fsck: do not dereference NULL while checking resolve-undo data

gitster · gitster · commit e0ad13977a7f · 2022-07-11T16:26:33.000-07:00
When we found an invalid object recorded in the resolve-undo data,
we would have ended up dereferencing NULL while fsck.  Reporting the
problem and going on to the next object is the right thing to do
here.

Noticed by SZEDER Gábor.

Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
diff --git a/builtin/fsck.c b/builtin/fsck.c
@@ -784,6 +784,7 @@ static int fsck_resolve_undo(struct index_state *istate)
 				error(_("%s: invalid sha1 pointer in resolve-undo"),
 				      oid_to_hex(&ru->oid[i]));
 				errors_found |= ERROR_REFS;
+				continue;
 			}
 			obj->flags |= USED;
 			fsck_put_object_name(&fsck_walk_options, &ru->oid[i],

Original file line number	Diff line number	Diff line change
`@@ -784,6 +784,7 @@ static int fsck_resolve_undo(struct index_state *istate)`
`784`	`784`	`error(_("%s: invalid sha1 pointer in resolve-undo"),`
`785`	`785`	`oid_to_hex(&ru->oid[i]));`
`786`	`786`	`errors_found \|= ERROR_REFS;`
	`787`	`+ continue;`
`787`	`788`	`}`
`788`	`789`	`obj->flags \|= USED;`
`789`	`790`	`fsck_put_object_name(&fsck_walk_options, &ru->oid[i],`