From: NeilBrown Date: Sun, 5 Jan 2014 23:35:34 +0000 (+1100) Subject: md/raid10: fix bug when raid10 recovery fails to recover a block. X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=e8b849158508565e0cd6bc80061124afc5879160;p=openwrt%2Fstaging%2Fblogic.git md/raid10: fix bug when raid10 recovery fails to recover a block. commit e875ecea266a543e643b19e44cf472f1412708f9 md/raid10 record bad blocks as needed during recovery. added code to the "cannot recover this block" path to record a bad block rather than fail the whole recovery. Unfortunately this new case was placed *after* r10bio was freed rather than *before*, yet it still uses r10bio. This is will crash with a null dereference. So move the freeing of r10bio down where it is safe. Cc: stable@vger.kernel.org (v3.1+) Fixes: e875ecea266a543e643b19e44cf472f1412708f9 Reported-by: Damian Nowak URL: https://bugzilla.kernel.org/show_bug.cgi?id=68181 Signed-off-by: NeilBrown --- diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 65285211568f..06eeb99ea6fc 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -3218,10 +3218,6 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr, if (j == conf->copies) { /* Cannot recover, so abort the recovery or * record a bad block */ - put_buf(r10_bio); - if (rb2) - atomic_dec(&rb2->remaining); - r10_bio = rb2; if (any_working) { /* problem is that there are bad blocks * on other device(s) @@ -3253,6 +3249,10 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr, mirror->recovery_disabled = mddev->recovery_disabled; } + put_buf(r10_bio); + if (rb2) + atomic_dec(&rb2->remaining); + r10_bio = rb2; break; } }