nvme: ensure subsystem reset is single threaded
commit 1e866afd4bcdd01a70a5eddb4371158d3035ce03 upstream.
The subsystem reset writes to a register, so we have to ensure the
device state is capable of handling that otherwise the driver may access
unmapped registers. Use the state machine to ensure the subsystem reset
doesn't try to write registers on a device already undergoing this type
of reset.
BUG=b/246924114
TEST=presubmit,validation
RELEASE_NOTE=Fixes CVE-2022-3169 in the Linux kernel.
cos-patch: security-moderate
Link: https://bugzilla.kernel.org/show_bug.cgi?id=214771
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change-Id: If1bce9edc8120cc4dbe1f913bb22692756d33456
Reviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/39448
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
Reviewed-by: Oleksandr Tymoshenko <ovt@google.com>
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index 75a7e7b..7f52b2b 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -558,11 +558,23 @@
static inline void nvme_should_fail(struct request *req) {}
#endif
+bool nvme_wait_reset(struct nvme_ctrl *ctrl);
+int nvme_try_sched_reset(struct nvme_ctrl *ctrl);
+
static inline int nvme_reset_subsystem(struct nvme_ctrl *ctrl)
{
+ int ret;
+
if (!ctrl->subsystem)
return -ENOTTY;
- return ctrl->ops->reg_write32(ctrl, NVME_REG_NSSR, 0x4E564D65);
+ if (!nvme_wait_reset(ctrl))
+ return -EBUSY;
+
+ ret = ctrl->ops->reg_write32(ctrl, NVME_REG_NSSR, 0x4E564D65);
+ if (ret)
+ return ret;
+
+ return nvme_try_sched_reset(ctrl);
}
/*
@@ -650,7 +662,6 @@
void nvme_cancel_admin_tagset(struct nvme_ctrl *ctrl);
bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,
enum nvme_ctrl_state new_state);
-bool nvme_wait_reset(struct nvme_ctrl *ctrl);
int nvme_disable_ctrl(struct nvme_ctrl *ctrl);
int nvme_enable_ctrl(struct nvme_ctrl *ctrl);
int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl);
@@ -734,7 +745,6 @@
void nvme_stop_keep_alive(struct nvme_ctrl *ctrl);
int nvme_reset_ctrl(struct nvme_ctrl *ctrl);
int nvme_reset_ctrl_sync(struct nvme_ctrl *ctrl);
-int nvme_try_sched_reset(struct nvme_ctrl *ctrl);
int nvme_delete_ctrl(struct nvme_ctrl *ctrl);
void nvme_queue_scan(struct nvme_ctrl *ctrl);
int nvme_get_log(struct nvme_ctrl *ctrl, u32 nsid, u8 log_page, u8 lsp, u8 csi,
