config API: add "string" version of *_value_multi(), fix segfaults
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> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Ævar Arnfjörð Bjarmason committed
Mar 28, 2023 at 16:04 UTC
9e2d884d0fcf0631164c33d458a251bee6053bb1
12 files changed
+105
-22
builtin/gc.c
+3
-3
@@ -1510,7 +1510,7 @@ static int maintenance_register(int argc, const char **argv, const char *prefix)
1510
if (git_config_get("maintenance.strategy"))
1511
git_config_set("maintenance.strategy", "incremental");
1512
1513
- if (!git_config_get_value_multi(key, &list)) {
1513
+ if (!git_config_get_string_multi(key, &list)) {
1514
for_each_string_list_item(item, list) {
1515
if (!strcmp(maintpath, item->string)) {
1516
found = 1;
@@ -1578,8 +1578,8 @@ static int maintenance_unregister(int argc, const char **argv, const char *prefi
1578
git_configset_add_file(&cs, config_file);
1579
}
1580
if (!(config_file
1581
- ? git_configset_get_value_multi(&cs, key, &list)
1582
- : git_config_get_value_multi(key, &list))) {
1581
+ ? git_configset_get_string_multi(&cs, key, &list)
1582
+ : git_config_get_string_multi(key, &list))) {
1583
for_each_string_list_item(item, list) {
1584
if (!strcmp(maintpath, item->string)) {
1585
found = 1;
builtin/log.c
+2
-2
@@ -184,8 +184,8 @@ static void set_default_decoration_filter(struct decoration_filter *decoration_f
184
struct string_list *include = decoration_filter->include_ref_pattern;
185
const struct string_list *config_exclude;
186
187
- if (!git_config_get_value_multi("log.excludeDecoration",
188
- &config_exclude)) {
187
+ if (!git_config_get_string_multi("log.excludeDecoration",
188
+ &config_exclude)) {
189
struct string_list_item *item;
190
for_each_string_list_item(item, config_exclude)
191
string_list_append(decoration_filter->exclude_ref_config_pattern,
config.c
+32
@@ -2434,6 +2434,25 @@ int git_configset_get_value_multi(struct config_set *cs, const char *key,
2434
return 0;
2435
}
2436
2437
+static int check_multi_string(struct string_list_item *item, void *util)
2438
+{
2439
+ return item->string ? 0 : config_error_nonbool(util);
2440
+}
2441
+
2442
+int git_configset_get_string_multi(struct config_set *cs, const char *key,
2443
+ const struct string_list **dest)
2444
+{
2445
+ int ret;
2446
+
2447
+ if ((ret = git_configset_get_value_multi(cs, key, dest)))
2448
+ return ret;
2449
+ if ((ret = for_each_string_list((struct string_list *)*dest,
2450
+ check_multi_string, (void *)key)))
2451
+ return ret;
2452
+
2453
+ return 0;
2454
+}
2455
+
2456
int git_configset_get(struct config_set *cs, const char *key)
2457
{
2458
struct config_set_element *e;
@@ -2602,6 +2621,13 @@ int repo_config_get_value_multi(struct repository *repo, const char *key,
2621
return git_configset_get_value_multi(repo->config, key, dest);
2622
}
2623
2624
+int repo_config_get_string_multi(struct repository *repo, const char *key,
2625
+ const struct string_list **dest)
2626
+{
2627
+ git_config_check_init(repo);
2628
+ return git_configset_get_string_multi(repo->config, key, dest);
2629
+}
2630
+
2631
int repo_config_get_string(struct repository *repo,
2632
const char *key, char **dest)
2633
{
@@ -2717,6 +2743,12 @@ int git_config_get_value_multi(const char *key, const struct string_list **dest)
2743
return repo_config_get_value_multi(the_repository, key, dest);
2744
}
2745
2746
+int git_config_get_string_multi(const char *key,
2747
+ const struct string_list **dest)
2748
+{
2749
+ return repo_config_get_string_multi(the_repository, key, dest);
2750
+}
2751
+
2752
int git_config_get_string(const char *key, char **dest)
2753
{
2754
return repo_config_get_string(the_repository, key, dest);
config.h
+19
@@ -472,6 +472,19 @@ RESULT_MUST_BE_USED
472
int git_configset_get_value_multi(struct config_set *cs, const char *key,
473
const struct string_list **dest);
474
475
+/**
476
+ * A validation wrapper for git_configset_get_value_multi() which does
477
+ * for it what git_configset_get_string() does for
478
+ * git_configset_get_value().
479
+ *
480
+ * The configuration syntax allows for "[section] key", which will
481
+ * give us a NULL entry in the "struct string_list", as opposed to
482
+ * "[section] key =" which is the empty string. Most users of the API
483
+ * are not prepared to handle NULL in a "struct string_list".
484
+ */
485
+int git_configset_get_string_multi(struct config_set *cs, const char *key,
486
+ const struct string_list **dest);
487
+
488
/**
489
* Clears `config_set` structure, removes all saved variable-value pairs.
490
*/
@@ -522,6 +535,9 @@ int repo_config_get_value(struct repository *repo,
535
RESULT_MUST_BE_USED
536
int repo_config_get_value_multi(struct repository *repo, const char *key,
537
const struct string_list **dest);
538
+RESULT_MUST_BE_USED
539
+int repo_config_get_string_multi(struct repository *repo, const char *key,
540
+ const struct string_list **dest);
541
int repo_config_get_string(struct repository *repo,
542
const char *key, char **dest);
543
int repo_config_get_string_tmp(struct repository *repo,
@@ -583,6 +599,9 @@ int git_config_get_value(const char *key, const char **value);
599
RESULT_MUST_BE_USED
600
int git_config_get_value_multi(const char *key,
601
const struct string_list **dest);
602
+RESULT_MUST_BE_USED
603
+int git_config_get_string_multi(const char *key,
604
+ const struct string_list **dest);
605
606
/**
607
* Resets and invalidates the config cache.
pack-bitmap.c
+1
-1
@@ -2303,7 +2303,7 @@ const struct string_list *bitmap_preferred_tips(struct repository *r)
2303
{
2304
const struct string_list *dest;
2305
2306
- if (!repo_config_get_value_multi(r, "pack.preferbitmaptips", &dest))
2306
+ if (!repo_config_get_string_multi(r, "pack.preferbitmaptips", &dest))
2307
return dest;
2308
return NULL;
2309
}
submodule.c
+1
-1
@@ -274,7 +274,7 @@ int is_tree_submodule_active(struct repository *repo,
274
free(key);
275
276
/* submodule.active is set */
277
- if (!repo_config_get_value_multi(repo, "submodule.active", &sl)) {
277
+ if (!repo_config_get_string_multi(repo, "submodule.active", &sl)) {
278
struct pathspec ps;
279
struct strvec args = STRVEC_INIT;
280
const struct string_list_item *item;
t/t4202-log.sh
+6
-2
@@ -835,7 +835,7 @@ test_expect_success 'log.decorate configuration' '
835
836
'
837
838
-test_expect_failure 'parse log.excludeDecoration with no value' '
838
+test_expect_success 'parse log.excludeDecoration with no value' '
839
cp .git/config .git/config.orig &&
840
test_when_finished mv .git/config.orig .git/config &&
841
@@ -843,7 +843,11 @@ test_expect_failure 'parse log.excludeDecoration with no value' '
843
[log]
844
excludeDecoration
845
EOF
846
- git log --decorate=short
846
+ cat >expect <<-\EOF &&
847
+ error: missing value for '\''log.excludeDecoration'\''
848
+ EOF
849
+ git log --decorate=short 2>actual &&
850
+ test_cmp expect actual
851
'
852
853
test_expect_success 'decorate-refs with glob' '
t/t5310-pack-bitmaps.sh
+6
-2
@@ -404,7 +404,7 @@ test_bitmap_cases () {
404
)
405
'
406
407
- test_expect_failure 'pack.preferBitmapTips' '
407
+ test_expect_success 'pack.preferBitmapTips' '
408
git init repo &&
409
test_when_finished "rm -rf repo" &&
410
(
@@ -416,7 +416,11 @@ test_bitmap_cases () {
416
[pack]
417
preferBitmapTips
418
EOF
419
- git repack -adb
419
+ cat >expect <<-\EOF &&
420
+ error: missing value for '\''pack.preferbitmaptips'\''
421
+ EOF
422
+ git repack -adb 2>actual &&
423
+ test_cmp expect actual
424
)
425
'
426
t/t7004-tag.sh
+7
-2
@@ -1843,7 +1843,7 @@ test_expect_success 'invalid sort parameter in configuratoin' '
1843
test_must_fail git tag -l "foo*"
1844
'
1845
1846
-test_expect_failure 'version sort handles empty value for versionsort.{prereleaseSuffix,suffix}' '
1846
+test_expect_success 'version sort handles empty value for versionsort.{prereleaseSuffix,suffix}' '
1847
cp .git/config .git/config.orig &&
1848
test_when_finished mv .git/config.orig .git/config &&
1849
@@ -1852,7 +1852,12 @@ test_expect_failure 'version sort handles empty value for versionsort.{prereleas
1852
prereleaseSuffix
1853
suffix
1854
EOF
1855
- git tag -l --sort=version:refname
1855
+ cat >expect <<-\EOF &&
1856
+ error: missing value for '\''versionsort.suffix'\''
1857
+ error: missing value for '\''versionsort.prereleasesuffix'\''
1858
+ EOF
1859
+ git tag -l --sort=version:refname 2>actual &&
1860
+ test_cmp expect actual
1861
'
1862
1863
test_expect_success 'version sort with prerelease reordering' '
t/t7413-submodule-is-active.sh
+6
-2
@@ -51,7 +51,7 @@ test_expect_success 'is-active works with submodule.<name>.active config' '
51
test-tool -C super submodule is-active sub1
52
'
53
54
-test_expect_failure 'is-active handles submodule.active config missing a value' '
54
+test_expect_success 'is-active handles submodule.active config missing a value' '
55
cp super/.git/config super/.git/config.orig &&
56
test_when_finished mv super/.git/config.orig super/.git/config &&
57
@@ -60,7 +60,11 @@ test_expect_failure 'is-active handles submodule.active config missing a value'
60
active
61
EOF
62
63
- test-tool -C super submodule is-active sub1
63
+ cat >expect <<-\EOF &&
64
+ error: missing value for '\''submodule.active'\''
65
+ EOF
66
+ test-tool -C super submodule is-active sub1 2>actual &&
67
+ test_cmp expect actual
68
'
69
70
test_expect_success 'is-active works with basic submodule.active config' '
t/t7900-maintenance.sh
+20
-5
@@ -524,7 +524,7 @@ test_expect_success 'register and unregister' '
524
git maintenance unregister --config-file ./other --force
525
'
526
527
-test_expect_failure 'register with no value for maintenance.repo' '
527
+test_expect_success 'register with no value for maintenance.repo' '
528
cp .git/config .git/config.orig &&
529
test_when_finished mv .git/config.orig .git/config &&
530
@@ -532,10 +532,15 @@ test_expect_failure 'register with no value for maintenance.repo' '
532
[maintenance]
533
repo
534
EOF
535
- git maintenance register
535
+ cat >expect <<-\EOF &&
536
+ error: missing value for '\''maintenance.repo'\''
537
+ EOF
538
+ git maintenance register 2>actual &&
539
+ test_cmp expect actual &&
540
+ git config maintenance.repo
541
'
542
538
-test_expect_failure 'unregister with no value for maintenance.repo' '
543
+test_expect_success 'unregister with no value for maintenance.repo' '
544
cp .git/config .git/config.orig &&
545
test_when_finished mv .git/config.orig .git/config &&
546
@@ -543,8 +548,18 @@ test_expect_failure 'unregister with no value for maintenance.repo' '
548
[maintenance]
549
repo
550
EOF
546
- git maintenance unregister &&
547
- git maintenance unregister --force
551
+ cat >expect <<-\EOF &&
552
+ error: missing value for '\''maintenance.repo'\''
553
+ EOF
554
+ test_expect_code 128 git maintenance unregister 2>actual.raw &&
555
+ grep ^error actual.raw >actual &&
556
+ test_cmp expect actual &&
557
+ git config maintenance.repo &&
558
+
559
+ git maintenance unregister --force 2>actual.raw &&
560
+ grep ^error actual.raw >actual &&
561
+ test_cmp expect actual &&
562
+ git config maintenance.repo
563
'
564
565
test_expect_success !MINGW 'register and unregister with regex metacharacters' '
versioncmp.c
+2
-2
@@ -164,8 +164,8 @@ int versioncmp(const char *s1, const char *s2)
164
const char *const oldk = "versionsort.prereleasesuffix";
165
const struct string_list *newl;
166
const struct string_list *oldl;
167
- int new = git_config_get_value_multi(newk, &newl);
168
- int old = git_config_get_value_multi(oldk, &oldl);
167
+ int new = git_config_get_string_multi(newk, &newl);
168
+ int old = git_config_get_string_multi(oldk, &oldl);
169
170
if (!new && !old)
171
warning("ignoring %s because %s is set", oldk, newk);