All the commands identified by "code" are conditional jumps forward:

diff --git a/net/dccp/diag.c b/net/dccp/diag.c
index 8f1e2a653f6da2e750e1b1fadf0810a902e9fe34..8a82c5a2c5a8c9ed8885b53744ff13c2bee657d8 100644 (file)
--- a/net/dccp/diag.c
+++ b/net/dccp/diag.c
@@ -46,9 +46,9 @@ static void dccp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
 }
 
 static void dccp_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)
 {
-       inet_diag_dump_icsk(&dccp_hashinfo, skb, cb, r, bc);
+       inet_diag_dump_icsk(&dccp_hashinfo, skb, cb, r);
 }
 
 static int dccp_diag_dump_one(struct netlink_callback *cb,

diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index d2ecff3195bac9cc14adf17e3c2284f1991158e6..4bce8a477699bb31ac9619790315a62371edd291 100644 (file)
--- 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));

diff --git a/net/ipv4/raw_diag.c b/net/ipv4/raw_diag.c
index a2933eeabd917b614fc6fabe5b8ee78a367ca21b..d19cce39be1bca61f98942cb63f6d7f1f831e8a2 100644 (file)
--- a/net/ipv4/raw_diag.c
+++ b/net/ipv4/raw_diag.c
@@ -138,17 +138,21 @@ static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
 }
 
 static void raw_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)
 {
        bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
        struct raw_hashinfo *hashinfo = raw_get_hashinfo(r);
        struct net *net = sock_net(skb->sk);
+       struct inet_diag_dump_data *cb_data;
        int num, s_num, slot, s_slot;
        struct sock *sk = NULL;
+       struct nlattr *bc;
 
        if (IS_ERR(hashinfo))
                return;
 
+       cb_data = cb->data;
+       bc = cb_data->inet_diag_nla_bc;
        s_slot = cb->args[0];
        num = s_num = cb->args[1];
 

diff --git a/net/ipv4/tcp_diag.c b/net/ipv4/tcp_diag.c
index bcd3a26efff1a877670b1e21416e30fcafa267f1..75a1c985f49a267f93c01d3133326a569f8f3651 100644 (file)
--- a/net/ipv4/tcp_diag.c
+++ b/net/ipv4/tcp_diag.c
@@ -179,9 +179,9 @@ static size_t tcp_diag_get_aux_size(struct sock *sk, bool net_admin)
 }
 
 static void tcp_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)
 {
-       inet_diag_dump_icsk(&tcp_hashinfo, skb, cb, r, bc);
+       inet_diag_dump_icsk(&tcp_hashinfo, skb, cb, r);
 }
 
 static int tcp_diag_dump_one(struct netlink_callback *cb,

diff --git a/net/ipv4/udp_diag.c b/net/ipv4/udp_diag.c
index 7d65a6a5cd51ba95246c3b673d7054eb9ff99fc3..93884696abdd0707ada319816ca06aa5946b491f 100644 (file)
--- a/net/ipv4/udp_diag.c
+++ b/net/ipv4/udp_diag.c
@@ -89,12 +89,16 @@ out_nosk:
 
 static void udp_dump(struct udp_table *table, 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 net *net = sock_net(skb->sk);
+       struct inet_diag_dump_data *cb_data;
        int num, s_num, slot, s_slot;
+       struct nlattr *bc;
 
+       cb_data = cb->data;
+       bc = cb_data->inet_diag_nla_bc;
        s_slot = cb->args[0];
        num = s_num = cb->args[1];
 
@@ -142,9 +146,9 @@ done:
 }
 
 static void udp_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)
 {
-       udp_dump(&udp_table, skb, cb, r, bc);
+       udp_dump(&udp_table, skb, cb, r);
 }
 
 static int udp_diag_dump_one(struct netlink_callback *cb,
@@ -245,10 +249,9 @@ static const struct inet_diag_handler udp_diag_handler = {
 };
 
 static void udplite_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)
 {
-       udp_dump(&udplite_table, skb, cb, r, bc);
+       udp_dump(&udplite_table, skb, cb, r);
 }
 
 static int udplite_diag_dump_one(struct netlink_callback *cb,

diff --git a/net/sctp/diag.c b/net/sctp/diag.c
index bed6436cd0afcd5b3575f4378f01cc2fcaf9743b..69743a6aaf6f5f099d2f77a3a7828162d0fe3c70 100644 (file)
--- a/net/sctp/diag.c
+++ b/net/sctp/diag.c
@@ -471,7 +471,7 @@ static int sctp_diag_dump_one(struct netlink_callback *cb,
 }
 
 static void sctp_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)
 {
        u32 idiag_states = r->idiag_states;
        struct net *net = sock_net(skb->sk);