diff options
| author | Eric Dumazet <edumazet@google.com> | 2014-02-20 10:09:18 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-02-22 00:05:21 -0500 |
| commit | f5ddcbbb40aa0ba7fbfe22355d287603dbeeaaac (patch) | |
| tree | 891b56a6481cf19747018c832be557613e5b5a02 /net/ipv4/tcp_output.c | |
| parent | 68ad785c007246490b220ae958b544671339059b (diff) | |
| download | lwn-f5ddcbbb40aa0ba7fbfe22355d287603dbeeaaac.tar.gz lwn-f5ddcbbb40aa0ba7fbfe22355d287603dbeeaaac.zip | |
net-tcp: fastopen: fix high order allocations
This patch fixes two bugs in fastopen :
1) The tcp_sendmsg(..., @size) argument was ignored.
Code was relying on user not fooling the kernel with iovec mismatches
2) When MTU is about 64KB, tcp_send_syn_data() attempts order-5
allocations, which are likely to fail when memory gets fragmented.
Fixes: 783237e8daf13 ("net-tcp: Fast Open client - sending SYN-data")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Tested-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp_output.c')
| -rw-r--r-- | net/ipv4/tcp_output.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 3be16727f058..09805817627b 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -2908,7 +2908,12 @@ static int tcp_send_syn_data(struct sock *sk, struct sk_buff *syn) space = __tcp_mtu_to_mss(sk, inet_csk(sk)->icsk_pmtu_cookie) - MAX_TCP_OPTION_SPACE; - syn_data = skb_copy_expand(syn, skb_headroom(syn), space, + space = min_t(size_t, space, fo->size); + + /* limit to order-0 allocations */ + space = min_t(size_t, space, SKB_MAX_HEAD(MAX_TCP_HEADER)); + + syn_data = skb_copy_expand(syn, MAX_TCP_HEADER, space, sk->sk_allocation); if (syn_data == NULL) goto fallback; |