Re: [PATCH bpf-next v2 8/8] bpf: Exercise syscall operations for inode and sk storage

[Song Liu]

> On Nov 3, 2020, at 7:31 AM, KP Singh <kpsingh@xxxxxxxxxxxx> wrote:
> 
> From: KP Singh <kpsingh@xxxxxxxxxx>

A short commit log would be great...

> 
> Signed-off-by: KP Singh <kpsingh@xxxxxxxxxx>
> ---
> .../bpf/prog_tests/test_local_storage.c          | 16 +++++++++++++++-
> 1 file changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/testing/selftests/bpf/prog_tests/test_local_storage.c b/tools/testing/selftests/bpf/prog_tests/test_local_storage.c
> index feba23f8848b..2e64baabb50d 100644
> --- a/tools/testing/selftests/bpf/prog_tests/test_local_storage.c
> +++ b/tools/testing/selftests/bpf/prog_tests/test_local_storage.c
> @@ -145,7 +145,7 @@ bool check_syscall_operations(int map_fd, int obj_fd)
> void test_test_local_storage(void)
> {
> 	char tmp_exec_path[PATH_MAX] = "/tmp/copy_of_rmXXXXXX";
> -	int err, serv_sk = -1, task_fd = -1;
> +	int err, serv_sk = -1, task_fd = -1, rm_fd = -1;
> 	struct local_storage *skel = NULL;
> 
> 	skel = local_storage__open_and_load();
> @@ -169,6 +169,15 @@ void test_test_local_storage(void)
> 	if (CHECK(err < 0, "copy_rm", "err %d errno %d\n", err, errno))
> 		goto close_prog;
> 
> +	rm_fd = open(tmp_exec_path, O_RDONLY);
> +	if (CHECK(rm_fd < 0, "open", "failed to open %s err:%d, errno:%d",
> +		  tmp_exec_path, rm_fd, errno))
> +		goto close_prog;
> +
> +	if (!check_syscall_operations(bpf_map__fd(skel->maps.inode_storage_map),
> +				      rm_fd))
> +		goto close_prog;
> +
> 	/* Sets skel->bss->monitored_pid to the pid of the forked child
> 	 * forks a child process that executes tmp_exec_path and tries to
> 	 * unlink its executable. This operation should be denied by the loaded
> @@ -197,9 +206,14 @@ void test_test_local_storage(void)
> 	CHECK(skel->data->sk_storage_result != 0, "sk_storage_result",
> 	      "sk_local_storage not set\n");
> 
> +	if (!check_syscall_operations(bpf_map__fd(skel->maps.sk_storage_map),
> +				      serv_sk))
> +		goto close_prog;

We shouldn't need this goto, otherwise we may leak serv_sk. 

> +
> 	close(serv_sk);
> 
> close_prog:
> +	close(rm_fd);
> 	close(task_fd);
> 	local_storage__destroy(skel);
> }
> -- 
> 2.29.1.341.ge80a0c044ae-goog
>