Re: [PATCH v2] fs: Fix page_mkwrite off-by-one errors

From: Richard Weinberger
Date: Fri Nov 29 2019 - 11:36:02 EST


----- UrsprÃngliche Mail -----
> Von: "Andreas Gruenbacher" <agruenba@xxxxxxxxxx>
> An: "Christoph Hellwig" <hch@xxxxxxxxxxxxx>, "Darrick" <darrick.wong@xxxxxxxxxx>
> CC: "Andreas Gruenbacher" <agruenba@xxxxxxxxxx>, "torvalds" <torvalds@xxxxxxxxxxxxxxxxxxxx>, "linux-kernel"
> <linux-kernel@xxxxxxxxxxxxxxx>, "Al Viro" <viro@xxxxxxxxxxxxxxxxxx>, "Jeff Layton" <jlayton@xxxxxxxxxx>, "Sage Weil"
> <sage@xxxxxxxxxx>, "Ilya Dryomov" <idryomov@xxxxxxxxx>, "tytso" <tytso@xxxxxxx>, "Andreas Dilger"
> <adilger.kernel@xxxxxxxxx>, "Jaegeuk Kim" <jaegeuk@xxxxxxxxxx>, "Chao Yu" <chao@xxxxxxxxxx>, linux-xfs@xxxxxxxxxxxxxxx,
> "linux-fsdevel" <linux-fsdevel@xxxxxxxxxxxxxxx>, "richard" <richard@xxxxxx>, "Artem Bityutskiy" <dedekind1@xxxxxxxxx>,
> "Adrian Hunter" <adrian.hunter@xxxxxxxxx>, ceph-devel@xxxxxxxxxxxxxxx, linux-ext4@xxxxxxxxxxxxxxx,
> linux-f2fs-devel@xxxxxxxxxxxxxxxxxxxxx, "linux-mtd" <linux-mtd@xxxxxxxxxxxxxxxxxxx>, "Chris Mason" <clm@xxxxxx>, "Josef
> Bacik" <josef@xxxxxxxxxxxxxx>, "David Sterba" <dsterba@xxxxxxxx>, "linux-btrfs" <linux-btrfs@xxxxxxxxxxxxxxx>
> Gesendet: Freitag, 29. November 2019 15:20:45
> Betreff: [PATCH v2] fs: Fix page_mkwrite off-by-one errors

> The check in block_page_mkwrite meant to determine whether an offset is
> within the inode size is off by one. This bug has spread to
> iomap_page_mkwrite and to several filesystems (ubifs, ext4, f2fs, ceph).
> To fix that, introduce a new page_mkwrite_check_truncate helper that
> checks for truncate and computes the bytes in the page up to EOF, and
> use that helper in the above mentioned filesystems and in btrfs.
>
> Signed-off-by: Andreas Gruenbacher <agruenba@xxxxxxxxxx>

Thank you for fixing UBIFS!

Acked-by: Richard Weinberger <richard@xxxxxx>

Thanks,
//richard