Re: [PATCH bpf-next v4 8/9] bpf: Add tests for task_local_storage

[KP Singh]

On Thu, Nov 5, 2020 at 11:03 PM Martin KaFai Lau <kafai@xxxxxx> wrote:
>
> On Thu, Nov 05, 2020 at 03:47:54PM +0100, KP Singh wrote:
> > From: KP Singh <kpsingh@xxxxxxxxxx>
> >
> > The test exercises the syscall based map operations by creating a pidfd
> > for the current process.
> >

[...]

> > +}
> > +
> > +unsigned int duration;
> static

Fixed.

>
> > +
> > +#define TEST_STORAGE_VALUE 0xbeefdead
> > +
> > +struct storage {
> > +     void *inode;
> > +     unsigned int value;
> > +     /* Lock ensures that spin locked versions of local stoage operations
> > +      * also work, most operations in this tests are still single threaded
> > +      */
> > +     struct bpf_spin_lock lock;
> > +};
> > +
> > +/* Copies an rm binary to a temp file. dest is a mkstemp template */
> > +int copy_rm(char *dest)
> static

FIxed.

[...]

> > +     ret = chmod(dest, 0100);
> > +     if (ret == -1)
> > +             return errno;
> > +
> > +     close(fd_in);
> > +     close(fd_out);
> fd_in and fd_out are not closed in error cases.

Fixed.

>
> >  {
> > -     char fname[PATH_MAX] = "/tmp/fileXXXXXX";
> > -     int fd;
> > +     int ret, fd_in, fd_out;
> > +     struct stat stat;
> >

[...]

> > + */
> > +int run_self_unlink(int *monitored_pid, const char *rm_path)
> static

Fixed.

>
> [ ... ]
>
> > +bool check_syscall_operations(int map_fd, int obj_fd)
> static

Fixed.

>
> [ ... ]
>
> >  void test_test_local_storage(void)
> >  {
> > +     char tmp_exec_path[PATH_MAX] = "/tmp/copy_of_rmXXXXXX";
> > +     int err, serv_sk = -1, task_fd = -1;
> >       struct local_storage *skel = NULL;
> > -     int err, duration = 0, serv_sk = -1;
> >

[...]

> > +     err = unlink(tmp_exec_path);

> Will tmp_exec_path file be removed if there is error earlier?

No. Since I cannot move this unlink as inode_unlink LSM hook sets the
inode_storage
result, I added another label close_prog_unlink which cleans it up for
the errors
before this succeeds.


>
> > +     if (CHECK(err != 0, "unlink", "unable to unlink %s: %d", tmp_exec_path,
> > +               errno))
> >               goto close_prog;
> >
> >       CHECK(skel->data->inode_storage_result != 0, "inode_storage_result",
> > @@ -56,5 +200,6 @@ void test_test_local_storage(void)
> >       close(serv_sk);
> >
> >  close_prog:
> > +     close(task_fd);
> >       local_storage__destroy(skel);
> >  }