[PATCH v2 03/19] global: convert intentionally-leaking config strings to consts
- From
Patrick Steinhardt <ps@pks.im>
- Date
- May 30, 2024, 12:50 UTC
- Message-ID
- <8b71dfa208c14600e4f9164017acda10627ba70a.1717073346.git.ps@pks.im>
- In-Reply-To
- <cover.1717073346.git.ps@pks.im>
There are multiple cases where we intentionally leak config strings:
- `struct gpg_format` is used to track programs that can be used for
signing commits, either via gpg(1), gpgsm(1) or ssh-keygen(1). The
user can override the commands via several config variables. As the
array is populated once, only, and will never be free'd, it is fine
to treat the program as a quasi-constant. - `struct ll_merge_driver` is used to track merge drivers. Same as
with the GPG format, these drivers are populated once and then
reused. Its data is never free'd, either. - `struct userdiff_funcname` and `struct userdiff_driver` can be
configured via `diff.<driver>.*` to add additional drivers. Again,
these have a global lifetime and are never free'd.All of these are intentionally kept alive and never free'd. Furthermore, all of these are being assigned both string constants in some places, and allocated strings in other places. This will cause warnings once we enable `-Wwrite-strings`, so let's mark the respective fields as `const char *` and cast away the constness when assigning those values.
Signed-off-by: Patrick Steinhardt <ps@pks.im> --- gpg-interface.c | 4 ++-- merge-ll.c | 11 ++++++++--- userdiff.c | 10 +++++----- userdiff.h | 12 ++++++------ 4 files changed, 21 insertions(+), 16 deletions(-)
diff --git a/gpg-interface.c b/gpg-interface.c index 71a9382a61..5c824aeb25 100644 --- a/gpg-interface.c +++ b/gpg-interface.c @@ -34,7 +34,7 @@ static enum signature_trust_level configured_min_trust_level = TRUST_UNDEFINED; struct gpg_format { const char *name; - char *program; + const char *program; const char **verify_args; const char **sigs; int (*verify_signed_buffer)(struct signature_check *sigc, @@ -783,7 +783,7 @@ static int git_gpg_config(const char *var, const char *value, if (fmtname) { fmt = get_format_by_name(fmtname); - return git_config_string(&fmt->program, var, value); + return git_config_string((char **) &fmt->program, var, value); } return 0; diff --git a/merge-ll.c b/merge-ll.c index e29b15fa4a..180c19df67 100644 --- a/merge-ll.c +++ b/merge-ll.c @@ -27,7 +27,7 @@ typedef enum ll_merge_result (*ll_merge_fn)(const struct ll_merge_driver *, struct ll_merge_driver { const char *name; - char *description; + const char *description; ll_merge_fn fn; char *recursive; struct ll_merge_driver *next; @@ -304,8 +304,13 @@ static int read_merge_config(const char *var, const char *value, ll_user_merge_tail = &(fn->next); } - if (!strcmp("name", key)) - return git_config_string(&fn->description, var, value); + if (!strcmp("name", key)) { + /* + * The description is leaking, but that's okay as we want to + * keep around the merge drivers anyway. + */ + return git_config_string((char **) &fn->description, var, value); + } if (!strcmp("driver", key)) { if (!value) diff --git a/userdiff.c b/userdiff.c index 82bc76b910..371032a413 100644 --- a/userdiff.c +++ b/userdiff.c @@ -399,7 +399,7 @@ static struct userdiff_driver *userdiff_find_by_namelen(const char *name, size_t static int parse_funcname(struct userdiff_funcname *f, const char *k, const char *v, int cflags) { - if (git_config_string(&f->pattern, k, v) < 0) + if (git_config_string((char **) &f->pattern, k, v) < 0) return -1; f->cflags = cflags; return 0; @@ -445,15 +445,15 @@ int userdiff_config(const char *k, const char *v) if (!strcmp(type, "binary")) return parse_tristate(&drv->binary, k, v); if (!strcmp(type, "command")) - return git_config_string(&drv->external, k, v); + return git_config_string((char **) &drv->external, k, v); if (!strcmp(type, "textconv")) - return git_config_string(&drv->textconv, k, v); + return git_config_string((char **) &drv->textconv, k, v); if (!strcmp(type, "cachetextconv")) return parse_bool(&drv->textconv_want_cache, k, v); if (!strcmp(type, "wordregex")) - return git_config_string(&drv->word_regex, k, v); + return git_config_string((char **) &drv->word_regex, k, v); if (!strcmp(type, "algorithm")) - return git_config_string(&drv->algorithm, k, v); + return git_config_string((char **) &drv->algorithm, k, v); return 0; } diff --git a/userdiff.h b/userdiff.h index cc8e5abfef..d726804c3e 100644 --- a/userdiff.h +++ b/userdiff.h @@ -7,19 +7,19 @@ struct index_state; struct repository; struct userdiff_funcname { - char *pattern; + const char *pattern; int cflags; }; struct userdiff_driver { const char *name; - char *external; - char *algorithm; + const char *external; + const char *algorithm; int binary; struct userdiff_funcname funcname; - char *word_regex; - char *word_regex_multi_byte; - char *textconv; + const char *word_regex; + const char *word_regex_multi_byte; + const char *textconv; struct notes_cache *textconv_cache; int textconv_want_cache; };
-- 2.45.1.313.g3a57aa566a.dirty