From 506cfba9e726ab6842883fdd567a9a7c467e7492 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 14 Jul 2016 18:54:17 +0200 Subject: [PATCH] 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 --- virt/kvm/kvm_main.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index dd25346ec356..ce3d8e5be73e 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -3050,6 +3050,7 @@ static int kvm_dev_ioctl_create_vm(unsigned long type) { int r; struct kvm *kvm; + struct file *file; kvm = kvm_create_vm(type); if (IS_ERR(kvm)) @@ -3061,17 +3062,25 @@ static int kvm_dev_ioctl_create_vm(unsigned long type) 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; } -- 2.20.1