system/linux
system/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux synced 2024-07-22 03:01:14 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

KVM: Grab a reference to KVM for VM and vCPU stats file descriptors

Browse source 
Grab a reference to KVM prior to installing VM and vCPU stats file
descriptors to ensure the underlying VM and vCPU objects are not freed
until the last reference to any and all stats fds are dropped.

Note, the stats paths manually invoke fd_install() and so don't need to
grab a reference before creating the file.

Fixes: ce55c04945 ("KVM: stats: Support binary stats retrieval for a VCPU")
Fixes: fcfe1baedd ("KVM: stats: Support binary stats retrieval for a VM")
Reported-by: Zheng Zhang <zheng.zhang@email.ucr.edu>
Closes: https://lore.kernel.org/all/CAC_GQSr3xzZaeZt85k_RCBd5kfiOve8qXo7a81Cq53LuVQ5r=Q@mail.gmail.com
Cc: stable@vger.kernel.org
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Message-Id: <20230711230131.648752-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Sean Christopherson 2023-07-11 16:01:25 -07:00 committed by Paolo Bonzini
parent 3bcbc20942
commit eed3013faa
1 changed files with 24 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

24
virt/kvm/kvm_main.c
View file

@ -4035,8 +4035,17 @@ static ssize_t kvm_vcpu_stats_read(struct file *file, char __user *user_buffer,
sizeof(vcpu->stat), user_buffer, size, offset);
}
static int kvm_vcpu_stats_release(struct inode *inode, struct file *file)
{
struct kvm_vcpu *vcpu = file->private_data;
kvm_put_kvm(vcpu->kvm);
return 0;
}
static const struct file_operations kvm_vcpu_stats_fops = {
.read = kvm_vcpu_stats_read,
.release = kvm_vcpu_stats_release,
.llseek = noop_llseek,
};
@ -4057,6 +4066,9 @@ static int kvm_vcpu_ioctl_get_stats_fd(struct kvm_vcpu *vcpu)
put_unused_fd(fd);
return PTR_ERR(file);
}
kvm_get_kvm(vcpu->kvm);
file->f_mode |= FMODE_PREAD;
fd_install(fd, file);
@ -4701,8 +4713,17 @@ static ssize_t kvm_vm_stats_read(struct file *file, char __user *user_buffer,
sizeof(kvm->stat), user_buffer, size, offset);
}
static int kvm_vm_stats_release(struct inode *inode, struct file *file)
{
struct kvm *kvm = file->private_data;
kvm_put_kvm(kvm);
return 0;
}
static const struct file_operations kvm_vm_stats_fops = {
.read = kvm_vm_stats_read,
.release = kvm_vm_stats_release,
.llseek = noop_llseek,
};
@ -4721,6 +4742,9 @@ static int kvm_vm_ioctl_get_stats_fd(struct kvm *kvm)
put_unused_fd(fd);
return PTR_ERR(file);
}
kvm_get_kvm(kvm);
file->f_mode |= FMODE_PREAD;
fd_install(fd, file);