From e9d9da91548b21e189fcd0259a0f2d26d1afc509 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 17 Mar 2023 15:55:39 +0000 Subject: tcp: preserve const qualifier in tcp_sk() We can change tcp_sk() to propagate its argument const qualifier, thanks to container_of_const(). We have two places where a const sock pointer has to be upgraded to a write one. We have been using const qualifier for lockless listeners to clearly identify points where writes could happen. Add tcp_sk_rw() helper to better document these. tcp_inbound_md5_hash(), __tcp_grow_window(), tcp_reset_check() and tcp_rack_reo_wnd() get an additional const qualififer for their @tp local variables. smc_check_reset_syn_req() also needs a similar change. Signed-off-by: Eric Dumazet Reviewed-by: Simon Horman Signed-off-by: David S. Miller --- net/ipv4/tcp_input.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/ipv4/tcp_input.c') diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 754ddbe0577f..2b75cd9e2e92 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -458,7 +458,7 @@ static void tcp_sndbuf_expand(struct sock *sk) static int __tcp_grow_window(const struct sock *sk, const struct sk_buff *skb, unsigned int skbtruesize) { - struct tcp_sock *tp = tcp_sk(sk); + const struct tcp_sock *tp = tcp_sk(sk); /* Optimize this! */ int truesize = tcp_win_from_space(sk, skbtruesize) >> 1; int window = tcp_win_from_space(sk, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[2])) >> 1; @@ -5693,7 +5693,7 @@ static void tcp_urg(struct sock *sk, struct sk_buff *skb, const struct tcphdr *t */ static bool tcp_reset_check(const struct sock *sk, const struct sk_buff *skb) { - struct tcp_sock *tp = tcp_sk(sk); + const struct tcp_sock *tp = tcp_sk(sk); return unlikely(TCP_SKB_CB(skb)->seq == (tp->rcv_nxt - 1) && (1 << sk->sk_state) & (TCPF_CLOSE_WAIT | TCPF_LAST_ACK | -- cgit v1.2.3