[PATCH RFC 36/41] nvmet: refuse files on pseudo filesystems as namespace backing files

[Christian Brauner]

The file backend takes any path that isn't a block device. With
buffered_io=1 that includes files on procfs or sysfs which then get read
and written by a kernel worker on behalf of the host. Refuse files on
pseudo filesystems just like loop does.

Signed-off-by: Christian Brauner (Amutable) <brauner@xxxxxxxxxx>
---
 drivers/nvme/target/io-cmd-file.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/nvme/target/io-cmd-file.c b/drivers/nvme/target/io-cmd-file.c
index dfa8aa46188c..71c69bac5394 100644
--- a/drivers/nvme/target/io-cmd-file.c
+++ b/drivers/nvme/target/io-cmd-file.c
@@ -52,6 +52,11 @@ int nvmet_file_ns_enable(struct nvmet_ns *ns)
 		goto err;
 	}
 
+	if (file_is_pseudo(ns->file)) {
+		ret = -EINVAL;
+		goto err;
+	}
+
 	nvmet_file_ns_revalidate(ns);
 
 	/*

-- 
2.53.0