From: Martin KaFai Lau <kafai@fb.com>
To: <bpf@vger.kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
David Miller <davem@davemloft.net>, <kernel-team@fb.com>,
<netdev@vger.kernel.org>
Subject: [PATCH bpf-next v2 1/4] inet_diag: Refactor inet_sk_diag_fill(), dump(), and dump_one()
Date: Tue, 25 Feb 2020 15:04:09 -0800 [thread overview]
Message-ID: <20200225230409.1975173-1-kafai@fb.com> (raw)
In-Reply-To: <20200225230402.1974723-1-kafai@fb.com>
In a latter patch, there is a need to update "cb->min_dump_alloc"
in inet_sk_diag_fill() as it learns the diffierent bpf_sk_storages
stored in a sk while dumping all sk(s) (e.g. tcp_hashinfo).
The inet_sk_diag_fill() currently does not take the "cb" as an argument.
One of the reason is inet_sk_diag_fill() is used by both dump_one()
and dump() (which belong to the "struct inet_diag_handler". The dump_one()
interface does not pass the "cb" along.
This patch is to make dump_one() pass a "cb". The "cb" is created in
inet_diag_cmd_exact(). The "nlh" and "in_skb" are stored in "cb" as
the dump() interface does. The total number of args in
inet_sk_diag_fill() is also cut from 10 to 7 and
that helps many callers to pass fewer args.
In particular,
"struct user_namespace *user_ns", "u32 pid", and "u32 seq"
can be replaced by accessing "cb->nlh" and "cb->skb".
A similar argument reduction is also made to
inet_twsk_diag_fill() and inet_req_diag_fill().
inet_csk_diag_dump() and inet_csk_diag_fill() are also removed.
They are mostly equivalent to inet_sk_diag_fill(). Their repeated
usages are very limited. Thus, inet_sk_diag_fill() is directly used
in those occasions.
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
---
include/linux/inet_diag.h | 12 ++--
net/dccp/diag.c | 5 +-
net/ipv4/inet_diag.c | 116 +++++++++++++++-----------------------
net/ipv4/raw_diag.c | 18 ++----
net/ipv4/tcp_diag.c | 4 +-
net/ipv4/udp_diag.c | 26 ++++-----
net/sctp/diag.c | 5 +-
7 files changed, 73 insertions(+), 113 deletions(-)
diff --git a/include/linux/inet_diag.h b/include/linux/inet_diag.h
index 39faaaf843e1..6b157ce07d74 100644
--- a/include/linux/inet_diag.h
+++ b/include/linux/inet_diag.h
@@ -18,8 +18,7 @@ struct inet_diag_handler {
const struct inet_diag_req_v2 *r,
struct nlattr *bc);
- int (*dump_one)(struct sk_buff *in_skb,
- const struct nlmsghdr *nlh,
+ int (*dump_one)(struct netlink_callback *cb,
const struct inet_diag_req_v2 *req);
void (*idiag_get_info)(struct sock *sk,
@@ -42,16 +41,15 @@ struct inet_diag_handler {
struct inet_connection_sock;
int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
- struct sk_buff *skb, const struct inet_diag_req_v2 *req,
- struct user_namespace *user_ns,
- u32 pid, u32 seq, u16 nlmsg_flags,
- const struct nlmsghdr *unlh, bool net_admin);
+ struct sk_buff *skb, struct netlink_callback *cb,
+ const struct inet_diag_req_v2 *req,
+ 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);
int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo,
- struct sk_buff *in_skb, const struct nlmsghdr *nlh,
+ struct netlink_callback *cb,
const struct inet_diag_req_v2 *req);
struct sock *inet_diag_find_one_icsk(struct net *net,
diff --git a/net/dccp/diag.c b/net/dccp/diag.c
index 73ef73a218ff..8f1e2a653f6d 100644
--- a/net/dccp/diag.c
+++ b/net/dccp/diag.c
@@ -51,11 +51,10 @@ static void dccp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
inet_diag_dump_icsk(&dccp_hashinfo, skb, cb, r, bc);
}
-static int dccp_diag_dump_one(struct sk_buff *in_skb,
- const struct nlmsghdr *nlh,
+static int dccp_diag_dump_one(struct netlink_callback *cb,
const struct inet_diag_req_v2 *req)
{
- return inet_diag_dump_one_icsk(&dccp_hashinfo, in_skb, nlh, req);
+ return inet_diag_dump_one_icsk(&dccp_hashinfo, cb, req);
}
static const struct inet_diag_handler dccp_diag_handler = {
diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index f11e997e517b..d2ecff3195ba 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -157,11 +157,9 @@ int inet_diag_msg_attrs_fill(struct sock *sk, struct sk_buff *skb,
EXPORT_SYMBOL_GPL(inet_diag_msg_attrs_fill);
int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
- struct sk_buff *skb, const struct inet_diag_req_v2 *req,
- struct user_namespace *user_ns,
- u32 portid, u32 seq, u16 nlmsg_flags,
- const struct nlmsghdr *unlh,
- bool net_admin)
+ struct sk_buff *skb, struct netlink_callback *cb,
+ const struct inet_diag_req_v2 *req,
+ u16 nlmsg_flags, bool net_admin)
{
const struct tcp_congestion_ops *ca_ops;
const struct inet_diag_handler *handler;
@@ -174,8 +172,8 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
handler = inet_diag_table[req->sdiag_protocol];
BUG_ON(!handler);
- nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),
- nlmsg_flags);
+ nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
+ cb->nlh->nlmsg_type, sizeof(*r), nlmsg_flags);
if (!nlh)
return -EMSGSIZE;
@@ -187,7 +185,9 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
r->idiag_timer = 0;
r->idiag_retrans = 0;
- if (inet_diag_msg_attrs_fill(sk, skb, r, ext, user_ns, net_admin))
+ if (inet_diag_msg_attrs_fill(sk, skb, r, ext,
+ sk_user_ns(NETLINK_CB(cb->skb).sk),
+ net_admin))
goto errout;
if (ext & (1 << (INET_DIAG_MEMINFO - 1))) {
@@ -312,30 +312,19 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
}
EXPORT_SYMBOL_GPL(inet_sk_diag_fill);
-static int inet_csk_diag_fill(struct sock *sk,
- struct sk_buff *skb,
- const struct inet_diag_req_v2 *req,
- struct user_namespace *user_ns,
- u32 portid, u32 seq, u16 nlmsg_flags,
- const struct nlmsghdr *unlh,
- bool net_admin)
-{
- return inet_sk_diag_fill(sk, inet_csk(sk), skb, req, user_ns,
- portid, seq, nlmsg_flags, unlh, net_admin);
-}
-
static int inet_twsk_diag_fill(struct sock *sk,
struct sk_buff *skb,
- u32 portid, u32 seq, u16 nlmsg_flags,
- const struct nlmsghdr *unlh)
+ struct netlink_callback *cb,
+ u16 nlmsg_flags)
{
struct inet_timewait_sock *tw = inet_twsk(sk);
struct inet_diag_msg *r;
struct nlmsghdr *nlh;
long tmo;
- nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),
- nlmsg_flags);
+ nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq, cb->nlh->nlmsg_type,
+ sizeof(*r), nlmsg_flags);
if (!nlh)
return -EMSGSIZE;
@@ -359,16 +348,16 @@ static int inet_twsk_diag_fill(struct sock *sk,
}
static int inet_req_diag_fill(struct sock *sk, struct sk_buff *skb,
- u32 portid, u32 seq, u16 nlmsg_flags,
- const struct nlmsghdr *unlh, bool net_admin)
+ struct netlink_callback *cb,
+ u16 nlmsg_flags, bool net_admin)
{
struct request_sock *reqsk = inet_reqsk(sk);
struct inet_diag_msg *r;
struct nlmsghdr *nlh;
long tmo;
- nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),
- nlmsg_flags);
+ nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
+ cb->nlh->nlmsg_type, sizeof(*r), nlmsg_flags);
if (!nlh)
return -EMSGSIZE;
@@ -397,21 +386,18 @@ static int inet_req_diag_fill(struct sock *sk, struct sk_buff *skb,
}
static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
+ struct netlink_callback *cb,
const struct inet_diag_req_v2 *r,
- struct user_namespace *user_ns,
- u32 portid, u32 seq, u16 nlmsg_flags,
- const struct nlmsghdr *unlh, bool net_admin)
+ u16 nlmsg_flags, bool net_admin)
{
if (sk->sk_state == TCP_TIME_WAIT)
- return inet_twsk_diag_fill(sk, skb, portid, seq,
- nlmsg_flags, unlh);
+ return inet_twsk_diag_fill(sk, skb, cb, nlmsg_flags);
if (sk->sk_state == TCP_NEW_SYN_RECV)
- return inet_req_diag_fill(sk, skb, portid, seq,
- nlmsg_flags, unlh, net_admin);
+ return inet_req_diag_fill(sk, skb, cb, nlmsg_flags, net_admin);
- return inet_csk_diag_fill(sk, skb, r, user_ns, portid, seq,
- nlmsg_flags, unlh, net_admin);
+ return inet_sk_diag_fill(sk, inet_csk(sk), skb, cb, r, nlmsg_flags,
+ net_admin);
}
struct sock *inet_diag_find_one_icsk(struct net *net,
@@ -459,10 +445,10 @@ struct sock *inet_diag_find_one_icsk(struct net *net,
EXPORT_SYMBOL_GPL(inet_diag_find_one_icsk);
int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo,
- struct sk_buff *in_skb,
- const struct nlmsghdr *nlh,
+ struct netlink_callback *cb,
const struct inet_diag_req_v2 *req)
{
+ struct sk_buff *in_skb = cb->skb;
bool net_admin = netlink_net_capable(in_skb, CAP_NET_ADMIN);
struct net *net = sock_net(in_skb->sk);
struct sk_buff *rep;
@@ -479,10 +465,7 @@ int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo,
goto out;
}
- err = sk_diag_fill(sk, rep, req,
- sk_user_ns(NETLINK_CB(in_skb).sk),
- NETLINK_CB(in_skb).portid,
- nlh->nlmsg_seq, 0, nlh, net_admin);
+ err = sk_diag_fill(sk, rep, cb, req, 0, net_admin);
if (err < 0) {
WARN_ON(err == -EMSGSIZE);
nlmsg_free(rep);
@@ -509,14 +492,19 @@ static int inet_diag_cmd_exact(int cmd, struct sk_buff *in_skb,
int err;
handler = inet_diag_lock_handler(req->sdiag_protocol);
- if (IS_ERR(handler))
+ if (IS_ERR(handler)) {
err = PTR_ERR(handler);
- else if (cmd == SOCK_DIAG_BY_FAMILY)
- err = handler->dump_one(in_skb, nlh, req);
- else if (cmd == SOCK_DESTROY && handler->destroy)
+ } else if (cmd == SOCK_DIAG_BY_FAMILY) {
+ struct netlink_callback cb = {
+ .nlh = nlh,
+ .skb = in_skb,
+ };
+ err = handler->dump_one(&cb, req);
+ } else if (cmd == SOCK_DESTROY && handler->destroy) {
err = handler->destroy(in_skb, req);
- else
+ } else {
err = -EOPNOTSUPP;
+ }
inet_diag_unlock_handler(handler);
return err;
@@ -847,23 +835,6 @@ static int inet_diag_bc_audit(const struct nlattr *attr,
return len == 0 ? 0 : -EINVAL;
}
-static int inet_csk_diag_dump(struct sock *sk,
- struct sk_buff *skb,
- struct netlink_callback *cb,
- const struct inet_diag_req_v2 *r,
- const struct nlattr *bc,
- bool net_admin)
-{
- if (!inet_diag_bc_sk(bc, sk))
- return 0;
-
- return inet_csk_diag_fill(sk, skb, r,
- sk_user_ns(NETLINK_CB(cb->skb).sk),
- NETLINK_CB(cb->skb).portid,
- cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh,
- net_admin);
-}
-
static void twsk_build_assert(void)
{
BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_family) !=
@@ -935,8 +906,12 @@ void inet_diag_dump_icsk(struct inet_hashinfo *hashinfo, struct sk_buff *skb,
r->id.idiag_sport)
goto next_listen;
- if (inet_csk_diag_dump(sk, skb, cb, r,
- bc, net_admin) < 0) {
+ if (!inet_diag_bc_sk(bc, sk))
+ goto next_listen;
+
+ if (inet_sk_diag_fill(sk, inet_csk(sk), skb,
+ cb, r, NLM_F_MULTI,
+ net_admin) < 0) {
spin_unlock(&ilb->lock);
goto done;
}
@@ -1014,11 +989,8 @@ void inet_diag_dump_icsk(struct inet_hashinfo *hashinfo, struct sk_buff *skb,
res = 0;
for (idx = 0; idx < accum; idx++) {
if (res >= 0) {
- res = sk_diag_fill(sk_arr[idx], skb, r,
- sk_user_ns(NETLINK_CB(cb->skb).sk),
- NETLINK_CB(cb->skb).portid,
- cb->nlh->nlmsg_seq, NLM_F_MULTI,
- cb->nlh, net_admin);
+ res = sk_diag_fill(sk_arr[idx], skb, cb, r,
+ NLM_F_MULTI, net_admin);
if (res < 0)
num = num_arr[idx];
}
diff --git a/net/ipv4/raw_diag.c b/net/ipv4/raw_diag.c
index e35736b99300..a2933eeabd91 100644
--- a/net/ipv4/raw_diag.c
+++ b/net/ipv4/raw_diag.c
@@ -87,15 +87,16 @@ static struct sock *raw_sock_get(struct net *net, const struct inet_diag_req_v2
return sk ? sk : ERR_PTR(-ENOENT);
}
-static int raw_diag_dump_one(struct sk_buff *in_skb,
- const struct nlmsghdr *nlh,
+static int raw_diag_dump_one(struct netlink_callback *cb,
const struct inet_diag_req_v2 *r)
{
- struct net *net = sock_net(in_skb->sk);
+ struct sk_buff *in_skb = cb->skb;
struct sk_buff *rep;
struct sock *sk;
+ struct net *net;
int err;
+ net = sock_net(in_skb->sk);
sk = raw_sock_get(net, r);
if (IS_ERR(sk))
return PTR_ERR(sk);
@@ -108,10 +109,7 @@ static int raw_diag_dump_one(struct sk_buff *in_skb,
return -ENOMEM;
}
- err = inet_sk_diag_fill(sk, NULL, rep, r,
- sk_user_ns(NETLINK_CB(in_skb).sk),
- NETLINK_CB(in_skb).portid,
- nlh->nlmsg_seq, 0, nlh,
+ err = inet_sk_diag_fill(sk, NULL, rep, cb, r, 0,
netlink_net_capable(in_skb, CAP_NET_ADMIN));
sock_put(sk);
@@ -136,11 +134,7 @@ static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
if (!inet_diag_bc_sk(bc, sk))
return 0;
- return inet_sk_diag_fill(sk, NULL, skb, r,
- sk_user_ns(NETLINK_CB(cb->skb).sk),
- NETLINK_CB(cb->skb).portid,
- cb->nlh->nlmsg_seq, NLM_F_MULTI,
- cb->nlh, net_admin);
+ return inet_sk_diag_fill(sk, NULL, skb, cb, r, NLM_F_MULTI, net_admin);
}
static void raw_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
diff --git a/net/ipv4/tcp_diag.c b/net/ipv4/tcp_diag.c
index 0d08f9e2d8d0..bcd3a26efff1 100644
--- a/net/ipv4/tcp_diag.c
+++ b/net/ipv4/tcp_diag.c
@@ -184,10 +184,10 @@ static void tcp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
inet_diag_dump_icsk(&tcp_hashinfo, skb, cb, r, bc);
}
-static int tcp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
+static int tcp_diag_dump_one(struct netlink_callback *cb,
const struct inet_diag_req_v2 *req)
{
- return inet_diag_dump_one_icsk(&tcp_hashinfo, in_skb, nlh, req);
+ return inet_diag_dump_one_icsk(&tcp_hashinfo, cb, req);
}
#ifdef CONFIG_INET_DIAG_DESTROY
diff --git a/net/ipv4/udp_diag.c b/net/ipv4/udp_diag.c
index 910555a4d9fe..7d65a6a5cd51 100644
--- a/net/ipv4/udp_diag.c
+++ b/net/ipv4/udp_diag.c
@@ -21,16 +21,15 @@ static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
if (!inet_diag_bc_sk(bc, sk))
return 0;
- return inet_sk_diag_fill(sk, NULL, skb, req,
- sk_user_ns(NETLINK_CB(cb->skb).sk),
- NETLINK_CB(cb->skb).portid,
- cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh, net_admin);
+ return inet_sk_diag_fill(sk, NULL, skb, cb, req, NLM_F_MULTI,
+ net_admin);
}
-static int udp_dump_one(struct udp_table *tbl, struct sk_buff *in_skb,
- const struct nlmsghdr *nlh,
+static int udp_dump_one(struct udp_table *tbl,
+ struct netlink_callback *cb,
const struct inet_diag_req_v2 *req)
{
+ struct sk_buff *in_skb = cb->skb;
int err = -EINVAL;
struct sock *sk = NULL;
struct sk_buff *rep;
@@ -70,11 +69,8 @@ static int udp_dump_one(struct udp_table *tbl, struct sk_buff *in_skb,
if (!rep)
goto out;
- err = inet_sk_diag_fill(sk, NULL, rep, req,
- sk_user_ns(NETLINK_CB(in_skb).sk),
- NETLINK_CB(in_skb).portid,
- nlh->nlmsg_seq, 0, nlh,
- netlink_net_capable(in_skb, CAP_NET_ADMIN));
+ err = inet_sk_diag_fill(sk, NULL, rep, cb, req, 0,
+ netlink_net_capable(in_skb, CAP_NET_ADMIN));
if (err < 0) {
WARN_ON(err == -EMSGSIZE);
kfree_skb(rep);
@@ -151,10 +147,10 @@ static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
udp_dump(&udp_table, skb, cb, r, bc);
}
-static int udp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
+static int udp_diag_dump_one(struct netlink_callback *cb,
const struct inet_diag_req_v2 *req)
{
- return udp_dump_one(&udp_table, in_skb, nlh, req);
+ return udp_dump_one(&udp_table, cb, req);
}
static void udp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
@@ -255,10 +251,10 @@ static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
udp_dump(&udplite_table, skb, cb, r, bc);
}
-static int udplite_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
+static int udplite_diag_dump_one(struct netlink_callback *cb,
const struct inet_diag_req_v2 *req)
{
- return udp_dump_one(&udplite_table, in_skb, nlh, req);
+ return udp_dump_one(&udplite_table, cb, req);
}
static const struct inet_diag_handler udplite_diag_handler = {
diff --git a/net/sctp/diag.c b/net/sctp/diag.c
index 8a15146faaeb..bed6436cd0af 100644
--- a/net/sctp/diag.c
+++ b/net/sctp/diag.c
@@ -432,11 +432,12 @@ static void sctp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
sctp_get_sctp_info(sk, infox->asoc, infox->sctpinfo);
}
-static int sctp_diag_dump_one(struct sk_buff *in_skb,
- const struct nlmsghdr *nlh,
+static int sctp_diag_dump_one(struct netlink_callback *cb,
const struct inet_diag_req_v2 *req)
{
+ struct sk_buff *in_skb = cb->skb;
struct net *net = sock_net(in_skb->sk);
+ const struct nlmsghdr *nlh = cb->nlh;
union sctp_addr laddr, paddr;
struct sctp_comm_param commp = {
.skb = in_skb,
--
2.17.1
next prev parent reply other threads:[~2020-02-25 23:04 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-25 23:04 [PATCH bpf-next v2 0/4] Provide bpf_sk_storage data in INET_DIAG Martin KaFai Lau
2020-02-25 23:04 ` Martin KaFai Lau [this message]
2020-02-25 23:04 ` [PATCH bpf-next v2 2/4] inet_diag: Move the INET_DIAG_REQ_BYTECODE nlattr to cb->data Martin KaFai Lau
2020-02-25 23:04 ` [PATCH bpf-next v2 3/4] bpf: INET_DIAG support in bpf_sk_storage Martin KaFai Lau
2020-02-25 23:04 ` [PATCH bpf-next v2 4/4] bpf: inet_diag: Dump bpf_sk_storages in inet_diag_dump() Martin KaFai Lau
2020-02-26 17:21 ` Daniel Borkmann
2020-02-27 1:34 ` Martin KaFai Lau
2020-02-27 6:16 ` Yonghong Song
2020-02-27 23:45 ` Daniel Borkmann
2020-02-28 2:57 ` Alexei Starovoitov
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