KVM: don't use anon_inode_getfd() before possible failures
Once anon_inode_getfd() has succeeded, it's impossible to undo
in a clean way and no, sys_close() is not usable in such cases.
Use anon_inode_getfile() and get_unused_fd_flags() to get struct file
and descriptor and do *not* install the file into the descriptor table
until after the last possible failure exit.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index dd25346..ce3d8e5 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -3050,6 +3050,7 @@
{
int r;
struct kvm *kvm;
+ struct file *file;
kvm = kvm_create_vm(type);
if (IS_ERR(kvm))
@@ -3061,17 +3062,25 @@
return r;
}
#endif
- r = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, O_RDWR | O_CLOEXEC);
+ r = get_unused_fd_flags(O_CLOEXEC);
if (r < 0) {
kvm_put_kvm(kvm);
return r;
}
+ file = anon_inode_getfile("kvm-vm", &kvm_vm_fops, kvm, O_RDWR);
+ if (IS_ERR(file)) {
+ put_unused_fd(r);
+ kvm_put_kvm(kvm);
+ return PTR_ERR(file);
+ }
if (kvm_create_vm_debugfs(kvm, r) < 0) {
- kvm_put_kvm(kvm);
+ put_unused_fd(r);
+ fput(file);
return -ENOMEM;
}
+ fd_install(r, file);
return r;
}