On Tue, Aug 13, 2024 at 09:55:10AM -0700, Junio C Hamano wrote:
> Patrick Steinhardt <ps@xxxxxx> writes:
>
> > There are various memory leaks hit by git-format-patch(1). Basically all
> > of them are trivial, except that un-setting `diffopt.no_free` requires
> > us to unset the `diffopt.file` because we manually close it already.
> >
> > Signed-off-by: Patrick Steinhardt <ps@xxxxxx>
> > ---
> > builtin/log.c | 12 +++++++++---
> > t/t4014-format-patch.sh | 1 +
> > 2 files changed, 10 insertions(+), 3 deletions(-)
> >
> > diff --git a/builtin/log.c b/builtin/log.c
> > index a73a767606..ff997a0d0e 100644
> > --- a/builtin/log.c
> > +++ b/builtin/log.c
> > @@ -1833,6 +1833,7 @@ static struct commit *get_base_commit(const struct format_config *cfg,
> > }
> >
> > rev[i] = merge_base->item;
> > + free_commit_list(merge_base);
> > }
> >
> > if (rev_nr % 2)
>
> This is correct, but isn't merge_base leaking when there are
> multiple and we are not dying on failure? Perhaps something along
> this line?
Yes, good catch.
> struct commit_list *merge_base = NULL;
> if (repo_get_merge_bases(the_repository,
> rev[2 * i],
> rev[2 * i + 1], &merge_base) < 0 ||
> !merge_base || merge_base->next) {
> if (die_on_failure) {
> die(_("failed to find exact merge base"));
> } else {
> + free_commit_list(merge_base);
> free(rev);
> return NULL;
> }
> }
>
> > @@ -2548,12 +2550,13 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
> > else
> > print_signature(signature, rev.diffopt.file);
> > }
> > - if (output_directory)
> > + if (output_directory) {
> > fclose(rev.diffopt.file);
> > + rev.diffopt.file = NULL;
>
> Is this a leakfix, or just a general code hygiene improvement?
Not a leak fix, but required because of the leak fix. As we now unset
`rev.diffopt.no_free`, `release_revisions()` will call `diff_free()` and
try to close the file pointer. But as we already did, it would cause a
segfault as we now try to close it twice.
Patrick
