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=-6.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham 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 93FB5C2D0C3 for ; Sat, 21 Dec 2019 22:05:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 64164206B7 for ; Sat, 21 Dec 2019 22:05:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="LmAT2mjr" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726186AbfLUWFF (ORCPT ); Sat, 21 Dec 2019 17:05:05 -0500 Received: from mail-ed1-f66.google.com ([209.85.208.66]:37902 "EHLO mail-ed1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726066AbfLUWFF (ORCPT ); Sat, 21 Dec 2019 17:05:05 -0500 Received: by mail-ed1-f66.google.com with SMTP id i16so12015619edr.5 for ; Sat, 21 Dec 2019 14:05:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=message-id:in-reply-to:references:from:date:subject:fcc :content-transfer-encoding:mime-version:to:cc; bh=qrft+PiEo7aTblQ7Sc/9tnxL90PAiDzn81zSQ6uRI0U=; b=LmAT2mjrM3vt4Wl1DosGvyVjQgkWToper36VoynPXVYy0niCgQJCd2SlS41Ke9uftO VL0q6ntwzK4jX8rwq4JVI3KMwEqAI5btKSaQlGWi4A2NWOBTfw576LpX9YFwCDygXS8p sAaVCGmRbaot1iVaXY+T0YBaL6ruYMaHBfCnLh64l6LzPlx/bUQAHndnaeDLBcxG7i3M An6hJ8UdiwavvdtqimpkozLghAVwIUf9W1txsqa9O68mNCAjFC9k+nxdJB9gbZHOGYDa WnvaK7D+Gp3KdzQonOUI1pPNfUcwDonB0L7Np3kK3Ju9UoTwBK8muk7V3NlOx/9K85B0 JmRg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:in-reply-to:references:from:date :subject:fcc:content-transfer-encoding:mime-version:to:cc; bh=qrft+PiEo7aTblQ7Sc/9tnxL90PAiDzn81zSQ6uRI0U=; b=Y6zQsO18TFV+aZTyIa8XDzjKQENcEI1KpdOF6fn7tOV0Sv6pedyfNRCQcrtc2oIubb 7/3XjUDNDe4nwkrUJvVYi6QY6N8GfiOvyjdUDhghLLvK7/guZiQ/C/RsN7FL2GuyG9p3 Zc1G94iTbNRseolnX06Q5UBDq1Uxgp6dnonHoA5+U4Uix5ikMAefSGCMAnS8OqbFfqjz V3mjxaf7uHcVPwSejUvnDa8ep4yJq4fKbJUlaTjYo9ViaBbhRuyVSA/RRLUXar7o8gro QGha2iilmfthnP45vayTXh+K3rIes/+O17qSxgwDKbOWFi3TmlYQ8oefYspUInl9lL7r uMzw== X-Gm-Message-State: APjAAAWvZwL8Ug9Vqh4rgqpHWxj5VWeUC6rGASw3uuGa9/SuCwWOYF3t 0AoVpvglI6859PERK97xh79xgWW4 X-Google-Smtp-Source: APXvYqyaFZAs8giA4MpUZmGW84+kXG6VqICpPXUR0yhQ9tWc7XfQ9XwkwNmt8LEkIVPSKvI9iDPMnA== X-Received: by 2002:a05:6402:2036:: with SMTP id ay22mr24392938edb.303.1576965902959; Sat, 21 Dec 2019 14:05:02 -0800 (PST) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id t25sm1541479edt.60.2019.12.21.14.05.02 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 21 Dec 2019 14:05:02 -0800 (PST) Message-Id: In-Reply-To: References: From: "Johannes Schindelin via GitGitGadget" Date: Sat, 21 Dec 2019 22:05:00 +0000 Subject: [PATCH 1/2] mingw: short-circuit the conversion of `/dev/null` to UTF-16 Fcc: Sent Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit MIME-Version: 1.0 To: git@vger.kernel.org Cc: Johannes Schindelin , Junio C Hamano , Johannes Schindelin Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org From: Johannes Schindelin In the next commit, we want to disallow accessing any path that contains any segment that is equivalent to `NUL`. In particular, we want to disallow accessing `NUL` (e.g. to prevent any repository from being checked out that contains a file called `NUL`, as that is not a valid file name on Windows). However, there are legitimate use cases within Git itself to write to the Null device. As Git is really a Linux project, it does not abstract that idea, though, but instead uses `/dev/null` to describe this intention. So let's side-step the validation _specifically_ in the case that we want to write to (or read from) `/dev/null`, via a dedicated short-cut in the code that skips the call to `validate_win32_path()`. Signed-off-by: Johannes Schindelin --- compat/mingw.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) diff --git a/compat/mingw.c b/compat/mingw.c index bd24d913f9..03c4538ec8 100644 --- a/compat/mingw.c +++ b/compat/mingw.c @@ -484,16 +484,16 @@ int mingw_open (const char *filename, int oflags, ...) return -1; } - if (filename && !strcmp(filename, "/dev/null")) - filename = "nul"; - if ((oflags & O_APPEND) && !is_local_named_pipe_path(filename)) open_fn = mingw_open_append; else open_fn = _wopen; - if (xutftowcs_path(wfilename, filename) < 0) + if (filename && !strcmp(filename, "/dev/null")) + wcscpy(wfilename, L"nul"); + else if (xutftowcs_path(wfilename, filename) < 0) return -1; + fd = open_fn(wfilename, oflags, mode); if (fd < 0 && (oflags & O_ACCMODE) != O_RDONLY && errno == EACCES) { @@ -556,10 +556,13 @@ FILE *mingw_fopen (const char *filename, const char *otype) return NULL; } if (filename && !strcmp(filename, "/dev/null")) - filename = "nul"; - if (xutftowcs_path(wfilename, filename) < 0 || - xutftowcs(wotype, otype, ARRAY_SIZE(wotype)) < 0) + wcscpy(wfilename, L"nul"); + else if (xutftowcs_path(wfilename, filename) < 0) return NULL; + + if (xutftowcs(wotype, otype, ARRAY_SIZE(wotype)) < 0) + return NULL; + if (hide && !access(filename, F_OK) && set_hidden_flag(wfilename, 0)) { error("could not unhide %s", filename); return NULL; @@ -583,10 +586,13 @@ FILE *mingw_freopen (const char *filename, const char *otype, FILE *stream) return NULL; } if (filename && !strcmp(filename, "/dev/null")) - filename = "nul"; - if (xutftowcs_path(wfilename, filename) < 0 || - xutftowcs(wotype, otype, ARRAY_SIZE(wotype)) < 0) + wcscpy(wfilename, L"nul"); + else if (xutftowcs_path(wfilename, filename) < 0) return NULL; + + if (xutftowcs(wotype, otype, ARRAY_SIZE(wotype)) < 0) + return NULL; + if (hide && !access(filename, F_OK) && set_hidden_flag(wfilename, 0)) { error("could not unhide %s", filename); return NULL; -- gitgitgadget