[PATCH v2] nvme: disallow passthru cmd from targeting a nsid != nsid of the block dev

[Niklas Cassel]

From: Niklas Cassel <niklas.cassel at wdc.com>

When a passthru command targets a specific namespace, the ns parameter to
nvme_user_cmd()/nvme_user_cmd64() is set. However, there is currently no
validation that the nsid specified in the passthru command targets the
namespace/nsid represented by the block device that the ioctl was
performed on.

Add a check that validates that the nsid in the passthru command matches
that of the supplied namespace.

Signed-off-by: Niklas Cassel <niklas.cassel at wdc.com>
---
Changes since v1:
-Added error print.

 drivers/nvme/host/core.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index f13eb4ded95f..a50352ea3f7b 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -1599,6 +1599,12 @@ static int nvme_user_cmd(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
 		return -EFAULT;
 	if (cmd.flags)
 		return -EINVAL;
+	if (ns && cmd.nsid != ns->head->ns_id) {
+		dev_err(ctrl->device,
+			"%s: nsid (%u) in cmd does not match nsid (%u) of namespace\n",
+			current->comm, cmd.nsid, ns->head->ns_id);
+		return -EINVAL;
+	}
 
 	memset(&c, 0, sizeof(c));
 	c.common.opcode = cmd.opcode;
@@ -1643,6 +1649,12 @@ static int nvme_user_cmd64(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
 		return -EFAULT;
 	if (cmd.flags)
 		return -EINVAL;
+	if (ns && cmd.nsid != ns->head->ns_id) {
+		dev_err(ctrl->device,
+			"%s: nsid (%u) in cmd does not match nsid (%u) of namespace\n",
+			current->comm, cmd.nsid, ns->head->ns_id);
+		return -EINVAL;
+	}
 
 	memset(&c, 0, sizeof(c));
 	c.common.opcode = cmd.opcode;
-- 
2.30.2