On Fri, Jul 28, 2017 at 01:16:37PM +0200, Jan Kara wrote: > ext4_find_unwritten_pgoff() does not properly handle a situation when > starting index is in the middle of a page and blocksize < pagesize. The > following command shows the bug on filesystem with 1k blocksize: > > xfs_io -f -c "falloc 0 4k" \ > -c "pwrite 1k 1k" \ > -c "pwrite 3k 1k" \ > -c "seek -a -r 0" foo > > In this example, neither lseek(fd, 1024, SEEK_HOLE) nor lseek(fd, 2048, > SEEK_DATA) will return the correct result. > > Fix the problem by neglecting buffers in a page before starting offset. > > Reported-by: Andreas Gruenbacher <agruenba@xxxxxxxxxx> > CC: stable@xxxxxxxxxxxxxxx > Signed-off-by: Jan Kara <jack@xxxxxxx> Thanks, applied. - Ted
