loopfs: only show devices in their correct instance
Since loopfs devices belong to a loopfs instance they have no business
polluting the host's devtmpfs mount and should not propagate out of the
namespace they belong to.
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
unchanged
diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c
index c9017e0..77371ce 100644
--- a/drivers/base/devtmpfs.c
+++ b/drivers/base/devtmpfs.c
@@ -111,7 +111,7 @@
const char *tmp = NULL;
struct req req;
- if (!thread)
+ if (!thread || dev->no_devnode)
return 0;
req.mode = 0;
@@ -138,7 +138,7 @@
const char *tmp = NULL;
struct req req;
- if (!thread)
+ if (!thread || dev->no_devnode)
return 0;
req.name = device_get_devnode(dev, NULL, NULL, NULL, &tmp);
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 2dc53ba..5548151 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -2213,8 +2213,10 @@
disk->queue = lo->lo_queue;
sprintf(disk->disk_name, "loop%d", i);
#ifdef CONFIG_BLK_DEV_LOOPFS
- if (loopfs_i_sb(inode))
+ if (loopfs_i_sb(inode)) {
disk->user_ns = loopfs_i_sb(inode)->s_user_ns;
+ disk_to_dev(disk)->no_devnode = true;
+ }
#endif
add_disk(disk);
diff --git a/include/linux/device.h b/include/linux/device.h
index ac8e37c..c69ef1c5 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -523,6 +523,8 @@
* sync_state() callback.
* @dma_coherent: this particular device is dma coherent, even if the
* architecture supports non-coherent devices.
+ * @no_devnode: whether device nodes associated with this device are kept out
+ * of devtmpfs (e.g. due to separate filesystem)
*
* At the lowest level, every device in a Linux system is represented by an
* instance of struct device. The device structure contains the information
@@ -622,6 +624,7 @@
defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
bool dma_coherent:1;
#endif
+ bool no_devnode:1;
};
static inline struct device *kobj_to_dev(struct kobject *kobj)