1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2020 Facebook */
3 #include "bpf_iter.h"
4 #include "bpf_tracing_net.h"
5 #include <bpf/bpf_helpers.h>
6
7 char _license[] SEC("license") = "GPL";
8
SOCK_INODE(struct socket * socket)9 static __attribute__((noinline)) struct inode *SOCK_INODE(struct socket *socket)
10 {
11 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
12 }
13
14 SEC("iter/netlink")
dump_netlink(struct bpf_iter__netlink * ctx)15 int dump_netlink(struct bpf_iter__netlink *ctx)
16 {
17 struct seq_file *seq = ctx->meta->seq;
18 struct netlink_sock *nlk = ctx->sk;
19 unsigned long group, ino;
20 struct inode *inode;
21 struct socket *sk;
22 struct sock *s;
23
24 if (nlk == (void *)0)
25 return 0;
26
27 if (ctx->meta->seq_num == 0)
28 BPF_SEQ_PRINTF(seq, "sk Eth Pid Groups "
29 "Rmem Wmem Dump Locks Drops "
30 "Inode\n");
31
32 s = &nlk->sk;
33 BPF_SEQ_PRINTF(seq, "%pK %-3d ", s, s->sk_protocol);
34
35 if (!nlk->groups) {
36 group = 0;
37 } else {
38 /* FIXME: temporary use bpf_probe_read_kernel here, needs
39 * verifier support to do direct access.
40 */
41 bpf_probe_read_kernel(&group, sizeof(group), &nlk->groups[0]);
42 }
43 BPF_SEQ_PRINTF(seq, "%-10u %08x %-8d %-8d %-5d %-8d ",
44 nlk->portid, (u32)group,
45 s->sk_rmem_alloc.counter,
46 s->sk_wmem_alloc.refs.counter - 1,
47 nlk->cb_running, s->sk_refcnt.refs.counter);
48
49 sk = s->sk_socket;
50 if (!sk) {
51 ino = 0;
52 } else {
53 /* FIXME: container_of inside SOCK_INODE has a forced
54 * type conversion, and direct access cannot be used
55 * with current verifier.
56 */
57 inode = SOCK_INODE(sk);
58 bpf_probe_read_kernel(&ino, sizeof(ino), &inode->i_ino);
59 }
60 BPF_SEQ_PRINTF(seq, "%-8u %-8lu\n", s->sk_drops.counter, ino);
61
62 return 0;
63 }
64