From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AC27DC10F0B for ; Sat, 23 Feb 2019 19:07:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 79E2C206A3 for ; Sat, 23 Feb 2019 19:07:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="vGNaPzli" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726899AbfBWTHO (ORCPT ); Sat, 23 Feb 2019 14:07:14 -0500 Received: from mail-pf1-f202.google.com ([209.85.210.202]:50103 "EHLO mail-pf1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726217AbfBWTHN (ORCPT ); Sat, 23 Feb 2019 14:07:13 -0500 Received: by mail-pf1-f202.google.com with SMTP id y66so4443786pfg.16 for ; Sat, 23 Feb 2019 11:07:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=tpMoXfEShFjaioesuDxP+LD9xmvC7EP/PPC2O+OQ6uU=; b=vGNaPzliswA0k73HPkX1cv/19ZanDe61CNkMIHKYnuleDcw7sNzaEiUCgdghL1WWD0 UKJIlAHcufbHCMs9EvxVimpEPkZWRRAs5Iy3M0Q4Th3h7BSftNlUx5etXrqwVRAxrY43 OU9hzbRaeIw1LW+w7nJz2GEehXwJ9X6h2J5Pgyv84+l/tz4pD9fQzMkBP5mU2CnqcK8r Q6EksRY9zpEj6No9zAVfOLsPLscQVYPHR353dPlejeOvKwD8Ki9CVc4fIxbZRDQ7Qh+Z dn5+i7znzePxMKiepJzgQ3/LixoPxF6I8ZiCj94Fiiy1LsD2CJAGsKzdfGUYmjYpyZfA kmOA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=tpMoXfEShFjaioesuDxP+LD9xmvC7EP/PPC2O+OQ6uU=; b=UUOJEyEv0p1KsQBR2+8huff9v7IVR0IgPiCKmPR+yM+55ULvdudWN3JYRKJTEgz0yR gqMxfUuxUQRmxmYMI0tXPQaZFahi/VjGa2zJaGSZCtuI3aV/KAxJhJl45aIdxA1KPwRM qmoACJSSskiRZQ+DnZP7QCV8+8l005akLg8rCap9lv7aYS/Tki2a4x6WBw3UIkKAY9dY tRL6mISM2ExDJqZusptI9Up+1tnolr0QnkEZEpg9Lzwp4KoYKhlvG3yB1zp/NFYzeJcq yrMseK4RTM5ZpByv08j+X488e1YXZxseFfpr0Oed9kaoSUevWzTdp2fMh46RdpGxx4iV x/lA== X-Gm-Message-State: AHQUAub1gEbs2YVDkBaX8Nu6goryak6cUfT7pjJdZbkOnJ12FyEQcB/n mkX1LAeVyze8XUvmUSgMkRYpy2x+m28CIQ== X-Google-Smtp-Source: AHgI3IYby9VJraSFO60SGeXqy0rvzUy06jiPMhJBx2x38S15WV1OvYskPiCz3waeUlFnsArnqGVJXE0t75/wDg== X-Received: by 2002:a62:1f12:: with SMTP id f18mr3849735pff.49.1550948833005; Sat, 23 Feb 2019 11:07:13 -0800 (PST) Date: Sat, 23 Feb 2019 11:07:09 -0800 Message-Id: <20190223190709.61558-1-edumazet@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.21.0.rc0.258.g878e2cd30e-goog Subject: [PATCH bpf] bpf: properly check TCP_CONGESTION optlen From: Eric Dumazet To: Alexei Starovoitov Cc: Daniel Borkmann , netdev , Eric Dumazet , Eric Dumazet , Martin KaFai Lau , Song Liu , Yonghong Song , bpf , Lawrence Brakmo Content-Type: text/plain; charset="UTF-8" Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org If caller of bpf_setsockopt() is silly passing a negative optlen bad things happen. Fixes: 91b5b21c7c16 ("bpf: Add support for changing congestion control") Signed-off-by: Eric Dumazet Cc: Lawrence Brakmo --- net/core/filter.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/net/core/filter.c b/net/core/filter.c index f7d0004fc16096eb42ece3a6acf645540ee2326b..6a5d89464168f2f35f43986c1dbc0446c9390a3c 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -4194,8 +4194,9 @@ BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock, char name[TCP_CA_NAME_MAX]; bool reinit = bpf_sock->op > BPF_SOCK_OPS_NEEDS_ECN; - strncpy(name, optval, min_t(long, optlen, - TCP_CA_NAME_MAX-1)); + if (optlen < 0) + return -EINVAL; + strncpy(name, optval, min(optlen, TCP_CA_NAME_MAX - 1)); name[TCP_CA_NAME_MAX-1] = 0; ret = tcp_set_congestion_control(sk, name, false, reinit); -- 2.21.0.rc0.258.g878e2cd30e-goog