[PATCH 4.4 148/230] Its wrong to add len to sector_nr in raid10 reshape twice

From: Greg Kroah-Hartman
Date: Fri Mar 22 2019 - 07:34:42 EST

4.4-stable review patch. If anyone has any objections, please let me know.


From: Xiao Ni <xni@xxxxxxxxxx>

commit b761dcf1217760a42f7897c31dcb649f59b2333e upstream.

In reshape_request it already adds len to sector_nr already. It's wrong to add len to
sector_nr again after adding pages to bio. If there is bad block it can't copy one chunk
at a time, it needs to goto read_more. Now the sector_nr is wrong. It can cause data

Cc: stable@xxxxxxxxxxxxxxx # v3.16+
Signed-off-by: Xiao Ni <xni@xxxxxxxxxx>
Signed-off-by: Song Liu <songliubraving@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

drivers/md/raid10.c | 1 -
1 file changed, 1 deletion(-)

--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -4442,7 +4442,6 @@ bio_full:
read_bio->bi_next = NULL;
- sector_nr += nr_sectors;
sectors_done += nr_sectors;
if (sector_nr <= last)
goto read_more;