diff options
| author | Steve Wise <swise@opengridcomputing.com> | 2018-08-31 16:16:03 +0200 |
|---|---|---|
| committer | Jason Gunthorpe <jgg@mellanox.com> | 2018-09-12 23:43:15 +0200 |
| commit | 67e3816842fe6414d629c7515b955952ec40c7d7 (patch) | |
| tree | d333ccc515e5c71ff1657854c863573b7ff506d1 | |
| parent | cxgb4: fix abort_req_rss6 struct (diff) | |
| download | linux-67e3816842fe6414d629c7515b955952ec40c7d7.tar.xz linux-67e3816842fe6414d629c7515b955952ec40c7d7.zip | |
RDMA/uverbs: Atomically flush and mark closed the comp event queue
Currently a uverbs completion event queue is flushed of events in
ib_uverbs_comp_event_close() with the queue spinlock held and then
released. Yet setting ev_queue->is_closed is not set until later in
uverbs_hot_unplug_completion_event_file().
In between the time ib_uverbs_comp_event_close() releases the lock and
uverbs_hot_unplug_completion_event_file() acquires the lock, a completion
event can arrive and be inserted into the event queue by
ib_uverbs_comp_handler().
This can cause a "double add" list_add warning or crash depending on the
kernel configuration, or a memory leak because the event is never dequeued
since the queue is already closed down.
So add setting ev_queue->is_closed = 1 to ib_uverbs_comp_event_close().
Cc: stable@vger.kernel.org
Fixes: 1e7710f3f656 ("IB/core: Change completion channel to use the reworked objects schema")
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
| -rw-r--r-- | drivers/infiniband/core/uverbs_main.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c index 6d974e2363df..50152c1b1004 100644 --- a/drivers/infiniband/core/uverbs_main.c +++ b/drivers/infiniband/core/uverbs_main.c @@ -440,6 +440,7 @@ static int ib_uverbs_comp_event_close(struct inode *inode, struct file *filp) list_del(&entry->obj_list); kfree(entry); } + file->ev_queue.is_closed = 1; spin_unlock_irq(&file->ev_queue.lock); uverbs_close_fd(filp); |