debugfs_lookup() doesn't like it if it is passed an illegal name pointer, or if the filesystem isn't even initialized yet. If either of these happen, it will crash the system, so fix it up by properly testing for valid input and that we are up and running before trying to find a file in the filesystem.
Reported-by: Michael Walle michael@walle.cc Tested-by: Michael Walle michael@walle.cc Tested-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 | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c index 2fcf66473436..bbeb563cbe78 100644 --- a/fs/debugfs/inode.c +++ b/fs/debugfs/inode.c @@ -297,7 +297,7 @@ struct dentry *debugfs_lookup(const char *name, struct dentry *parent) { struct dentry *dentry;
- if (IS_ERR(parent)) + if (!debugfs_initialized() || IS_ERR_OR_NULL(name) || IS_ERR(parent)) return NULL;
if (!parent)