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-rw-r--r--net/ipv4/tcp.c105
1 files changed, 66 insertions, 39 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 54dda47a9a56..769e1f683471 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -488,9 +488,19 @@ static void tcp_tx_timestamp(struct sock *sk, u16 tsflags)
static inline bool tcp_stream_is_readable(const struct tcp_sock *tp,
int target, struct sock *sk)
{
- return (READ_ONCE(tp->rcv_nxt) - tp->copied_seq >= target) ||
- (sk->sk_prot->stream_memory_read ?
- sk->sk_prot->stream_memory_read(sk) : false);
+ int avail = READ_ONCE(tp->rcv_nxt) - READ_ONCE(tp->copied_seq);
+
+ if (avail > 0) {
+ if (avail >= target)
+ return true;
+ if (tcp_rmem_pressure(sk))
+ return true;
+ if (tcp_receive_window(tp) <= inet_csk(sk)->icsk_ack.rcv_mss)
+ return true;
+ }
+ if (sk->sk_prot->stream_memory_read)
+ return sk->sk_prot->stream_memory_read(sk);
+ return false;
}
/*
@@ -557,7 +567,7 @@ __poll_t tcp_poll(struct file *file, struct socket *sock, poll_table *wait)
(state != TCP_SYN_RECV || tp->fastopen_rsk)) {
int target = sock_rcvlowat(sk, 0, INT_MAX);
- if (tp->urg_seq == tp->copied_seq &&
+ if (tp->urg_seq == READ_ONCE(tp->copied_seq) &&
!sock_flag(sk, SOCK_URGINLINE) &&
tp->urg_data)
target++;
@@ -618,7 +628,7 @@ int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg)
unlock_sock_fast(sk, slow);
break;
case SIOCATMARK:
- answ = tp->urg_data && tp->urg_seq == tp->copied_seq;
+ answ = tp->urg_data && tp->urg_seq == READ_ONCE(tp->copied_seq);
break;
case SIOCOUTQ:
if (sk->sk_state == TCP_LISTEN)
@@ -627,7 +637,7 @@ int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg)
if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV))
answ = 0;
else
- answ = tp->write_seq - tp->snd_una;
+ answ = READ_ONCE(tp->write_seq) - tp->snd_una;
break;
case SIOCOUTQNSD:
if (sk->sk_state == TCP_LISTEN)
@@ -636,7 +646,7 @@ int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg)
if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV))
answ = 0;
else
- answ = tp->write_seq - tp->snd_nxt;
+ answ = READ_ONCE(tp->write_seq) - tp->snd_nxt;
break;
default:
return -ENOIOCTLCMD;
@@ -1027,7 +1037,7 @@ new_segment:
sk->sk_wmem_queued += copy;
sk_mem_charge(sk, copy);
skb->ip_summed = CHECKSUM_PARTIAL;
- tp->write_seq += copy;
+ WRITE_ONCE(tp->write_seq, tp->write_seq + copy);
TCP_SKB_CB(skb)->end_seq += copy;
tcp_skb_pcount_set(skb, 0);
@@ -1381,7 +1391,7 @@ new_segment:
if (!copied)
TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_PSH;
- tp->write_seq += copy;
+ WRITE_ONCE(tp->write_seq, tp->write_seq + copy);
TCP_SKB_CB(skb)->end_seq += copy;
tcp_skb_pcount_set(skb, 0);
@@ -1686,9 +1696,9 @@ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc,
sk_eat_skb(sk, skb);
if (!desc->count)
break;
- tp->copied_seq = seq;
+ WRITE_ONCE(tp->copied_seq, seq);
}
- tp->copied_seq = seq;
+ WRITE_ONCE(tp->copied_seq, seq);
tcp_rcv_space_adjust(sk);
@@ -1774,10 +1784,11 @@ static int tcp_zerocopy_receive(struct sock *sk,
down_read(&current->mm->mmap_sem);
- ret = -EINVAL;
vma = find_vma(current->mm, address);
- if (!vma || vma->vm_start > address || vma->vm_ops != &tcp_vm_ops)
- goto out;
+ if (!vma || vma->vm_start > address || vma->vm_ops != &tcp_vm_ops) {
+ up_read(&current->mm->mmap_sem);
+ return -EINVAL;
+ }
zc->length = min_t(unsigned long, zc->length, vma->vm_end - address);
tp = tcp_sk(sk);
@@ -1824,7 +1835,7 @@ static int tcp_zerocopy_receive(struct sock *sk,
out:
up_read(&current->mm->mmap_sem);
if (length) {
- tp->copied_seq = seq;
+ WRITE_ONCE(tp->copied_seq, seq);
tcp_rcv_space_adjust(sk);
/* Clean up data we have read: This will do ACK frames. */
@@ -2029,7 +2040,7 @@ int tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock,
/* Well, if we have backlog, try to process it now yet. */
- if (copied >= target && !sk->sk_backlog.tail)
+ if (copied >= target && !READ_ONCE(sk->sk_backlog.tail))
break;
if (copied) {
@@ -2101,7 +2112,7 @@ int tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock,
if (urg_offset < used) {
if (!urg_offset) {
if (!sock_flag(sk, SOCK_URGINLINE)) {
- ++*seq;
+ WRITE_ONCE(*seq, *seq + 1);
urg_hole++;
offset++;
used--;
@@ -2123,7 +2134,7 @@ int tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock,
}
}
- *seq += used;
+ WRITE_ONCE(*seq, *seq + used);
copied += used;
len -= used;
@@ -2134,14 +2145,16 @@ skip_copy:
tp->urg_data = 0;
tcp_fast_path_check(sk);
}
- if (used + offset < skb->len)
- continue;
if (TCP_SKB_CB(skb)->has_rxtstamp) {
tcp_update_recv_tstamps(skb, &tss);
has_tss = true;
has_cmsg = true;
}
+
+ if (used + offset < skb->len)
+ continue;
+
if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)
goto found_fin_ok;
if (!(flags & MSG_PEEK))
@@ -2150,7 +2163,7 @@ skip_copy:
found_fin_ok:
/* Process the FIN. */
- ++*seq;
+ WRITE_ONCE(*seq, *seq + 1);
if (!(flags & MSG_PEEK))
sk_eat_skb(sk, skb);
break;
@@ -2543,6 +2556,7 @@ int tcp_disconnect(struct sock *sk, int flags)
struct inet_connection_sock *icsk = inet_csk(sk);
struct tcp_sock *tp = tcp_sk(sk);
int old_state = sk->sk_state;
+ u32 seq;
if (old_state != TCP_CLOSE)
tcp_set_state(sk, TCP_CLOSE);
@@ -2565,7 +2579,7 @@ int tcp_disconnect(struct sock *sk, int flags)
tcp_clear_xmit_timers(sk);
__skb_queue_purge(&sk->sk_receive_queue);
- tp->copied_seq = tp->rcv_nxt;
+ WRITE_ONCE(tp->copied_seq, tp->rcv_nxt);
tp->urg_data = 0;
tcp_write_queue_purge(sk);
tcp_fastopen_active_disable_ofo_check(sk);
@@ -2580,9 +2594,12 @@ int tcp_disconnect(struct sock *sk, int flags)
sock_reset_flag(sk, SOCK_DONE);
tp->srtt_us = 0;
tp->rcv_rtt_last_tsecr = 0;
- tp->write_seq += tp->max_window + 2;
- if (tp->write_seq == 0)
- tp->write_seq = 1;
+
+ seq = tp->write_seq + tp->max_window + 2;
+ if (!seq)
+ seq = 1;
+ WRITE_ONCE(tp->write_seq, seq);
+
tp->snd_cwnd = 2;
icsk->icsk_probes_out = 0;
tp->snd_ssthresh = TCP_INFINITE_SSTHRESH;
@@ -2590,6 +2607,9 @@ int tcp_disconnect(struct sock *sk, int flags)
tp->window_clamp = 0;
tp->delivered = 0;
tp->delivered_ce = 0;
+ if (icsk->icsk_ca_ops->release)
+ icsk->icsk_ca_ops->release(sk);
+ memset(icsk->icsk_ca_priv, 0, sizeof(icsk->icsk_ca_priv));
tcp_set_ca_state(sk, TCP_CA_Open);
tp->is_sack_reneg = 0;
tcp_clear_retrans(tp);
@@ -2866,16 +2886,23 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
break;
case TCP_QUEUE_SEQ:
- if (sk->sk_state != TCP_CLOSE)
+ if (sk->sk_state != TCP_CLOSE) {
err = -EPERM;
- else if (tp->repair_queue == TCP_SEND_QUEUE)
- tp->write_seq = val;
- else if (tp->repair_queue == TCP_RECV_QUEUE) {
- WRITE_ONCE(tp->rcv_nxt, val);
- WRITE_ONCE(tp->copied_seq, val);
- }
- else
+ } else if (tp->repair_queue == TCP_SEND_QUEUE) {
+ if (!tcp_rtx_queue_empty(sk))
+ err = -EPERM;
+ else
+ WRITE_ONCE(tp->write_seq, val);
+ } else if (tp->repair_queue == TCP_RECV_QUEUE) {
+ if (tp->rcv_nxt != tp->copied_seq) {
+ err = -EPERM;
+ } else {
+ WRITE_ONCE(tp->rcv_nxt, val);
+ WRITE_ONCE(tp->copied_seq, val);
+ }
+ } else {
err = -EINVAL;
+ }
break;
case TCP_REPAIR_OPTIONS:
@@ -3001,10 +3028,7 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
#ifdef CONFIG_TCP_MD5SIG
case TCP_MD5SIG:
case TCP_MD5SIG_EXT:
- if ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))
- err = tp->af_specific->md5_parse(sk, optname, optval, optlen);
- else
- err = -EINVAL;
+ err = tp->af_specific->md5_parse(sk, optname, optval, optlen);
break;
#endif
case TCP_USER_TIMEOUT:
@@ -3742,10 +3766,13 @@ EXPORT_SYMBOL(tcp_md5_hash_skb_data);
int tcp_md5_hash_key(struct tcp_md5sig_pool *hp, const struct tcp_md5sig_key *key)
{
+ u8 keylen = READ_ONCE(key->keylen); /* paired with WRITE_ONCE() in tcp_md5_do_add */
struct scatterlist sg;
- sg_init_one(&sg, key->key, key->keylen);
- ahash_request_set_crypt(hp->md5_req, &sg, NULL, key->keylen);
+ sg_init_one(&sg, key->key, keylen);
+ ahash_request_set_crypt(hp->md5_req, &sg, NULL, keylen);
+
+ /* tcp_md5_do_add() might change key->key under us */
return crypto_ahash_update(hp->md5_req);
}
EXPORT_SYMBOL(tcp_md5_hash_key);