diff mbox series

[2/2] debugfs: do not attempt to create a new file before the filesystem is initalized

Message ID 20210218100818.3622317-2-gregkh@linuxfoundation.org
State Accepted
Commit 56348560d495d2501e87db559a61de717cd3ab02
Headers show
Series None | expand

Commit Message

Greg Kroah-Hartman Feb. 18, 2021, 10:08 a.m. UTC
Some subsystems want to add debugfs files at early boot, way before
debugfs is initialized.  This seems to work somehow as the vfs layer
will not allow it to happen, but let's be explicit and test to ensure we
are properly up and running before allowing files to be created.

Reported-by: Michael Walle <michael@walle.cc>
Reported-by: Marc Zyngier <maz@kernel.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 fs/debugfs/inode.c | 3 +++
 1 file changed, 3 insertions(+)
diff mbox series

Patch

diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index bbeb563cbe78..86c7f0489620 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -318,6 +318,9 @@  static struct dentry *start_creating(const char *name, struct dentry *parent)
 	if (!(debugfs_allow & DEBUGFS_ALLOW_API))
 		return ERR_PTR(-EPERM);
 
+	if (!debugfs_initialized())
+		return ERR_PTR(-ENOENT);
+
 	pr_debug("creating file '%s'\n", name);
 
 	if (IS_ERR(parent))