forked from luck/tmp_suning_uos_patched
3b5b0afd8d
[ Upstream commit 54ea2f49fd9400dd698c25450be3352b5613b3b4 ]
The proc socket stats use sk_prot->inuse_idx value to record inuse sock
stats. We currently do not set this correctly from sockmap side. The
result is reading sock stats '/proc/net/sockstat' gives incorrect values.
The socket counter is incremented correctly, but because we don't set the
counter correctly when we replace sk_prot we may omit the decrement.
To get the correct inuse_idx value move the core_initcall that initializes
the UDP proto handlers to late_initcall. This way it is initialized after
UDP has the chance to assign the inuse_idx value from the register protocol
handler.
Fixes: edc6741cc6 ("bpf: Add sockmap hooks for UDP sockets")
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Cong Wang <cong.wang@bytedance.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210714154750.528206-1-jakub@cloudflare.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
53 lines
1.3 KiB
C
53 lines
1.3 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/* Copyright (c) 2020 Cloudflare Ltd https://cloudflare.com */
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#include <linux/skmsg.h>
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#include <net/sock.h>
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#include <net/udp.h>
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enum {
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UDP_BPF_IPV4,
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UDP_BPF_IPV6,
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UDP_BPF_NUM_PROTS,
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};
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static struct proto *udpv6_prot_saved __read_mostly;
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static DEFINE_SPINLOCK(udpv6_prot_lock);
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static struct proto udp_bpf_prots[UDP_BPF_NUM_PROTS];
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static void udp_bpf_rebuild_protos(struct proto *prot, const struct proto *base)
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{
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*prot = *base;
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prot->unhash = sock_map_unhash;
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prot->close = sock_map_close;
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}
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static void udp_bpf_check_v6_needs_rebuild(struct proto *ops)
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{
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if (unlikely(ops != smp_load_acquire(&udpv6_prot_saved))) {
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spin_lock_bh(&udpv6_prot_lock);
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if (likely(ops != udpv6_prot_saved)) {
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udp_bpf_rebuild_protos(&udp_bpf_prots[UDP_BPF_IPV6], ops);
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smp_store_release(&udpv6_prot_saved, ops);
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}
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spin_unlock_bh(&udpv6_prot_lock);
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}
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}
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static int __init udp_bpf_v4_build_proto(void)
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{
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udp_bpf_rebuild_protos(&udp_bpf_prots[UDP_BPF_IPV4], &udp_prot);
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return 0;
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}
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late_initcall(udp_bpf_v4_build_proto);
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struct proto *udp_bpf_get_proto(struct sock *sk, struct sk_psock *psock)
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{
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int family = sk->sk_family == AF_INET ? UDP_BPF_IPV4 : UDP_BPF_IPV6;
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if (sk->sk_family == AF_INET6)
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udp_bpf_check_v6_needs_rebuild(psock->sk_proto);
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return &udp_bpf_prots[family];
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}
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