[PATCH v7 8/9] config API: add "string" version of *_value_multi(), fix segfaults
- From
Ævar Arnfjörð Bjarmason <avarab@gmail.com>
- Date
- Mar 8, 2023, 09:06 UTC
- Message-ID
- <patch-v7-8.9-b374a716555-20230308T090513Z-avarab@gmail.com>
- In-Reply-To
- <cover-v7-0.9-00000000000-20230308T090513Z-avarab@gmail.com>
Fix numerous and mostly long-standing segfaults in consumers of the *_config_*value_multi() API. As discussed in the preceding commit an empty key in the config syntax yields a "NULL" string, which these users would give to strcmp() (or similar), resulting in segfaults.
As this change shows, most users users of the *_config_*value_multi() API didn't really want such an an unsafe and low-level API, let's give them something with the safety of git_config_get_string() instead.
This fix is similar to what the *_string() functions and others acquired in[1] and [2]. Namely introducing and using a safer "*_get_string_multi()" variant of the low-level "_*value_multi()" function.
This fixes segfaults in code introduced in:
- d811c8e17c6 (versionsort: support reorder prerelease suffixes, 2015-02-26) - c026557a373 (versioncmp: generalize version sort suffix reordering, 2016-12-08) - a086f921a72 (submodule: decouple url and submodule interest, 2017-03-17) - a6be5e6764a (log: add log.excludeDecoration config option, 2020-04-16) - 92156291ca8 (log: add default decoration filter, 2022-08-05) - 50a044f1e40 (gc: replace config subprocesses with API calls, 2022-09-27)
There are now two users ofthe low-level API:
- One in "builtin/for-each-repo.c", which we'll convert in a subsequent commit.
- The "t/helper/test-config.c" code added in [3].
As seen in the preceding commit we need to give the "t/helper/test-config.c" caller these "NULL" entries.
We could also alter the underlying git_configset_get_value_multi() function to be "string safe", but doing so would leave no room for other variants of "*_get_value_multi()" that coerce to other types.
Such coercion can't be built on the string version, since as we've established "NULL" is a true value in the boolean context, but if we coerced it to "" for use in a list of strings it'll be subsequently coerced to "false" as a boolean.
The callback pattern being used here will make it easy to introduce e.g. a "multi" variant which coerces its values to "bool", "int", "path" etc.
1. 40ea4ed9032 (Add config_error_nonbool() helper function, 2008-02-11) 2. 6c47d0e8f39 (config.c: guard config parser from value=NULL, 2008-02-11). 3. 4c715ebb96a (test-config: add tests for the config_set API, 2014-07-28)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> --- builtin/gc.c | 6 +++--- builtin/log.c | 4 ++-- config.c | 32 ++++++++++++++++++++++++++++++++ config.h | 19 +++++++++++++++++++ pack-bitmap.c | 2 +- submodule.c | 2 +- t/t4202-log.sh | 8 ++++++-- t/t5310-pack-bitmaps.sh | 8 ++++++-- t/t7004-tag.sh | 9 +++++++-- t/t7413-submodule-is-active.sh | 8 ++++++-- t/t7900-maintenance.sh | 25 ++++++++++++++++++++----- versioncmp.c | 4 ++-- 12 files changed, 105 insertions(+), 22 deletions(-)
diff --git a/builtin/gc.c b/builtin/gc.c index 2b3da377d52..9497bdf23e4 100644 --- a/builtin/gc.c +++ b/builtin/gc.c @@ -1510,7 +1510,7 @@ static int maintenance_register(int argc, const char **argv, const char *prefix) if (git_config_get("maintenance.strategy")) git_config_set("maintenance.strategy", "incremental"); - if (!git_config_get_value_multi(key, &list)) { + if (!git_config_get_string_multi(key, &list)) { for_each_string_list_item(item, list) { if (!strcmp(maintpath, item->string)) { found = 1; @@ -1578,8 +1578,8 @@ static int maintenance_unregister(int argc, const char **argv, const char *prefi git_configset_add_file(&cs, config_file); } if (!(config_file - ? git_configset_get_value_multi(&cs, key, &list) - : git_config_get_value_multi(key, &list))) { + ? git_configset_get_string_multi(&cs, key, &list) + : git_config_get_string_multi(key, &list))) { for_each_string_list_item(item, list) { if (!strcmp(maintpath, item->string)) { found = 1; diff --git a/builtin/log.c b/builtin/log.c index e43f6f9d8c1..ca847524fa4 100644 --- a/builtin/log.c +++ b/builtin/log.c @@ -184,8 +184,8 @@ static void set_default_decoration_filter(struct decoration_filter *decoration_f struct string_list *include = decoration_filter->include_ref_pattern; const struct string_list *config_exclude; - if (!git_config_get_value_multi("log.excludeDecoration", - &config_exclude)) { + if (!git_config_get_string_multi("log.excludeDecoration", + &config_exclude)) { struct string_list_item *item; for_each_string_list_item(item, config_exclude) string_list_append(decoration_filter->exclude_ref_config_pattern, diff --git a/config.c b/config.c index 569819b4a1b..c63034fb78b 100644 --- a/config.c +++ b/config.c @@ -2448,6 +2448,25 @@ int git_configset_get_value_multi(struct config_set *cs, const char *key, return 0; } +static int check_multi_string(struct string_list_item *item, void *util) +{ + return item->string ? 0 : config_error_nonbool(util); +} + +int git_configset_get_string_multi(struct config_set *cs, const char *key, + const struct string_list **dest) +{ + int ret; + + if ((ret = git_configset_get_value_multi(cs, key, dest))) + return ret; + if ((ret = for_each_string_list((struct string_list *)*dest, + check_multi_string, (void *)key))) + return ret; + + return 0; +} + int git_configset_get(struct config_set *cs, const char *key) { struct config_set_element *e; @@ -2616,6 +2635,13 @@ int repo_config_get_value_multi(struct repository *repo, const char *key, return git_configset_get_value_multi(repo->config, key, dest); } +int repo_config_get_string_multi(struct repository *repo, const char *key, + const struct string_list **dest) +{ + git_config_check_init(repo); + return git_configset_get_string_multi(repo->config, key, dest); +} + int repo_config_get_string(struct repository *repo, const char *key, char **dest) { @@ -2731,6 +2757,12 @@ int git_config_get_value_multi(const char *key, const struct string_list **dest) return repo_config_get_value_multi(the_repository, key, dest); } +int git_config_get_string_multi(const char *key, + const struct string_list **dest) +{ + return repo_config_get_string_multi(the_repository, key, dest); +} + int git_config_get_string(const char *key, char **dest) { return repo_config_get_string(the_repository, key, dest); diff --git a/config.h b/config.h index 4db6b90ac20..5f258e5b8df 100644 --- a/config.h +++ b/config.h @@ -463,6 +463,19 @@ RESULT_MUST_BE_USED int git_configset_get_value_multi(struct config_set *cs, const char *key, const struct string_list **dest); +/** + * A validation wrapper for git_configset_get_value_multi() which does + * for it what git_configset_get_string() does for + * git_configset_get_value(). + * + * The configuration syntax allows for "[section] key", which will + * give us a NULL entry in the "struct string_list", as opposed to + * "[section] key =" which is the empty string. Most users of the API + * are not prepared to handle NULL in a "struct string_list". + */ +int git_configset_get_string_multi(struct config_set *cs, const char *key, + const struct string_list **dest); + /** * Clears `config_set` structure, removes all saved variable-value pairs. */ @@ -509,6 +522,9 @@ int repo_config_get_value(struct repository *repo, RESULT_MUST_BE_USED int repo_config_get_value_multi(struct repository *repo, const char *key, const struct string_list **dest); +RESULT_MUST_BE_USED +int repo_config_get_string_multi(struct repository *repo, const char *key, + const struct string_list **dest); int repo_config_get_string(struct repository *repo, const char *key, char **dest); int repo_config_get_string_tmp(struct repository *repo, @@ -570,6 +586,9 @@ int git_config_get_value(const char *key, const char **value); RESULT_MUST_BE_USED int git_config_get_value_multi(const char *key, const struct string_list **dest); +RESULT_MUST_BE_USED +int git_config_get_string_multi(const char *key, + const struct string_list **dest); /** * Resets and invalidates the config cache. diff --git a/pack-bitmap.c b/pack-bitmap.c index 15c5eb507c0..d003c7e60b4 100644 --- a/pack-bitmap.c +++ b/pack-bitmap.c @@ -2316,7 +2316,7 @@ const struct string_list *bitmap_preferred_tips(struct repository *r) { const struct string_list *dest; - if (!repo_config_get_value_multi(r, "pack.preferbitmaptips", &dest)) + if (!repo_config_get_string_multi(r, "pack.preferbitmaptips", &dest)) return dest; return NULL; } diff --git a/submodule.c b/submodule.c index 4b6f5223b0c..30a103246ec 100644 --- a/submodule.c +++ b/submodule.c @@ -274,7 +274,7 @@ int is_tree_submodule_active(struct repository *repo, free(key); /* submodule.active is set */ - if (!repo_config_get_value_multi(repo, "submodule.active", &sl)) { + if (!repo_config_get_string_multi(repo, "submodule.active", &sl)) { struct pathspec ps; struct strvec args = STRVEC_INIT; const struct string_list_item *item; diff --git a/t/t4202-log.sh b/t/t4202-log.sh index e4f02d8208b..ae73aef922f 100755 --- a/t/t4202-log.sh +++ b/t/t4202-log.sh @@ -835,7 +835,7 @@ test_expect_success 'log.decorate configuration' ' ' -test_expect_failure 'parse log.excludeDecoration with no value' ' +test_expect_success 'parse log.excludeDecoration with no value' ' cp .git/config .git/config.orig && test_when_finished mv .git/config.orig .git/config && @@ -843,7 +843,11 @@ test_expect_failure 'parse log.excludeDecoration with no value' ' [log] excludeDecoration EOF - git log --decorate=short + cat >expect <<-\EOF && + error: missing value for '\''log.excludeDecoration'\'' + EOF + git log --decorate=short 2>actual && + test_cmp expect actual ' test_expect_success 'decorate-refs with glob' ' diff --git a/t/t5310-pack-bitmaps.sh b/t/t5310-pack-bitmaps.sh index 0306b399188..526a5a506eb 100755 --- a/t/t5310-pack-bitmaps.sh +++ b/t/t5310-pack-bitmaps.sh @@ -404,7 +404,7 @@ test_bitmap_cases () { ) ' - test_expect_failure 'pack.preferBitmapTips' ' + test_expect_success 'pack.preferBitmapTips' ' git init repo && test_when_finished "rm -rf repo" && ( @@ -416,7 +416,11 @@ test_bitmap_cases () { [pack] preferBitmapTips EOF - git repack -adb + cat >expect <<-\EOF && + error: missing value for '\''pack.preferbitmaptips'\'' + EOF + git repack -adb 2>actual && + test_cmp expect actual ) ' diff --git a/t/t7004-tag.sh b/t/t7004-tag.sh index f343551a7d4..f4a31ada79a 100755 --- a/t/t7004-tag.sh +++ b/t/t7004-tag.sh @@ -1843,7 +1843,7 @@ test_expect_success 'invalid sort parameter in configuratoin' ' test_must_fail git tag -l "foo*" ' -test_expect_failure 'version sort handles empty value for versionsort.{prereleaseSuffix,suffix}' ' +test_expect_success 'version sort handles empty value for versionsort.{prereleaseSuffix,suffix}' ' cp .git/config .git/config.orig && test_when_finished mv .git/config.orig .git/config && @@ -1852,7 +1852,12 @@ test_expect_failure 'version sort handles empty value for versionsort.{prereleas prereleaseSuffix suffix EOF - git tag -l --sort=version:refname + cat >expect <<-\EOF && + error: missing value for '\''versionsort.suffix'\'' + error: missing value for '\''versionsort.prereleasesuffix'\'' + EOF + git tag -l --sort=version:refname 2>actual && + test_cmp expect actual ' test_expect_success 'version sort with prerelease reordering' ' diff --git a/t/t7413-submodule-is-active.sh b/t/t7413-submodule-is-active.sh index bfe27e50732..887d181b72e 100755 --- a/t/t7413-submodule-is-active.sh +++ b/t/t7413-submodule-is-active.sh @@ -51,7 +51,7 @@ test_expect_success 'is-active works with submodule.<name>.active config' ' test-tool -C super submodule is-active sub1 ' -test_expect_failure 'is-active handles submodule.active config missing a value' ' +test_expect_success 'is-active handles submodule.active config missing a value' ' cp super/.git/config super/.git/config.orig && test_when_finished mv super/.git/config.orig super/.git/config && @@ -60,7 +60,11 @@ test_expect_failure 'is-active handles submodule.active config missing a value' active EOF - test-tool -C super submodule is-active sub1 + cat >expect <<-\EOF && + error: missing value for '\''submodule.active'\'' + EOF + test-tool -C super submodule is-active sub1 2>actual && + test_cmp expect actual ' test_expect_success 'is-active works with basic submodule.active config' ' diff --git a/t/t7900-maintenance.sh b/t/t7900-maintenance.sh index d82eac6a471..487e326b3fa 100755 --- a/t/t7900-maintenance.sh +++ b/t/t7900-maintenance.sh @@ -524,7 +524,7 @@ test_expect_success 'register and unregister' ' git maintenance unregister --config-file ./other --force ' -test_expect_failure 'register with no value for maintenance.repo' ' +test_expect_success 'register with no value for maintenance.repo' ' cp .git/config .git/config.orig && test_when_finished mv .git/config.orig .git/config && @@ -532,10 +532,15 @@ test_expect_failure 'register with no value for maintenance.repo' ' [maintenance] repo EOF - git maintenance register + cat >expect <<-\EOF && + error: missing value for '\''maintenance.repo'\'' + EOF + git maintenance register 2>actual && + test_cmp expect actual && + git config maintenance.repo ' -test_expect_failure 'unregister with no value for maintenance.repo' ' +test_expect_success 'unregister with no value for maintenance.repo' ' cp .git/config .git/config.orig && test_when_finished mv .git/config.orig .git/config && @@ -543,8 +548,18 @@ test_expect_failure 'unregister with no value for maintenance.repo' ' [maintenance] repo EOF - git maintenance unregister && - git maintenance unregister --force + cat >expect <<-\EOF && + error: missing value for '\''maintenance.repo'\'' + EOF + test_expect_code 128 git maintenance unregister 2>actual.raw && + grep ^error actual.raw >actual && + test_cmp expect actual && + git config maintenance.repo && + + git maintenance unregister --force 2>actual.raw && + grep ^error actual.raw >actual && + test_cmp expect actual && + git config maintenance.repo ' test_expect_success !MINGW 'register and unregister with regex metacharacters' ' diff --git a/versioncmp.c b/versioncmp.c index 60c3a517122..7498da96e0e 100644 --- a/versioncmp.c +++ b/versioncmp.c @@ -164,8 +164,8 @@ int versioncmp(const char *s1, const char *s2) const char *const oldk = "versionsort.prereleasesuffix"; const struct string_list *newl; const struct string_list *oldl; - int new = git_config_get_value_multi(newk, &newl); - int old = git_config_get_value_multi(oldk, &oldl); + int new = git_config_get_string_multi(newk, &newl); + int old = git_config_get_string_multi(oldk, &oldl); if (!new && !old) warning("ignoring %s because %s is set", oldk, newk);
-- 2.40.0.rc1.1034.g5867a1b10c5