mirrors/git
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

help: fix leaking return value from help_unknown_cmd()

Browse Source 
While `help_unknown_cmd()` would usually die on an unknown command, it
instead returns an autocorrected command when "help.autocorrect" is set.
But while the function is declared to return a string constant, it
actually returns an allocated string in that case. Callers thus aren't
aware that they have to free the string, leading to a memory leak.

Fix the function return type to be non-constant and free the returned
value at its only callsite.

Note that we cannot simply take ownership of `main_cmds.names[0]->name`
and then eventually free it. This is because the `struct cmdname` is
using a flex array to allocate the name, so the name pointer points into
the middle of the structure and thus cannot be freed.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Patrick Steinhardt
2024-11-20 14:39:45 +01:00
committed by Junio C Hamano
parent 889c597961
commit 7720dbe99b
3 changed files with 7 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
git.c
View File

@ -961,7 +961,9 @@ int cmd_main(int argc, const char **argv)
exit(1);
}
if (!done_help) {
strvec_replace(&args, 0, help_unknown_cmd(cmd));
char *assumed = help_unknown_cmd(cmd);
strvec_replace(&args, 0, assumed);
free(assumed);
cmd = args.v[0];
done_help = 1;
} else {

7
help.c
View File

@ -612,7 +612,7 @@ static const char bad_interpreter_advice[] =
N_("'%s' appears to be a git command, but we were not\n"
"able to execute it. Maybe git-%s is broken?");
const char *help_unknown_cmd(const char *cmd)
char *help_unknown_cmd(const char *cmd)
{
struct help_unknown_cmd_config cfg = { 0 };
int i, n, best_similarity = 0;
@ -695,9 +695,8 @@ const char *help_unknown_cmd(const char *cmd)
; /* still counting */
}
if (cfg.autocorrect && n == 1 && SIMILAR_ENOUGH(best_similarity)) {
const char *assumed = main_cmds.names[0]->name;
main_cmds.names[0] = NULL;
cmdnames_release(&main_cmds);
char *assumed = xstrdup(main_cmds.names[0]->name);
fprintf_ln(stderr,
_("WARNING: You called a Git command named '%s', "
"which does not exist."),

2
help.h
View File

@ -32,7 +32,7 @@ void list_all_other_cmds(struct string_list *list);
void list_cmds_by_category(struct string_list *list,
const char *category);
void list_cmds_by_config(struct string_list *list);
const char *help_unknown_cmd(const char *cmd);
char *help_unknown_cmd(const char *cmd);
void load_command_list(const char *prefix,
struct cmdnames *main_cmds,
struct cmdnames *other_cmds);