libbpf: Fix memory leak and possible double-free in hashmap__clear

[ Upstream commit 229bf8bf4d910510bc1a2fd0b89bd467cd71050d ]

Fix memory leak in hashmap_clear() not freeing hashmap_entry structs for each
of the remaining entries. Also NULL-out bucket list to prevent possible
double-free between hashmap__clear() and hashmap__free().

Running test_progs-asan flavor clearly showed this problem.

Reported-by: Alston Tang <alston64@fb.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200429012111.277390-5-andriin@fb.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Andrii Nakryiko 2020-04-28 18:21:04 -07:00 committed by Greg Kroah-Hartman
parent 072d23eef6
commit 269e7b43f2

View File

@ -56,7 +56,14 @@ struct hashmap *hashmap__new(hashmap_hash_fn hash_fn,
void hashmap__clear(struct hashmap *map)
{
struct hashmap_entry *cur, *tmp;
int bkt;
hashmap__for_each_entry_safe(map, cur, tmp, bkt) {
free(cur);
}
free(map->buckets);
map->buckets = NULL;
map->cap = map->cap_bits = map->sz = 0;
}