Linux 4.4.177

[thirdparty/kernel/stable-queue.git] / releases / 4.4.177 / it-s-wrong-to-add-len-to-sector_nr-in-raid10-reshape-twice.patch

From b761dcf1217760a42f7897c31dcb649f59b2333e Mon Sep 17 00:00:00 2001
From: Xiao Ni <xni@redhat.com>
Date: Fri, 8 Mar 2019 23:52:05 +0800
Subject: It's wrong to add len to sector_nr in raid10 reshape twice

From: Xiao Ni <xni@redhat.com>

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
corruption.

Cc: stable@vger.kernel.org # v3.16+
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 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:
 	atomic_inc(&r10_bio->remaining);
 	read_bio->bi_next = NULL;
 	generic_make_request(read_bio);
-	sector_nr += nr_sectors;
 	sectors_done += nr_sectors;
 	if (sector_nr <= last)
 		goto read_more;