Forwarded: Re: [syzbot] [block?] general protection fault in blk_mq_quiesce_queue

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Subject: Re: [syzbot] [block?] general protection fault in blk_mq_quiesce_queue
Author: nenkov2004@xxxxxxxxx

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
master

diff --git a/drivers/nvme/host/sysfs.c b/drivers/nvme/host/sysfs.c
--- a/drivers/nvme/host/sysfs.c
+++ b/drivers/nvme/host/sysfs.c
@@ -17,6 +17,14 @@ static ssize_t nvme_sysfs_reset(struct device *dev,
 {
 	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
 	int ret;

+	/*
+	 * nvme_add_ctrl() publishes this attribute before some transports have
+	 * finished creating their queues. Do not let userspace reset a controller
+	 * while it is still being initialized.
+	 */
+	if (nvme_ctrl_state(ctrl) != NVME_CTRL_LIVE)
+		return -EBUSY;
+
 	ret = nvme_reset_ctrl_sync(ctrl);
 	if (ret < 0)
 		return ret;