Re: [PATCH v8] ntfs: mount hibernated volumes read-only regardless of errors=

[Namjae Jeon]

On Tue, Sep 22, 2026 at 7:11 PM Hongling Zeng <zenghongling@xxxxxxxxxx> wrote:
>
> The hibernation check in load_system_files() only converts the
> superblock to read-only under errors=remount-ro.  With the default
> errors=continue (and with errors=panic), a hibernated volume is
> mounted read-write and the mount-time $LogFile emptying writes to it,
> although a hibernated volume must not be written to at all.
>
> Drop the on_errors term so that a hibernated volume, or a volume whose
> hibernation state cannot be determined, always mounts read-only.
> NVolErrors() is still recorded, so ntfs_reconfigure() keeps refusing
> remounts to read-write, and the $LogFile emptying is skipped by its
> !sb_rdonly() check.
>
> The check itself must not apply the errors= policy either: it runs
> before SB_RDONLY is set, and ntfs_lookup_inode_by_name() and ntfs_iget()
> call ntfs_error() internally on corruption or I/O errors, which under
> errors=panic would panic the machine before the read-only fallback has
> made its decision.  Temporarily substitute errors=remount-ro for
> errors=panic around the check: nested ntfs_error() calls then fall
> back to read-only, and any read-only transition they trigger is
> preserved even when the error is not propagated to the check's return
> value or recorded in NVolErrors().  This is safe during initial mount,
> before the super block is published.
>
> If the check reports hibernation or fails, set SB_RDONLY and record
> NVolErrors() unconditionally: hibernation safety takes precedence over
> the errors= policy.  A volume with errors recorded during the check or
> earlier in the mount, e.g. when loading the LogFile, also stays
> read-only, matching what ntfs_reconfigure() enforces for remounts.
>
> Fixes: 6251f0b0de7d ("ntfs: update super block operations")
> Cc: stable@xxxxxxxxxxxxxxx
> Suggested-by: Baolin Liu <liubaolin@xxxxxxxxxx>
> Reviewed-by: Baolin Liu <liubaolin@xxxxxxxxxx>
> Reviewed-by: Hyunchul Lee <hyc.lee@xxxxxxxxx>
> Signed-off-by: Hongling Zeng <zenghongling@xxxxxxxxxx>
Applied it to #ntfs-next.
Thanks!