undef/git-commit-vandalism
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

reftable: ensure that obj_id_len is >= 2 on writing

Browse Source 
When writing the same hash many times, we might decide to use a
length-1 object ID prefix for the ObjectID => ref table, which is out
of spec.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Han-Wen Nienhuys 2022-02-21 18:46:08 +00:00 committed by Junio C Hamano
parent 45c2fcc2a0
commit b4007fcc6f
2 changed files with 40 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

37
reftable/readwrite_test.c
View File

@ -667,6 +667,42 @@ static void test_write_empty_table(void)
strbuf_release(&buf);
}
static void test_write_object_id_min_length(void)
{
struct reftable_write_options opts = {
.block_size = 75,
};
struct strbuf buf = STRBUF_INIT;
struct reftable_writer *w =
reftable_new_writer(&strbuf_add_void, &buf, &opts);
uint8_t hash[GIT_SHA1_RAWSZ] = {42};
struct reftable_ref_record ref = {
.update_index = 1,
.value_type = REFTABLE_REF_VAL1,
.value.val1 = hash,
};
int err;
int i;
reftable_writer_set_limits(w, 1, 1);
/* Write the same hash in many refs. If there is only 1 hash, the
* disambiguating prefix is length 0 */
for (i = 0; i < 256; i++) {
char name[256];
snprintf(name, sizeof(name), "ref%05d", i);
ref.refname = name;
err = reftable_writer_add_ref(w, &ref);
EXPECT_ERR(err);
}
err = reftable_writer_close(w);
EXPECT_ERR(err);
EXPECT(writer_stats(w)->object_id_len == 2);
reftable_writer_free(w);
strbuf_release(&buf);
}
static void test_write_empty_key(void)
{
struct reftable_write_options opts = { 0 };
@ -772,5 +808,6 @@ int readwrite_test_main(int argc, const char *argv[])
RUN_TEST(test_write_empty_key);
RUN_TEST(test_write_empty_table);
RUN_TEST(test_log_overflow);
RUN_TEST(test_write_object_id_min_length);
return 0;
}

4
reftable/writer.c
View File

@ -515,7 +515,9 @@ static void object_record_free(void *void_arg, void *key)
static int writer_dump_object_index(struct reftable_writer *w)
{
struct write_record_arg closure = { .w = w };
struct common_prefix_arg common = { NULL };
struct common_prefix_arg common = {
.max = 1, /* obj_id_len should be >= 2. */
};
if (w->obj_index_tree) {
infix_walk(w->obj_index_tree, &update_common, &common);
}