2020년 6월 15일 (월) 오전 9:18, Namjae Jeon <namjae.jeon@xxxxxxxxxxx>님이 작성:
>
> > Allow to change permission masks, allow_utime, errors. But ignore other options.
> >
> > Signed-off-by: Hyunchul Lee <hyc.lee@xxxxxxxxx>
> > ---
> > fs/exfat/super.c | 40 +++++++++++++++++++++++++++++-----------
> > 1 file changed, 29 insertions(+), 11 deletions(-)
> >
> > diff --git a/fs/exfat/super.c b/fs/exfat/super.c index 61c6cf240c19..3c1d47289ba2 100644
> > --- a/fs/exfat/super.c
> > +++ b/fs/exfat/super.c
> > @@ -696,9 +696,13 @@ static void exfat_free(struct fs_context *fc) static int
> > exfat_reconfigure(struct fs_context *fc) {
> > struct super_block *sb = fc->root->d_sb;
> > + struct exfat_sb_info *sbi = EXFAT_SB(sb);
> > + struct exfat_mount_options *new_opts;
> > int ret;
> > bool new_rdonly;
> >
> > + new_opts = &((struct exfat_sb_info *)fc->s_fs_info)->options;
> > +
> > new_rdonly = fc->sb_flags & SB_RDONLY;
> > if (new_rdonly != sb_rdonly(sb)) {
> > if (new_rdonly) {
> > @@ -708,6 +712,12 @@ static int exfat_reconfigure(struct fs_context *fc)
> > return ret;
> > }
> > }
> > +
> > + /* allow to change these options but ignore others */
> > + sbi->options.fs_fmask = new_opts->fs_fmask;
> > + sbi->options.fs_dmask = new_opts->fs_dmask;
> > + sbi->options.allow_utime = new_opts->allow_utime;
> > + sbi->options.errors = new_opts->errors;
> Is there any reason why you allow a few options on remount ?
while exfat is remounted, inodes are not reclaimed. So I think
changing fs_uid, fs_gid, or time_offset is not impossible.
And I am not sure changing the iocharset is safe.
I am curious about your opinion.
Thanks.
> > return 0;
> > }
> >
> > @@ -726,17 +736,25 @@ static int exfat_init_fs_context(struct fs_context *fc)
> > if (!sbi)
> > return -ENOMEM;
> >
> > - mutex_init(&sbi->s_lock);
> > - ratelimit_state_init(&sbi->ratelimit, DEFAULT_RATELIMIT_INTERVAL,
> > - DEFAULT_RATELIMIT_BURST);
> > -
> > - sbi->options.fs_uid = current_uid();
> > - sbi->options.fs_gid = current_gid();
> > - sbi->options.fs_fmask = current->fs->umask;
> > - sbi->options.fs_dmask = current->fs->umask;
> > - sbi->options.allow_utime = -1;
> > - sbi->options.iocharset = exfat_default_iocharset;
> > - sbi->options.errors = EXFAT_ERRORS_RO;
> > + if (fc->root) {
> > + /* reconfiguration */
> > + memcpy(&sbi->options, &EXFAT_SB(fc->root->d_sb)->options,
> > + sizeof(struct exfat_mount_options));
> > + sbi->options.iocharset = exfat_default_iocharset;
> > + } else {
> > + mutex_init(&sbi->s_lock);
> > + ratelimit_state_init(&sbi->ratelimit,
> > + DEFAULT_RATELIMIT_INTERVAL,
> > + DEFAULT_RATELIMIT_BURST);
> > +
> > + sbi->options.fs_uid = current_uid();
> > + sbi->options.fs_gid = current_gid();
> > + sbi->options.fs_fmask = current->fs->umask;
> > + sbi->options.fs_dmask = current->fs->umask;
> > + sbi->options.allow_utime = -1;
> > + sbi->options.iocharset = exfat_default_iocharset;
> > + sbi->options.errors = EXFAT_ERRORS_RO;
> > + }
> >
> > fc->s_fs_info = sbi;
> > fc->ops = &exfat_context_ops;
> > --
> > 2.17.1
>
>
