From 54ed4ed8f9a5071a3bbae2e037376d8c02b9629b Mon Sep 17 00:00:00 2001 From: Lars Ellenberg Date: Wed, 25 Jun 2014 17:52:38 +0200 Subject: [PATCH] drbd: fix NULL pointer deref in blk_add_request_payload Discards don't have any payload. But the scsi layer still expects a bio_vec it can use internally, see sd_setup_discard_cmnd() and blk_add_request_payload(). Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg Signed-off-by: Jens Axboe --- drivers/block/drbd/drbd_receiver.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c index b6c8aaf4931b..5b17ec88ea05 100644 --- a/drivers/block/drbd/drbd_receiver.c +++ b/drivers/block/drbd/drbd_receiver.c @@ -1337,8 +1337,11 @@ int drbd_submit_peer_request(struct drbd_device *device, return 0; } + /* Discards don't have any payload. + * But the scsi layer still expects a bio_vec it can use internally, + * see sd_setup_discard_cmnd() and blk_add_request_payload(). */ if (peer_req->flags & EE_IS_TRIM) - nr_pages = 0; /* discards don't have any payload. */ + nr_pages = 1; /* In most cases, we will only need one bio. But in case the lower * level restrictions happen to be different at this offset on this -- 2.20.1