diff mbox series

[2/2] exfat: allow to change some mount options for remount

Message ID 20200612094250.9347-2-hyc.lee@gmail.com (mailing list archive)
State New, archived
Headers show
Series [1/2] exfat: call sync_filesystem for read-only remount | expand

Commit Message

Hyunchul Lee June 12, 2020, 9:42 a.m. UTC 
Allow to change permission masks, allow_utime,
errors. But ignore other options.

Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
---
 fs/exfat/super.c | 40 +++++++++++++++++++++++++++++-----------
 1 file changed, 29 insertions(+), 11 deletions(-)

Comments

Namjae Jeon June 15, 2020, 12:18 a.m. UTC | #1 
> Allow to change permission masks, allow_utime, errors. But ignore other options.
> 
> Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
> ---
>  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 ?
>  	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
Hyunchul Lee June 15, 2020, 2:12 a.m. UTC | #2 
2020년 6월 15일 (월) 오전 9:18, Namjae Jeon <namjae.jeon@samsung.com>님이 작성:
>
> > Allow to change permission masks, allow_utime, errors. But ignore other options.
> >
> > Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
> > ---
> >  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
>
>
diff mbox series

Patch

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;
 	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;