diff options
| author | Maurizio Lombardi <mlombard@redhat.com> | 2023-05-11 14:07:41 +0300 |
|---|---|---|
| committer | Keith Busch <kbusch@kernel.org> | 2023-05-17 17:36:17 +0300 |
| commit | 2eb94dd56a4a4e3fe286def3e2ba207804a37345 (patch) | |
| tree | 86fb8a1b05b922e392ea8ce785a579e7bd2c9ef1 /drivers/nvme | |
| parent | 1743e5f6000901a11f4e1cd741bfa9136f3ec9b1 (diff) | |
| download | linux-2eb94dd56a4a4e3fe286def3e2ba207804a37345.tar.xz | |
nvme: do not let the user delete a ctrl before a complete initialization
If a userspace application performes a "delete_controller" command
early during the ctrl initialization, the delete operation
may race against the init code and the kernel will crash.
nvme nvme5: Connect command failed: host path error
nvme nvme5: failed to connect queue: 0 ret=880
PF: supervisor write access in kernel mode
PF: error_code(0x0002) - not-present page
blk_mq_quiesce_queue+0x18/0x90
nvme_tcp_delete_ctrl+0x24/0x40 [nvme_tcp]
nvme_do_delete_ctrl+0x7f/0x8b [nvme_core]
nvme_sysfs_delete.cold+0x8/0xd [nvme_core]
kernfs_fop_write_iter+0x124/0x1b0
new_sync_write+0xff/0x190
vfs_write+0x1ef/0x280
Fix the crash by checking the NVME_CTRL_STARTED_ONCE bit;
if it's not set it means that the nvme controller is still
in the process of getting initialized and the kernel
will return an -EBUSY error to userspace.
Set the NVME_CTRL_STARTED_ONCE later in the nvme_start_ctrl()
function, after the controller start operation is completed.
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Diffstat (limited to 'drivers/nvme')
| -rw-r--r-- | drivers/nvme/host/core.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 6c1e7d6709e0..22e9e90aa671 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -3574,6 +3574,9 @@ static ssize_t nvme_sysfs_delete(struct device *dev, { struct nvme_ctrl *ctrl = dev_get_drvdata(dev); + if (!test_bit(NVME_CTRL_STARTED_ONCE, &ctrl->flags)) + return -EBUSY; + if (device_remove_file_self(dev, attr)) nvme_delete_ctrl_sync(ctrl); return count; @@ -5034,7 +5037,7 @@ void nvme_start_ctrl(struct nvme_ctrl *ctrl) * that were missed. We identify persistent discovery controllers by * checking that they started once before, hence are reconnecting back. */ - if (test_and_set_bit(NVME_CTRL_STARTED_ONCE, &ctrl->flags) && + if (test_bit(NVME_CTRL_STARTED_ONCE, &ctrl->flags) && nvme_discovery_ctrl(ctrl)) nvme_change_uevent(ctrl, "NVME_EVENT=rediscover"); @@ -5045,6 +5048,7 @@ void nvme_start_ctrl(struct nvme_ctrl *ctrl) } nvme_change_uevent(ctrl, "NVME_EVENT=connected"); + set_bit(NVME_CTRL_STARTED_ONCE, &ctrl->flags); } EXPORT_SYMBOL_GPL(nvme_start_ctrl); |