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| author | Eric Dumazet <edumazet@google.com> | 2026-04-16 20:03:14 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-04-18 11:10:13 -0700 |
| commit | a984705ca88b976bf1087978fd98b7f3993da88c (patch) | |
| tree | 2987024d765c98a008c6747ca81bd74d9412453c /net/ipv4 | |
| parent | 5efc7b9f7cbd43401f1af81d3d7f2be00f93390d (diff) | |
| download | lwn-a984705ca88b976bf1087978fd98b7f3993da88c.tar.gz lwn-a984705ca88b976bf1087978fd98b7f3993da88c.zip | |
tcp: annotate data-races around tp->dsack_dups
tcp_get_timestamping_opt_stats() intentionally runs lockless, we must
add READ_ONCE() and WRITE_ONCE() annotations to keep KCSAN happy.
Fixes: 7e10b6554ff2 ("tcp: add dsack blocks received stats")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260416200319.3608680-10-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/tcp.c | 2 | ||||
| -rw-r--r-- | net/ipv4/tcp_input.c | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 8c84639dc54b..57c4dcc8bfe9 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4465,7 +4465,7 @@ struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk, TCP_NLA_PAD); nla_put_u64_64bit(stats, TCP_NLA_BYTES_RETRANS, READ_ONCE(tp->bytes_retrans), TCP_NLA_PAD); - nla_put_u32(stats, TCP_NLA_DSACK_DUPS, tp->dsack_dups); + nla_put_u32(stats, TCP_NLA_DSACK_DUPS, READ_ONCE(tp->dsack_dups)); nla_put_u32(stats, TCP_NLA_REORD_SEEN, tp->reord_seen); nla_put_u32(stats, TCP_NLA_SRTT, tp->srtt_us >> 3); nla_put_u16(stats, TCP_NLA_TIMEOUT_REHASH, tp->timeout_rehash); diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index edb5013873e0..65b3ecc6be4b 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1246,7 +1246,7 @@ static u32 tcp_dsack_seen(struct tcp_sock *tp, u32 start_seq, else if (tp->tlp_high_seq && tp->tlp_high_seq == end_seq) state->flag |= FLAG_DSACK_TLP; - tp->dsack_dups += dup_segs; + WRITE_ONCE(tp->dsack_dups, tp->dsack_dups + dup_segs); /* Skip the DSACK if dup segs weren't retransmitted by sender */ if (tp->dsack_dups > tp->total_retrans) return 0; |