From: Sagi Grimberg sagi@grimberg.me
[ Upstream commit 88eaba80328b31ef81813a1207b4056efd7006a6 ]
When we allocate a nvme-tcp queue, we set the data_ready callback before we actually need to use it. This creates the potential that if a stray controller sends us data on the socket before we connect, we can trigger the io_work and start consuming the socket.
In this case reported: we failed to allocate one of the io queues, and as we start releasing the queues that we already allocated, we get a UAF [1] from the io_work which is running before it should really.
Fix this by setting the socket ops callbacks only before we start the queue, so that we can't accidentally schedule the io_work in the initialization phase before the queue started. While we are at it, rename nvme_tcp_restore_sock_calls to pair with nvme_tcp_setup_sock_ops.
[1]: [16802.107284] nvme nvme4: starting error recovery [16802.109166] nvme nvme4: Reconnecting in 10 seconds... [16812.173535] nvme nvme4: failed to connect socket: -111 [16812.173745] nvme nvme4: Failed reconnect attempt 1 [16812.173747] nvme nvme4: Reconnecting in 10 seconds... [16822.413555] nvme nvme4: failed to connect socket: -111 [16822.413762] nvme nvme4: Failed reconnect attempt 2 [16822.413765] nvme nvme4: Reconnecting in 10 seconds... [16832.661274] nvme nvme4: creating 32 I/O queues. [16833.919887] BUG: kernel NULL pointer dereference, address: 0000000000000088 [16833.920068] nvme nvme4: Failed reconnect attempt 3 [16833.920094] #PF: supervisor write access in kernel mode [16833.920261] nvme nvme4: Reconnecting in 10 seconds... [16833.920368] #PF: error_code(0x0002) - not-present page [16833.921086] Workqueue: nvme_tcp_wq nvme_tcp_io_work [nvme_tcp] [16833.921191] RIP: 0010:_raw_spin_lock_bh+0x17/0x30 ... [16833.923138] Call Trace: [16833.923271] <TASK> [16833.923402] lock_sock_nested+0x1e/0x50 [16833.923545] nvme_tcp_try_recv+0x40/0xa0 [nvme_tcp] [16833.923685] nvme_tcp_io_work+0x68/0xa0 [nvme_tcp] [16833.923824] process_one_work+0x1e8/0x390 [16833.923969] worker_thread+0x53/0x3d0 [16833.924104] ? process_one_work+0x390/0x390 [16833.924240] kthread+0x124/0x150 [16833.924376] ? set_kthread_struct+0x50/0x50 [16833.924518] ret_from_fork+0x1f/0x30 [16833.924655] </TASK>
Reported-by: Yanjun Zhang zhangyanjun@cestc.cn Signed-off-by: Sagi Grimberg sagi@grimberg.me Tested-by: Yanjun Zhang zhangyanjun@cestc.com Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nvme/host/tcp.c | 46 +++++++++++++++++++++++------------------ 1 file changed, 26 insertions(+), 20 deletions(-)
diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c index 1ca52ac163c2f..2c15412649bab 100644 --- a/drivers/nvme/host/tcp.c +++ b/drivers/nvme/host/tcp.c @@ -1605,22 +1605,7 @@ static int nvme_tcp_alloc_queue(struct nvme_ctrl *nctrl, int qid) if (ret) goto err_init_connect;
- queue->rd_enabled = true; set_bit(NVME_TCP_Q_ALLOCATED, &queue->flags); - nvme_tcp_init_recv_ctx(queue); - - write_lock_bh(&queue->sock->sk->sk_callback_lock); - queue->sock->sk->sk_user_data = queue; - queue->state_change = queue->sock->sk->sk_state_change; - queue->data_ready = queue->sock->sk->sk_data_ready; - queue->write_space = queue->sock->sk->sk_write_space; - queue->sock->sk->sk_data_ready = nvme_tcp_data_ready; - queue->sock->sk->sk_state_change = nvme_tcp_state_change; - queue->sock->sk->sk_write_space = nvme_tcp_write_space; -#ifdef CONFIG_NET_RX_BUSY_POLL - queue->sock->sk->sk_ll_usec = 1; -#endif - write_unlock_bh(&queue->sock->sk->sk_callback_lock);
return 0;
@@ -1640,7 +1625,7 @@ static int nvme_tcp_alloc_queue(struct nvme_ctrl *nctrl, int qid) return ret; }
-static void nvme_tcp_restore_sock_calls(struct nvme_tcp_queue *queue) +static void nvme_tcp_restore_sock_ops(struct nvme_tcp_queue *queue) { struct socket *sock = queue->sock;
@@ -1655,7 +1640,7 @@ static void nvme_tcp_restore_sock_calls(struct nvme_tcp_queue *queue) static void __nvme_tcp_stop_queue(struct nvme_tcp_queue *queue) { kernel_sock_shutdown(queue->sock, SHUT_RDWR); - nvme_tcp_restore_sock_calls(queue); + nvme_tcp_restore_sock_ops(queue); cancel_work_sync(&queue->io_work); }
@@ -1673,21 +1658,42 @@ static void nvme_tcp_stop_queue(struct nvme_ctrl *nctrl, int qid) mutex_unlock(&queue->queue_lock); }
+static void nvme_tcp_setup_sock_ops(struct nvme_tcp_queue *queue) +{ + write_lock_bh(&queue->sock->sk->sk_callback_lock); + queue->sock->sk->sk_user_data = queue; + queue->state_change = queue->sock->sk->sk_state_change; + queue->data_ready = queue->sock->sk->sk_data_ready; + queue->write_space = queue->sock->sk->sk_write_space; + queue->sock->sk->sk_data_ready = nvme_tcp_data_ready; + queue->sock->sk->sk_state_change = nvme_tcp_state_change; + queue->sock->sk->sk_write_space = nvme_tcp_write_space; +#ifdef CONFIG_NET_RX_BUSY_POLL + queue->sock->sk->sk_ll_usec = 1; +#endif + write_unlock_bh(&queue->sock->sk->sk_callback_lock); +} + static int nvme_tcp_start_queue(struct nvme_ctrl *nctrl, int idx) { struct nvme_tcp_ctrl *ctrl = to_tcp_ctrl(nctrl); + struct nvme_tcp_queue *queue = &ctrl->queues[idx]; int ret;
+ queue->rd_enabled = true; + nvme_tcp_init_recv_ctx(queue); + nvme_tcp_setup_sock_ops(queue); + if (idx) ret = nvmf_connect_io_queue(nctrl, idx); else ret = nvmf_connect_admin_queue(nctrl);
if (!ret) { - set_bit(NVME_TCP_Q_LIVE, &ctrl->queues[idx].flags); + set_bit(NVME_TCP_Q_LIVE, &queue->flags); } else { - if (test_bit(NVME_TCP_Q_ALLOCATED, &ctrl->queues[idx].flags)) - __nvme_tcp_stop_queue(&ctrl->queues[idx]); + if (test_bit(NVME_TCP_Q_ALLOCATED, &queue->flags)) + __nvme_tcp_stop_queue(queue); dev_err(nctrl->device, "failed to connect queue: %d ret=%d\n", idx, ret); }