[PATCH v2] maintenance --unregister: fix uninit'd data use & -Wdeclaration-after-statement
Since (maintenance: add option to register in a specific config, 2022-11-09) we've been unable to build with "DEVELOPER=1" without "DEVOPTS=no-error", as the added code triggers a "-Wdeclaration-after-statement" warning.
And worse than that, the data handed to git_configset_clear() is uninitialized, as can be spotted with e.g.:
./t7900-maintenance.sh -vixd --run=23 --valgrind
[...]
+ git maintenance unregister --force
Conditional jump or move depends on uninitialised value(s)
at 0x6B5F1E: git_configset_clear (config.c:2367)
by 0x4BA64E: maintenance_unregister (gc.c:1619)
by 0x4BD278: cmd_maintenance (gc.c:2650)
by 0x409905: run_builtin (git.c:466)
by 0x40A21C: handle_builtin (git.c:721)
by 0x40A58E: run_argv (git.c:788)
by 0x40AF68: cmd_main (git.c:926)
by 0x5D39FE: main (common-main.c:57)
Uninitialised value was created by a stack allocation
at 0x4BA22C: maintenance_unregister (gc.c:1557)
Let's fix both of these issues, and also move the scope of the variable to the "if" statement it's used in, to make it obvious where it's used.
Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
Range-diff against v1:
1: 54d405f15f1 ! 1: f37e99c9d59 builtin/gc.c: fix -Wdeclaration-after-statement
@@ Metadata
Author: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
## Commit message ##
- builtin/gc.c: fix -Wdeclaration-after-statement
+ maintenance --unregister: fix uninit'd data use & -Wdeclaration-after-statement
- In 1f80129d61b (maintenance: add option to register in a specific
- config, 2022-11-09) code was added which triggers a
- "-Wdeclaration-after-statement" warning, which is on by default with
- DEVELOPER=1.
+ Since (maintenance: add option to register in a specific config,
+ 2022-11-09) we've been unable to build with "DEVELOPER=1" without
+ "DEVOPTS=no-error", as the added code triggers a
+ "-Wdeclaration-after-statement" warning.
+ And worse than that, the data handed to git_configset_clear() is
+ uninitialized, as can be spotted with e.g.:
+
+ ./t7900-maintenance.sh -vixd --run=23 --valgrind
+ [...]
+ + git maintenance unregister --force
+ Conditional jump or move depends on uninitialised value(s)
+ at 0x6B5F1E: git_configset_clear (config.c:2367)
+ by 0x4BA64E: maintenance_unregister (gc.c:1619)
+ by 0x4BD278: cmd_maintenance (gc.c:2650)
+ by 0x409905: run_builtin (git.c:466)
+ by 0x40A21C: handle_builtin (git.c:721)
+ by 0x40A58E: run_argv (git.c:788)
+ by 0x40AF68: cmd_main (git.c:926)
+ by 0x5D39FE: main (common-main.c:57)
+ Uninitialised value was created by a stack allocation
+ at 0x4BA22C: maintenance_unregister (gc.c:1557)
+
+ Let's fix both of these issues, and also move the scope of the
+ variable to the "if" statement it's used in, to make it obvious where
+ it's used.
+
+ Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
## builtin/gc.c ##
-@@ builtin/gc.c: static int maintenance_unregister(int argc, const char **argv, const char *prefi
- int found = 0;
- struct string_list_item *item;
- const struct string_list *list;
-+ struct config_set cs;
-
- argc = parse_options(argc, argv, prefix, options,
- builtin_maintenance_unregister_usage, 0);
@@ builtin/gc.c: static int maintenance_unregister(int argc, const char **argv, const char *prefi
usage_with_options(builtin_maintenance_unregister_usage,
options);
- struct config_set cs;
if (config_file) {
++ struct config_set cs;
++
git_configset_init(&cs);
git_configset_add_file(&cs, config_file);
+ list = git_configset_get_value_multi(&cs, key);
++ git_configset_clear(&cs);
+ } else {
+ list = git_config_get_value_multi(key);
+ }
+@@ builtin/gc.c: static int maintenance_unregister(int argc, const char **argv, const char *prefi
+ die(_("repository '%s' is not registered"), maintpath);
+ }
+
+- git_configset_clear(&cs);
+ free(maintpath);
+ return 0;
+ } builtin/gc.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
Show changes to builtin/gc.c +3 −2
diff --git a/builtin/gc.c b/builtin/gc.c
index 56b107e7f0b..d87cf84041f 100644
--- a/builtin/gc.c
+++ b/builtin/gc.c
@@ -1550,11 +1550,13 @@ static int maintenance_unregister(int argc, const char **argv, const char *prefi
usage_with_options(builtin_maintenance_unregister_usage,
options);
- struct config_set cs;
if (config_file) {
+ struct config_set cs;
+
git_configset_init(&cs);
git_configset_add_file(&cs, config_file);
list = git_configset_get_value_multi(&cs, key);
+ git_configset_clear(&cs);
} else {
list = git_config_get_value_multi(key);
}
@@ -1590,7 +1592,6 @@ static int maintenance_unregister(int argc, const char **argv, const char *prefi
die(_("repository '%s' is not registered"), maintpath);
}
- git_configset_clear(&cs);
free(maintpath);
return 0;
}
--
2.38.0.1473.g172bcc0511c
Ævar Arnfjörð Bjarmason
