1 files changed, 15 insertions, 4 deletions

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 5baa8e754e41..c5429a636f1a 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1690,6 +1690,8 @@ static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i)
         const struct tcp_sock *tp = tcp_sk(sp);
         const struct inet_connection_sock *icsk = inet_csk(sp);
         const struct fastopen_queue *fastopenq = &icsk->icsk_accept_queue.fastopenq;
+        int rx_queue;
+        int state;
 
         dest  = &sp->sk_v6_daddr;
         src   = &sp->sk_v6_rcv_saddr;
@@ -1710,6 +1712,15 @@ static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i)
                 timer_expires = jiffies;
         }
 
+        state = sk_state_load(sp);
+        if (state == TCP_LISTEN)
+                rx_queue = sp->sk_ack_backlog;
+        else
+                /* Because we don't lock the socket,
+                 * we might find a transient negative value.
+                 */
+                rx_queue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0);
+
         seq_printf(seq,
                    "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
                    "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %lu %lu %u %u %d\n",
@@ -1718,9 +1729,9 @@ static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i)
                    src->s6_addr32[2], src->s6_addr32[3], srcp,
                    dest->s6_addr32[0], dest->s6_addr32[1],
                    dest->s6_addr32[2], dest->s6_addr32[3], destp,
-                   sp->sk_state,
-                   tp->write_seq-tp->snd_una,
-                   (sp->sk_state == TCP_LISTEN) ? sp->sk_ack_backlog : (tp->rcv_nxt - tp->copied_seq),
+                   state,
+                   tp->write_seq - tp->snd_una,
+                   rx_queue,
                    timer_active,
                    jiffies_delta_to_clock_t(timer_expires - jiffies),
                    icsk->icsk_retransmits,
@@ -1732,7 +1743,7 @@ static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i)
                    jiffies_to_clock_t(icsk->icsk_ack.ato),
                    (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong,
                    tp->snd_cwnd,
-                   sp->sk_state == TCP_LISTEN ?
+                   state == TCP_LISTEN ?
                         fastopenq->max_qlen :
                         (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh)
                    );