From: Darrick J. Wong <darrick.wong@xxxxxxxxxx> The ext4 fstrim implementation uses the block bitmaps to find free space that can be discarded. If we haven't replayed the journal, the bitmaps will be stale and we absolutely *cannot* use stale metadata to zap the underlying storage. Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> --- fs/ext4/ioctl.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index 3c4f8bb59f8a..bab3da4f1e0d 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -1000,6 +1000,13 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) if (!blk_queue_discard(q)) return -EOPNOTSUPP; + /* + * We haven't replayed the journal, so we cannot use our + * block-bitmap-guided storage zapping commands. + */ + if (test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) + return -EROFS; + if (copy_from_user(&range, (struct fstrim_range __user *)arg, sizeof(range))) return -EFAULT;
