[PATCH 3.19.y-ckt 037/146] md/raid5: don't record new size if resize_stripes fails.

From: Kamal Mostafa
Date: Wed Jun 17 2015 - 19:37:34 EST


3.19.8-ckt2 -stable review patch. If anyone has any objections, please let me know.

------------------

From: NeilBrown <neilb@xxxxxxx>

commit 6e9eac2dcee5e19f125967dd2be3e36558c42fff upstream.

If any memory allocation in resize_stripes fails we will return
-ENOMEM, but in some cases we update conf->pool_size anyway.

This means that if we try again, the allocations will be assumed
to be larger than they are, and badness results.

So only update pool_size if there is no error.

This bug was introduced in 2.6.17 and the patch is suitable for
-stable.

Fixes: ad01c9e3752f ("[PATCH] md: Allow stripes to be expanded in preparation for expanding an array")
Signed-off-by: NeilBrown <neilb@xxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
drivers/md/raid5.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 8577cc7..e421016 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -1936,7 +1936,8 @@ static int resize_stripes(struct r5conf *conf, int newsize)

conf->slab_cache = sc;
conf->active_name = 1-conf->active_name;
- conf->pool_size = newsize;
+ if (!err)
+ conf->pool_size = newsize;
return err;
}

--
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/