From 8c1624b63a7d24142a2bbc3a5ee7e95f004ea36e Mon Sep 17 00:00:00 2001 From: Sagi Grimberg Date: Thu, 20 Feb 2025 13:18:30 +0200 Subject: [PATCH] nvme-tcp: fix possible UAF in nvme_tcp_poll nvme_tcp_poll() may race with the send path error handler because it may complete the request while it is actively being polled for completion, resulting in a UAF panic [1]: We should make sure to stop polling when we see an error when trying to read from the socket. Hence make sure to propagate the error so that the block layer breaks the polling cycle. [1]: -- [35665.692310] nvme nvme2: failed to send request -13 [35665.702265] nvme nvme2: unsupported pdu type (3) [35665.702272] BUG: kernel NULL pointer dereference, address: 0000000000000000 [35665.702542] nvme nvme2: queue 1 receive failed: -22 [35665.703209] #PF: supervisor write access in kernel mode [35665.703213] #PF: error_code(0x0002) - not-present page [35665.703214] PGD 8000003801cce067 P4D 8000003801cce067 PUD 37e6f79067 PMD 0 [35665.703220] Oops: 0002 [#1] SMP PTI [35665.703658] nvme nvme2: starting error recovery [35665.705809] Hardware name: Inspur aaabbb/YZMB-00882-104, BIOS 4.1.26 09/22/2022 [35665.705812] Workqueue: kblockd blk_mq_requeue_work [35665.709172] RIP: 0010:_raw_spin_lock+0xc/0x30 [35665.715788] Call Trace: [35665.716201] [35665.716613] ? show_trace_log_lvl+0x1c1/0x2d9 [35665.717049] ? show_trace_log_lvl+0x1c1/0x2d9 [35665.717457] ? blk_mq_request_bypass_insert+0x2c/0xb0 [35665.717950] ? __die_body.cold+0x8/0xd [35665.718361] ? page_fault_oops+0xac/0x140 [35665.718749] ? blk_mq_start_request+0x30/0xf0 [35665.719144] ? nvme_tcp_queue_rq+0xc7/0x170 [nvme_tcp] [35665.719547] ? exc_page_fault+0x62/0x130 [35665.719938] ? asm_exc_page_fault+0x22/0x30 [35665.720333] ? _raw_spin_lock+0xc/0x30 [35665.720723] blk_mq_request_bypass_insert+0x2c/0xb0 [35665.721101] blk_mq_requeue_work+0xa5/0x180 [35665.721451] process_one_work+0x1e8/0x390 [35665.721809] worker_thread+0x53/0x3d0 [35665.722159] ? process_one_work+0x390/0x390 [35665.722501] kthread+0x124/0x150 [35665.722849] ? set_kthread_struct+0x50/0x50 [35665.723182] ret_from_fork+0x1f/0x30 Reported-by: Zhang Guanghui Signed-off-by: Sagi Grimberg Reviewed-by: Chaitanya Kulkarni Signed-off-by: Keith Busch --- drivers/nvme/host/tcp.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c index 8a9131c95a3d..8c14018201db 100644 --- a/drivers/nvme/host/tcp.c +++ b/drivers/nvme/host/tcp.c @@ -2699,6 +2699,7 @@ static int nvme_tcp_poll(struct blk_mq_hw_ctx *hctx, struct io_comp_batch *iob) { struct nvme_tcp_queue *queue = hctx->driver_data; struct sock *sk = queue->sock->sk; + int ret; if (!test_bit(NVME_TCP_Q_LIVE, &queue->flags)) return 0; @@ -2706,9 +2707,9 @@ static int nvme_tcp_poll(struct blk_mq_hw_ctx *hctx, struct io_comp_batch *iob) set_bit(NVME_TCP_Q_POLLING, &queue->flags); if (sk_can_busy_loop(sk) && skb_queue_empty_lockless(&sk->sk_receive_queue)) sk_busy_loop(sk, true); - nvme_tcp_try_recv(queue); + ret = nvme_tcp_try_recv(queue); clear_bit(NVME_TCP_Q_POLLING, &queue->flags); - return queue->nr_cqe; + return ret < 0 ? ret : queue->nr_cqe; } static int nvme_tcp_get_address(struct nvme_ctrl *ctrl, char *buf, int size) -- 2.49.0