selftests/bpf: Add tests for write-only stacks/queues

For write-only stacks and queues bpf_map_update_elem should be allowed, but
bpf_map_lookup_elem and bpf_map_lookup_and_delete_elem should fail with EPERM.

Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200527185700.14658-6-a.s.protopopov@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Anton Protopopov 2020-05-27 18:57:00 +00:00 committed by Alexei Starovoitov
parent 1ea0f9120c
commit 43dd115b1f

View File

@ -1405,7 +1405,7 @@ static void test_map_rdonly(void)
close(fd);
}
static void test_map_wronly(void)
static void test_map_wronly_hash(void)
{
int fd, key = 0, value = 0;
@ -1429,6 +1429,44 @@ static void test_map_wronly(void)
close(fd);
}
static void test_map_wronly_stack_or_queue(enum bpf_map_type map_type)
{
int fd, value = 0;
assert(map_type == BPF_MAP_TYPE_QUEUE ||
map_type == BPF_MAP_TYPE_STACK);
fd = bpf_create_map(map_type, 0, sizeof(value), MAP_SIZE,
map_flags | BPF_F_WRONLY);
/* Stack/Queue maps do not support BPF_F_NO_PREALLOC */
if (map_flags & BPF_F_NO_PREALLOC) {
assert(fd < 0 && errno == EINVAL);
return;
}
if (fd < 0) {
printf("Failed to create map '%s'!\n", strerror(errno));
exit(1);
}
value = 1234;
assert(bpf_map_update_elem(fd, NULL, &value, BPF_ANY) == 0);
/* Peek element should fail */
assert(bpf_map_lookup_elem(fd, NULL, &value) == -1 && errno == EPERM);
/* Pop element should fail */
assert(bpf_map_lookup_and_delete_elem(fd, NULL, &value) == -1 &&
errno == EPERM);
close(fd);
}
static void test_map_wronly(void)
{
test_map_wronly_hash();
test_map_wronly_stack_or_queue(BPF_MAP_TYPE_STACK);
test_map_wronly_stack_or_queue(BPF_MAP_TYPE_QUEUE);
}
static void prepare_reuseport_grp(int type, int map_fd, size_t map_elem_size,
__s64 *fds64, __u64 *sk_cookies,
unsigned int n)