On Fri, Nov 29, 2019 at 03:20:45PM +0100, Andreas Gruenbacher wrote: > 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> > > --- > > This patch has a trivial conflict with commit "iomap: Fix overflow in > iomap_page_mkwrite" in Darrick's iomap pull request for 5.5: > > https://lore.kernel.org/lkml/20191125190907.GN6219@magnolia/ > --- > fs/btrfs/inode.c | 15 ++++----------- For the btrfs part Acked-by: David Sterba <dsterba@xxxxxxxx> and reviewed that the change is equivalent.