Re: [PATCH] fanotify06: add a test case for overlayfs

[Amir Goldstein <amir73il@gmail.com>]

CC: <linux-unionfs@vger.kernel.org>

On Wed, Apr 24, 2019 at 11:53 AM Amir Goldstein <amir73il@gmail.com> wrote:
>
> This test fails on overlayfs since kernel v4.19.
> Added a test case for overlayfs mount.
>
> Signed-off-by: Amir Goldstein <amir73il@gmail.com>
> ---
>
> Hi Cyril,
>
> The new test case covers a bug reported by Murphy Zhou:
> https://lore.kernel.org/linux-fsdevel/20190423065024.12695-1-jencce.kernel@gmail.com/
>
> Once again, I tried looking at making overlayfs test variant generic.
> Once again, I gave it up.
>
> Thanks,
> Amir.
>
>  .../kernel/syscalls/fanotify/fanotify06.c     | 74 +++++++++++++++----
>  1 file changed, 61 insertions(+), 13 deletions(-)
>
> diff --git a/testcases/kernel/syscalls/fanotify/fanotify06.c b/testcases/kernel/syscalls/fanotify/fanotify06.c
> index 6a2e2494f..62defb23c 100644
> --- a/testcases/kernel/syscalls/fanotify/fanotify06.c
> +++ b/testcases/kernel/syscalls/fanotify/fanotify06.c
> @@ -54,8 +54,23 @@ static int fd_notify[FANOTIFY_PRIORITIES][GROUPS_PER_PRIO];
>
>  static char event_buf[EVENT_BUF_LEN];
>
> -#define MOUNT_NAME "mntpoint"
> +#define MNTPOINT "mntpoint"
> +#define OVL_LOWER "ovl-lower"
> +#define OVL_UPPER "ovl-upper"
> +#define OVL_WORK "ovl-work"
> +#define OVL_MNT "ovl-mnt"
> +
>  static int mount_created;
> +static int ovl_mounted;
> +
> +static struct tcase {
> +       const char *tname;
> +       const char *mnt;
> +       int use_overlay;
> +} tcases[] = {
> +       { "Fanotify merge mount mark", MNTPOINT, 0 },
> +       { "Fanotify merge overlayfs mount mark", OVL_MNT, 1 },
> +};
>
>  static void create_fanotify_groups(void)
>  {
> @@ -72,12 +87,12 @@ static void create_fanotify_groups(void)
>                         ret = fanotify_mark(fd_notify[p][i],
>                                             FAN_MARK_ADD | FAN_MARK_MOUNT,
>                                             FAN_MODIFY,
> -                                           AT_FDCWD, ".");
> +                                           AT_FDCWD, fname);
>                         if (ret < 0) {
>                                 tst_brk(TBROK | TERRNO,
>                                         "fanotify_mark(%d, FAN_MARK_ADD | "
>                                         "FAN_MARK_MOUNT, FAN_MODIFY, AT_FDCWD,"
> -                                       " '.') failed", fd_notify[p][i]);
> +                                       " %s) failed", fd_notify[p][i], fname);
>                         }
>                         /* Add ignore mark for groups with higher priority */
>                         if (p == 0)
> @@ -130,11 +145,23 @@ static void verify_event(int group, struct fanotify_event_metadata *event)
>         }
>  }
>
> -void test01(void)
> +void test_fanotify(unsigned int n)
>  {
>         int ret;
>         unsigned int p, i;
>         struct fanotify_event_metadata *event;
> +       struct tcase *tc = &tcases[n];
> +
> +       tst_res(TINFO, "Test #%d: %s", n, tc->tname);
> +
> +       if (tc->use_overlay && !ovl_mounted) {
> +               tst_res(TCONF,
> +                       "overlayfs is not configured in this kernel.");
> +               return;
> +       }
> +
> +       sprintf(fname, "%s/tfile_%d", tc->mnt, getpid());
> +       SAFE_TOUCH(fname, 0644, NULL);
>
>         create_fanotify_groups();
>
> @@ -194,29 +221,50 @@ void test01(void)
>         cleanup_fanotify_groups();
>  }
>
> +static void setup_overlay(void)
> +{
> +       int ret;
> +
> +       SAFE_MKDIR(OVL_LOWER, 0755);
> +       SAFE_MKDIR(OVL_UPPER, 0755);
> +       SAFE_MKDIR(OVL_WORK, 0755);
> +       SAFE_MKDIR(OVL_MNT, 0755);
> +       ret = mount("overlay", OVL_MNT, "overlay", 0, "lowerdir="OVL_LOWER
> +                   ",upperdir="OVL_UPPER",workdir="OVL_WORK);
> +       if (ret < 0) {
> +               if (errno == ENODEV) {
> +                       tst_res(TINFO,
> +                               "overlayfs is not configured in this kernel.");
> +                       return;
> +               }
> +               tst_brk(TBROK | TERRNO, "overlayfs mount failed");
> +       }
> +       ovl_mounted = 1;
> +}
> +
>  static void setup(void)
>  {
> -       SAFE_MKDIR(MOUNT_NAME, 0755);
> -       SAFE_MOUNT(MOUNT_NAME, MOUNT_NAME, "none", MS_BIND, NULL);
> +       SAFE_MKDIR(MNTPOINT, 0755);
> +       SAFE_MOUNT(MNTPOINT, MNTPOINT, "none", MS_BIND, NULL);
>         mount_created = 1;
> -       SAFE_CHDIR(MOUNT_NAME);
>
> -       sprintf(fname, "tfile_%d", getpid());
> -       SAFE_FILE_PRINTF(fname, "1");
> +       setup_overlay();
>  }
>
>  static void cleanup(void)
>  {
>         cleanup_fanotify_groups();
>
> -       SAFE_CHDIR("../");
> +       if (ovl_mounted)
> +               SAFE_UMOUNT(OVL_MNT);
>
> -       if (mount_created && tst_umount(MOUNT_NAME) < 0)
> -               tst_brk(TBROK | TERRNO, "umount failed");
> +       if (mount_created)
> +               SAFE_UMOUNT(MNTPOINT);
>  }
>
>  static struct tst_test test = {
> -       .test_all = test01,
> +       .test = test_fanotify,
> +       .tcnt = ARRAY_SIZE(tcases),
>         .setup = setup,
>         .cleanup = cleanup,
>         .needs_tmpdir = 1,
> --
> 2.17.1
>