From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELtrYJgdqhKTlw7WM/MiYzj3/akeab9DU7Z9+6aVOGG9Gf+3gi7R5xtwAydh16Hdx+cY6s2W ARC-Seal: i=1; a=rsa-sha256; t=1520641336; cv=none; d=google.com; s=arc-20160816; b=XEv/7Cq7SrPSMwa3TCKwNyCRf5ikXemkEPpk6FitktuFPO3Gg/Ljg9CLQ+rjVbp+KD cGB6WjZNQjQ9ssXPOQgPOkfZwyHFM3xYtvkKSg1OSVUjk0hXzc/7tX+m/zfXFkA/IAe+ kjieD8XiijshKNmb/fNmXKS7Npuj5ZPIfzNp/ftWHQ88IXipxGSe0Q16J8/C0NekVNTq RcFJ0fC/nSByRtI3zWaQJr3surSfM0rWUTO70GrLISbMlwxMgkc+oGc79fdDtKXEOGNX febC2c8wha8rFPozUdT7sH6EL5bcAPxImsgdUptnLFUvCAqudxhedtv1wK5D+/IlFL6b CkGg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=k0ggsUCzlruSUc+IMO7CIIPVO74LG231s8RrMnw51LA=; b=WV45kl6qjCF1Ln6RCSxTlvlWtsJUu2zoZlZ7sNEpnGIeaf/cpT1jtJoVzuwGqSN7RD 99URNIG1/FXrdePrE08jajVy0rlooK9iuQCHWjRA8nNmPTexWXaFmcY3IYXVYAK20ckw PPfbK5IYXaYJBoTzwRkiPFkurOGuGFuMvSexGa8XqE+4Rwz6XfNNCOKB31fjlWdQRwO1 JTu/V3GgJIl3Y4WXaDZ4oWsycZ2Dcpb1xYbzLbMorjeXYnLNsvDEZabysmlR6BTK6ilf +o9vt2b2nJA01pD1DHrNxRfCuL4DRWCUT9wAL3Hi03LrPyAzQps9S0etSWwYDqBVDx6l zQ9Q== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 185.236.200.248 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org Authentication-Results: mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 185.236.200.248 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ilya Lesokhin , "David S. Miller" Subject: [PATCH 4.9 45/65] tcp: Honor the eor bit in tcp_mtu_probe Date: Fri, 9 Mar 2018 16:18:45 -0800 Message-Id: <20180310001828.552511501@linuxfoundation.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180310001824.927996722@linuxfoundation.org> References: <20180310001824.927996722@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1594508010277988788?= X-GMAIL-MSGID: =?utf-8?q?1594508010277988788?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ilya Lesokhin [ Upstream commit 808cf9e38cd7923036a99f459ccc8cf2955e47af ] Avoid SKB coalescing if eor bit is set in one of the relevant SKBs. Fixes: c134ecb87817 ("tcp: Make use of MSG_EOR in tcp_sendmsg") Signed-off-by: Ilya Lesokhin Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/tcp_output.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -1907,6 +1907,24 @@ static inline void tcp_mtu_check_reprobe } } +static bool tcp_can_coalesce_send_queue_head(struct sock *sk, int len) +{ + struct sk_buff *skb, *next; + + skb = tcp_send_head(sk); + tcp_for_write_queue_from_safe(skb, next, sk) { + if (len <= skb->len) + break; + + if (unlikely(TCP_SKB_CB(skb)->eor)) + return false; + + len -= skb->len; + } + + return true; +} + /* Create a new MTU probe if we are ready. * MTU probe is regularly attempting to increase the path MTU by * deliberately sending larger packets. This discovers routing @@ -1979,6 +1997,9 @@ static int tcp_mtu_probe(struct sock *sk return 0; } + if (!tcp_can_coalesce_send_queue_head(sk, probe_size)) + return -1; + /* We're allowed to probe. Build it now. */ nskb = sk_stream_alloc_skb(sk, probe_size, GFP_ATOMIC, false); if (!nskb) @@ -2014,6 +2035,10 @@ static int tcp_mtu_probe(struct sock *sk /* We've eaten all the data from this skb. * Throw it away. */ TCP_SKB_CB(nskb)->tcp_flags |= TCP_SKB_CB(skb)->tcp_flags; + /* If this is the last SKB we copy and eor is set + * we need to propagate it to the new skb. + */ + TCP_SKB_CB(nskb)->eor = TCP_SKB_CB(skb)->eor; tcp_unlink_write_queue(skb, sk); sk_wmem_free_skb(sk, skb); } else {