Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

nvme-apple: Destroy the admin queue on removal

The admin queue is allocated with blk_mq_alloc_queue() but never destroyed. nvme_free_ctrl() only drops the last reference and blk_mq_exit_queue() and blk_sync_queue() never run: the hctx is never moved to q->unused_hctx_list and the timeout timer and work stay armed on a queue that is about to be freed which will eventually oops inside blk_mq_timeout_work().

This can only be triggered when the controller fails to come up and is then immediately torn down again which is why no one ever ran into this before.

Let's just copy what the pcie driver does: unquiesce and destroy the admin queue before nvme_uninit_ctrl().

With this the following WARN followed by a panic no longer happens:

WARNING: block/blk-mq.c:4390 at blk_mq_release+0x194/0x238, CPU#4: kworker/u34:4/119 CPU: 4 UID: 0 PID: 119 Comm: kworker/u34:4 Not tainted 7.2.0-rc1-dirty #248 PREEMPT Hardware name: Apple Mac mini (M1, 2020) (DT) Workqueue: nvme-wq apple_nvme_remove_dead_ctrl_work pstate: 61400005 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) pc : blk_mq_release+0x194/0x238 lr : blk_mq_release+0x58/0x238 sp : ffffc000833a3b50 x29: ffffc000833a3b50 x28: ffff80001d0450f8 x27: ffff800020c95200 x26: 0000000000000088 x25: 0000000000000000 x24: ffff800020f36805 x23: 0000000000000000 x22: ffffc00081a86878 x21: ffff800020be9c60 x20: 0000000000000000 x19: ffff800022501698 x18: 00…