From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f72.google.com (mail-pj1-f72.google.com [209.85.216.72]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E862F3C0613 for ; Mon, 10 Aug 2026 18:09:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.72 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786385400; cv=none; b=h1OBUNlUQrgDs6FvOLCsIN8orAwXB1e7RgEP7/42qkOctzkWZtC9rvcze1CbCZeiX2JawuICIPdTaWVYbDQqYc1S/zrHtv5w9YcBQqd4X2mAECVFHPTqMzXUG8n3HCkwai42BLw1rRV8X4HS01DkTX3yyqFf4mk+Y7W4jZn+2kQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786385400; c=relaxed/simple; bh=Tng8g144ubL7cdWL7PLGD3awMbDgm0zKMUbyJxPrw44=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=WL9C6nojOM8yjuk17dTMGag1sogdz+txlx4pmn0XHFX4slXK9xPQ7b+EXAGEeA8eshN1b+GRkenihexwd/HSdXd0QUdJFF2QdmKdVteJ9WaH1T+ELtZYzXh2ilTY3QsPk+IYxp8SB7vVZoEaNXFfUHEfeHhQgWjVZ7hSypc9Q0w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=P6IOQknI; arc=none smtp.client-ip=209.85.216.72 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="P6IOQknI" Received: by mail-pj1-f72.google.com with SMTP id 98e67ed59e1d1-38e22137fb3so3367663a91.0 for ; Mon, 10 Aug 2026 11:09:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1786385398; x=1786990198; darn=vger.kernel.org; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:from:to:cc:subject:date:message-id:reply-to :content-type; bh=SvfrgljYlAUv+7lnNBQs3scDd9aa1SmFKhsRXetGHN4=; b=P6IOQknI0Bk+Af5kPIcsRUPTch8YK+XIr9VBVxQk26mPtt3/2RctvUlVKwpw4xaMXt pPuKmsk8O0sRPWOiWHPy/mGvXU2kH/bjStzn++ZvuBkyhnPITgOwxgEF9VWhzzjPfwZh QBUpS1VXXfks4p3xD1HwzU/d4zgTOG3fKDOI6ik17C98BXFCvawtudzPQ4gt/vS6ZVc8 30UuoOnuNvKcZVBfJWvoDhjoEmGHm88TT8PuG9V/nSBNMCGU3LdWaD7oM0prZNS7bN6d VekmkFK74WmGxyQ/t9uVLjsaERYpJYzHAomX4ElwgEUwxIe4ZcixsmigbDjlTujAVXIG 21+g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1786385398; x=1786990198; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=SvfrgljYlAUv+7lnNBQs3scDd9aa1SmFKhsRXetGHN4=; b=GthoCvCuNwsQv+z9BNey/crSk6CVAcgd1nhIPNf7l1xastpAAzkgRal0Nm8HN2hcSk rRiIbBz31rknV563E35cj3qknAg8iIWD/F7DTlYLETVJkXKfxZ0ke5LvPhHBFcpXzqyv xfkeSVz2mGNT6PmZe/IRzoXWOT0/hYUFfeXVkDTcwtu4j7BqTJvzQ/O5F2Bi5bOQ7k8o kCXXHBrcUh0qQgdeCYI1b2lcyphq1yMu7R18pyfagtVGaS3P95BV3LVZjc/pmJxJ5SCd 5hSfBgYrM+C/BC9iClmMLqCkHYL2iVuJjhexrmtpwT5yTornkUObvvohjgKiD+KEdU1H EvXQ== X-Gm-Message-State: AOJu0Yx7PaMwRX8kdR1DJ45r7rUMAP/sPZDytGCo+rPzzKyEfmwUT2xt RMnURInnVvgUucZ9O7GzIuEM+uF21qEzxyqQDxFKbHTvYnG1gc51DwioDElyqwBNUFmDeYSN9ko aQulDDP4IQaZVzf6Pgzq/wxQV9AP4SQ0CYcoR5PkvvjzdtcvOqaux5QGiu+bMtpVYkig9eZWlHr wSc8xCLIPmYWkpNVJBqVfVCHX8J8oN2Lb2AkalZgrp+TLs0sJBpjn0Izz6T/oOxS4= X-Received: from dyka37.prod.google.com ([2002:a05:7300:83a5:b0:314:fa60:e9ff]) (user=almasrymina job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:3a4f:b0:38e:57a3:f218 with SMTP id 98e67ed59e1d1-392cca5bb14mr3886435a91.13.1786385398088; Mon, 10 Aug 2026 11:09:58 -0700 (PDT) Date: Mon, 10 Aug 2026 18:09:44 +0000 In-Reply-To: <20260810180956.2348280-1-almasrymina@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260810180956.2348280-1-almasrymina@google.com> X-Mailer: git-send-email 2.55.0.679.g6767b8d81c-goog Message-ID: <20260810180956.2348280-2-almasrymina@google.com> Subject: [PATCH net v2 2/2] net: tcp: block standard payload injection into devmem skbs From: Mina Almasry To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, dev@openvswitch.org Cc: Mina Almasry , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Neal Cardwell , Kuniyuki Iwashima , Aaron Conole , Eelco Chaudron , Ilya Maximets , Jason Xing , Pavel Begunkov , Stanislav Fomichev , Bobby Eshleman , Florian Westphal Content-Type: text/plain; charset="UTF-8" Protect tcp_sendmsg_locked() from mistakenly appending non-zerocopy page fragments to unreadable devmem skbs. Create a new segment instead. Fixes: bd61848900bff ("net: devmem: Implement TX path") Cc: Pavel Begunkov Cc: Stanislav Fomichev Cc: Bobby Eshleman Signed-off-by: Mina Almasry Reviewed-by: Pavel Begunkov --- v2: No changes. v1: https://lore.kernel.org/r/20260801125308.1342897-3-almasrymina@google.com --- net/ipv4/tcp.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 455441f1b6949..186a36c698798 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1278,6 +1278,11 @@ int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size) if (copy > msg_data_left(msg)) copy = msg_data_left(msg); + if (zc != MSG_ZEROCOPY && unlikely(!skb_frags_readable(skb))) { + tcp_mark_push(tp, skb); + goto new_segment; + } + if (zc == 0) { bool merge = true; int i = skb_shinfo(skb)->nr_frags; -- 2.55.0.679.g6767b8d81c-goog