[PATCH] KVM: Add missing debugfs cleanup in kvm_init error path

[Steffen Eiden <seiden@linux.ibm.com>]

If any initialization after kvm_init_debug() fails the cleanup code did
not remove the debugfs entries. Therefore, the corresponding debugfs
entries where still alive but the backing fops are already freed,
creating a use-after-free scenario. Fix this by removing the debugfs
entries if vfio init fails.

Fixes: 2b0128127373 ("KVM: Register /dev/kvm as the _very_ last thing during initialization")
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
 virt/kvm/kvm_main.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index e44c20c04961..d4420ebfd972 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -6559,6 +6559,7 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align, struct module *module)
 err_gmem:
 	kvm_vfio_ops_exit();
 err_vfio:
+	debugfs_remove_recursive(kvm_debugfs_dir);
 	kvm_async_pf_deinit();
 err_async_pf:
 	kvm_irqfd_exit();
-- 
2.53.0