Re: [PATCH 04/33] notes: make get_note return pointer to struct object_id
- From
René Scharfe <l.s.r@web.de>
- Date
- Jul 15, 2017, 18:15 UTC
- Message-ID
- <4c10c481-45c9-1b36-d83f-f70adca60bdb@web.de>
- In-Reply-To
- <20170530173109.54904-5-bmwill@google.com>
Am 30.05.2017 um 19:30 schrieb Brandon Williams:
Show 9 quoted lines
> @@ -392,7 +392,7 @@ static int add(int argc, const char **argv, const char *prefix)
> const char *object_ref;
> struct notes_tree *t;
> unsigned char object[20], new_note[20];
> - const unsigned char *note;
> + const struct object_id *note;
> struct note_data d = { 0, 0, NULL, STRBUF_INIT };
> struct option options[] = {
> { OPTION_CALLBACK, 'm', "message", &d, N_("message"),In between here, note can be set to NULL...
Show 6 quoted lines
> @@ -453,7 +453,7 @@ static int add(int argc, const char **argv, const char *prefix) > sha1_to_hex(object)); > } > > - prepare_note_data(object, &d, note); > + prepare_note_data(object, &d, note->hash);
... which we then dereference here.
Show 6 quoted lines
> @@ -598,13 +598,13 @@ static int append_edit(int argc, const char **argv, const char *prefix) > t = init_notes_check(argv[0], NOTES_INIT_WRITABLE); > note = get_note(t, object); > > - prepare_note_data(object, &d, edit ? note : NULL); > + prepare_note_data(object, &d, edit && note ? note->hash : NULL);
Here a NULL check was added; we need a similar one above as well.
-- >8 -- Subject: [PATCH] notes: don't access hash of NULL object_id pointer
Check if note is NULL, as we already do for different purposes a few lines above, and pass a NULL pointer to prepare_note_data() in that case instead of trying to access the hash member.
Found with Clang's UBSan.
Signed-off-by: Rene Scharfe <l.s.r@web.de> --- The third parameter of prepare_note_data() could easily be turned into an object_id pointer (and it should), but this patch is meant to be a minimal fix.
builtin/notes.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/builtin/notes.c b/builtin/notes.c index 77573cf1ea..4303848e04 100644 --- a/builtin/notes.c +++ b/builtin/notes.c @@ -456,7 +456,7 @@ static int add(int argc, const char **argv, const char *prefix) oid_to_hex(&object)); } - prepare_note_data(&object, &d, note->hash); + prepare_note_data(&object, &d, note ? note->hash : NULL); if (d.buf.len || allow_empty) { write_note_data(&d, new_note.hash); if (add_note(t, &object, &new_note, combine_notes_overwrite))
-- 2.13.3