From 0191e7405b687339a5540c1562acdecefd70eb3f Mon Sep 17 00:00:00 2001 From: James Smart Date: Wed, 13 Mar 2019 18:55:03 +0100 Subject: nvmet-fc: fix issues with targetport assoc_list list walking There are two changes: 1) The logic in the __nvmet_fc_free_assoc() routine is bad. It uses "safe" routines assuming pointers will come back valid. However, the intervening next structure being linked can be removed from the list and the resulting safe pointers are bad, resulting in NULL ptrs being hit. Correct by scheduling a work element to perform the association delete, which can be done while under lock. 2) Prior patch that added the work element scheduling left a possible reference on the object if the work element couldn't be scheduled. Correct by doing the put on a failing schedule_work() call. Signed-off-by: Nigel Kirkland Signed-off-by: James Smart Reviewed-by: Ewan D. Milne Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- drivers/nvme/target/fc.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'drivers/nvme/target/fc.c') diff --git a/drivers/nvme/target/fc.c b/drivers/nvme/target/fc.c index 1e9654f04c60..6b7bbf39fa06 100644 --- a/drivers/nvme/target/fc.c +++ b/drivers/nvme/target/fc.c @@ -1143,10 +1143,8 @@ __nvmet_fc_free_assocs(struct nvmet_fc_tgtport *tgtport) &tgtport->assoc_list, a_list) { if (!nvmet_fc_tgt_a_get(assoc)) continue; - spin_unlock_irqrestore(&tgtport->lock, flags); - nvmet_fc_delete_target_assoc(assoc); - nvmet_fc_tgt_a_put(assoc); - spin_lock_irqsave(&tgtport->lock, flags); + if (!schedule_work(&assoc->del_work)) + nvmet_fc_tgt_a_put(assoc); } spin_unlock_irqrestore(&tgtport->lock, flags); } @@ -1185,7 +1183,8 @@ nvmet_fc_delete_ctrl(struct nvmet_ctrl *ctrl) nvmet_fc_tgtport_put(tgtport); if (found_ctrl) { - schedule_work(&assoc->del_work); + if (!schedule_work(&assoc->del_work)) + nvmet_fc_tgt_a_put(assoc); return; } -- cgit v1.2.3-59-g8ed1b