From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by dcvr.yhbt.net (Postfix) with ESMTP id 2438B1F9FF for ; Thu, 18 Mar 2021 18:45:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232784AbhCRSoR (ORCPT ); Thu, 18 Mar 2021 14:44:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53894 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232651AbhCRSoA (ORCPT ); Thu, 18 Mar 2021 14:44:00 -0400 Received: from mail-qk1-x735.google.com (mail-qk1-x735.google.com [IPv6:2607:f8b0:4864:20::735]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6047EC06174A for ; Thu, 18 Mar 2021 11:44:00 -0700 (PDT) Received: by mail-qk1-x735.google.com with SMTP id 7so257849qka.7 for ; Thu, 18 Mar 2021 11:44:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=usp.br; s=usp-google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=EsyJct5pdX+o9U4JQQNixI3MfxW3aIgT78If7CNyjZo=; b=f6fSvAsaiZE6FdLNfjdrgbAi6IAdyNqIy53lJ3tfbh3Ujb2mfV20aWxPH7JPuUFTvJ RCZyDo0SZA+6hprYCm6pReQhL+VSdAFhn/kILdQ3bcInxPbRtkkHgKOIPhVu9QAssxvY ejEGbequuZomlrctw3jdfiuDojUe9mNNVms+KqNBQmkGTf3vE6wbGTONIqPToCqjVXkz PXRhqcoR4xHC/e1zuU+MUii7tkVNf8fXGaGqWETjNfXwkDGBZNXD/acA6oInHTIIxlXv 4G+UsjcXlAis4BCN0PdaZaeaQ+7srp/nDiITFBNvb0Azqsy+ZzuLV0APdLUmtUBAG/MO n9GQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=EsyJct5pdX+o9U4JQQNixI3MfxW3aIgT78If7CNyjZo=; b=lXK/Te4yUwk0am2tbW4pH2UFN/ZyTxurDmUtt2o7w3jB2JsrA+82rlF/rhMl+G/JL5 5aHk9QcfFQhr+kcunIz1I1Mveon29dqRdGjZNO+QyHX8RXWIFeOD35VC4f5hlxh8OGjr WCy/Ok953dBJzxiGXfp8RCY7HbGbE9gjXDILDSwSVk6Ye+Qjn+kVrfWHq33mh/5Lk3Nu E1RazYuPyg5kGQYF0X1rB6BKNWk7+V71BtAZT0zvONLmU8hx0Op/Jlqx3ayoqqKed9Op onteCpRTSzE4SZgqO2STRUR5XJhGTIIrxtcUMvBbJ0LudqlFq2RiuLC41Elysjy3rLxE dTEQ== X-Gm-Message-State: AOAM533TJ16Tc8C92mdYhKgp/x8o7zKVo+Mj0x6IoobEA9cxPYocgDcy yrUMCkikjzzSKXGr0oaW0/bsyEhlwKNvBQ== X-Google-Smtp-Source: ABdhPJxxApUaO3fp5RvIBMujxT3ozUdP6nP4UD3s4nAVLU6LPcRz7u1N5LnNlIahgLMqfolhQXa8zQ== X-Received: by 2002:a05:620a:214a:: with SMTP id m10mr5997292qkm.372.1616093039114; Thu, 18 Mar 2021 11:43:59 -0700 (PDT) Received: from mango.meuintelbras.local ([177.32.118.149]) by smtp.gmail.com with ESMTPSA id f9sm2037324qto.46.2021.03.18.11.43.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 18 Mar 2021 11:43:58 -0700 (PDT) From: Matheus Tavares To: git@vger.kernel.org Cc: Johannes.Schindelin@gmx.de Subject: [PATCH 2/2] checkout: don't follow symlinks when removing entries Date: Thu, 18 Mar 2021 15:43:47 -0300 Message-Id: X-Mailer: git-send-email 2.30.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org At 1d718a5108 ("do not overwrite untracked symlinks", 2011-02-20), symlink.c:check_leading_path() started returning different codes for FL_ENOENT and FL_SYMLINK. But one of its callers, unlink_entry(), was not adjusted for this change, so it started to follow symlinks on the leading path of to-be-removed entries. Fix that and add a regression test. Note that since 1d718a5108 check_leading_path() no longer differentiates the case where it found a symlink in the path's leading components from the cases where it found a regular file or failed to lstat() the component. So, a side effect of this current patch is that unlink_entry() now returns early in all of these three cases. And because we no longer try to unlink such paths, we also don't get the warning from remove_or_warn(). For the regular file and symlink cases, it's questionable whether the warning was useful in the first place: unlink_entry() removes tracked paths that should no longer be present in the state we are checking out to. If the path had its leading dir replaced by another file, it means that the basename already doesn't exist, so there is no need for a warning. Sure, we are leaving a regular file or symlink behind at the path's dirname, but this file is either untracked now (so again, no need to warn), or it will be replaced by a tracked file during the next phase of this checkout operation. As for failing to lstat() one of the leading components, the basename might still exist only we cannot unlink it (e.g. due to the lack of the required permissions). Since the user expect it to be removed (especially with checkout's --no-overlay option), add back the warning in this more relevant case. Signed-off-by: Matheus Tavares --- cache.h | 2 +- entry.c | 2 +- symlinks.c | 30 ++++++++++++++++++++++-------- t/t2021-checkout-overwrite.sh | 12 ++++++++++++ unpack-trees.c | 2 +- 5 files changed, 37 insertions(+), 11 deletions(-) diff --git a/cache.h b/cache.h index 6fda8091f1..4f0b29bfe4 100644 --- a/cache.h +++ b/cache.h @@ -1659,7 +1659,7 @@ static inline void cache_def_clear(struct cache_def *cache) int has_symlink_leading_path(const char *name, int len); int threaded_has_symlink_leading_path(struct cache_def *, const char *, int); -int check_leading_path(const char *name, int len); +int check_leading_path(const char *name, int len, int warn_on_lstat_err); int has_dirs_only_path(const char *name, int len, int prefix_len); void invalidate_lstat_cache(void); void schedule_dir_for_removal(const char *name, int len); diff --git a/entry.c b/entry.c index 7b9f43716f..33ce80ca91 100644 --- a/entry.c +++ b/entry.c @@ -530,7 +530,7 @@ void unlink_entry(const struct cache_entry *ce) submodule_move_head(ce->name, "HEAD", NULL, SUBMODULE_MOVE_HEAD_FORCE); } - if (!check_leading_path(ce->name, ce_namelen(ce))) + if (check_leading_path(ce->name, ce_namelen(ce), 1) >= 0) return; if (remove_or_warn(ce->ce_mode, ce->name)) return; diff --git a/symlinks.c b/symlinks.c index fbccd340f0..5232d02020 100644 --- a/symlinks.c +++ b/symlinks.c @@ -1,6 +1,7 @@ #include "cache.h" -static int threaded_check_leading_path(struct cache_def *cache, const char *name, int len); +static int threaded_check_leading_path(struct cache_def *cache, const char *name, + int len, int warn_on_lstat_err); static int threaded_has_dirs_only_path(struct cache_def *cache, const char *name, int len, int prefix_len); /* @@ -72,7 +73,7 @@ static int lstat_cache_matchlen(struct cache_def *cache, int prefix_len_stat_func) { int match_len, last_slash, last_slash_dir, previous_slash; - int save_flags, ret; + int save_flags, ret, saved_errno = 0; struct stat st; if (cache->track_flags != track_flags || @@ -139,6 +140,7 @@ static int lstat_cache_matchlen(struct cache_def *cache, if (ret) { *ret_flags = FL_LSTATERR; + saved_errno = errno; if (errno == ENOENT) *ret_flags |= FL_NOENT; } else if (S_ISDIR(st.st_mode)) { @@ -180,6 +182,8 @@ static int lstat_cache_matchlen(struct cache_def *cache, } else { reset_lstat_cache(cache); } + if (saved_errno) + errno = saved_errno; return match_len; } @@ -207,9 +211,10 @@ int has_symlink_leading_path(const char *name, int len) return threaded_has_symlink_leading_path(&default_cache, name, len); } -int check_leading_path(const char *name, int len) +int check_leading_path(const char *name, int len, int warn_on_lstat_err) { - return threaded_check_leading_path(&default_cache, name, len); + return threaded_check_leading_path(&default_cache, name, len, + warn_on_lstat_err); } /* @@ -218,19 +223,28 @@ int check_leading_path(const char *name, int len) * Return -1 if leading path exists and is a directory. * * Return the length of a leading component if it either exists but it's not a - * directory, or if we were unable to lstat() it. + * directory, or if we were unable to lstat() it. If warn_on_lstat_err is true, + * also emit a warning for this error. */ -static int threaded_check_leading_path(struct cache_def *cache, const char *name, int len) +static int threaded_check_leading_path(struct cache_def *cache, const char *name, + int len, int warn_on_lstat_err) { int flags; int match_len = lstat_cache_matchlen(cache, name, len, &flags, FL_SYMLINK|FL_NOENT|FL_DIR, USE_ONLY_LSTAT); + int saved_errno = errno; + if (flags & FL_NOENT) return 0; else if (flags & FL_DIR) return -1; - else - return match_len; + if (warn_on_lstat_err && (flags & FL_LSTATERR)) { + char *path = xmemdupz(name, match_len); + errno = saved_errno; + warning_errno(_("failed to lstat '%s'"), path); + free(path); + } + return match_len; } int has_dirs_only_path(const char *name, int len, int prefix_len) diff --git a/t/t2021-checkout-overwrite.sh b/t/t2021-checkout-overwrite.sh index c2ada7de37..70d69263e6 100755 --- a/t/t2021-checkout-overwrite.sh +++ b/t/t2021-checkout-overwrite.sh @@ -51,4 +51,16 @@ test_expect_success SYMLINKS 'the symlink remained' ' test -h a/b ' +test_expect_success SYMLINKS 'checkout -f must not follow symlinks when removing entries' ' + git checkout -f start && + mkdir dir && + >dir/f && + git add dir/f && + git commit -m "add dir/f" && + mv dir untracked && + ln -s untracked dir && + git checkout -f HEAD~ && + test_path_is_file untracked/f +' + test_done diff --git a/unpack-trees.c b/unpack-trees.c index eb8fcda31b..ed0db8031d 100644 --- a/unpack-trees.c +++ b/unpack-trees.c @@ -2097,7 +2097,7 @@ static int verify_absent_1(const struct cache_entry *ce, if (o->index_only || o->reset || !o->update) return 0; - len = check_leading_path(ce->name, ce_namelen(ce)); + len = check_leading_path(ce->name, ce_namelen(ce), 0); if (!len) return 0; else if (len > 0) { -- 2.30.1