Re: [PATCH 1/3] ovl: force read-only sb on failure to create index dir

Vivek Goyal
2020-07-14T18:18:11Z

On Mon, Jul 13, 2020 at 05:19:43PM +0300, Amir Goldstein wrote:
> With index feature enabled, on failure to create index dir, overlay
> is being mounted read-only. However, we do not forbid user to remount
> overlay read-write. Fix that by setting ofs->workdir to NULL, which
> prevents remount read-write.
>
> Signed-off-by: Amir Goldstein <amir73il@gmail.com>

This patch does not apply for me. What branch you have generated it
against. I am using 5.8-rc4.

Vivek

> ---
> fs/overlayfs/super.c | 11 ++++++-----
> 1 file changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
> index 4b7cb2d98203..41d7fe2b8129 100644
> --- a/fs/overlayfs/super.c
> +++ b/fs/overlayfs/super.c
> @@ -1374,12 +1374,13 @@ static int ovl_get_indexdir(struct super_block *sb, struct ovl_fs *ofs,
> goto out;
> }
>
> + /* index dir will act also as workdir */
> + iput(ofs->workdir_trap);
> + ofs->workdir_trap = NULL;
> + dput(ofs->workdir);
> + ofs->workdir = NULL;
> ofs->indexdir = ovl_workdir_create(ofs, OVL_INDEXDIR_NAME, true);
> if (ofs->indexdir) {
> - /* index dir will act also as workdir */
> - iput(ofs->workdir_trap);
> - ofs->workdir_trap = NULL;
> - dput(ofs->workdir);
> ofs->workdir = dget(ofs->indexdir);
>
> err = ovl_setup_trap(sb, ofs->indexdir, &ofs->indexdir_trap,
> @@ -1884,7 +1885,7 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent)
> if (!ovl_upper_mnt(ofs))
> sb->s_flags |= SB_RDONLY;
>
> - if (!(ovl_force_readonly(ofs)) && ofs->config.index) {
> + if (!ovl_force_readonly(ofs) && ofs->config.index) {
> err = ovl_get_indexdir(sb, ofs, oe, &upperpath);
> if (err)
> goto out_free_oe;
> --
> 2.17.1
>