| Message ID | 20191211204753.242298-4-pomonis@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: x86: Extend Spectre-v1 mitigation | expand |
On Wed, Dec 11, 2019 at 12:48 PM Marios Pomonis <pomonis@google.com> wrote: > > This fixes a Spectre-v1/L1TF vulnerability in picdev_write(). > It replaces index computations based on the (attacked-controlled) port > number with constants through a minor refactoring. > > Fixes: commit 85f455f7ddbe ("KVM: Add support for in-kernel PIC emulation") > > Signed-off-by: Nick Finco <nifi@google.com> > Signed-off-by: Marios Pomonis <pomonis@google.com> > Reviewed-by: Andrew Honig <ahonig@google.com> > Cc: stable@vger.kernel.org Reviewed-by: Jim Mattson <jmattson@google.com>
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c index 8b38bb4868a6..629a09ca9860 100644 --- a/arch/x86/kvm/i8259.c +++ b/arch/x86/kvm/i8259.c @@ -460,10 +460,14 @@ static int picdev_write(struct kvm_pic *s, switch (addr) { case 0x20: case 0x21: + pic_lock(s); + pic_ioport_write(&s->pics[0], addr, data); + pic_unlock(s); + break; case 0xa0: case 0xa1: pic_lock(s); - pic_ioport_write(&s->pics[addr >> 7], addr, data); + pic_ioport_write(&s->pics[1], addr, data); pic_unlock(s); break; case 0x4d0:
This fixes a Spectre-v1/L1TF vulnerability in picdev_write(). It replaces index computations based on the (attacked-controlled) port number with constants through a minor refactoring. Fixes: commit 85f455f7ddbe ("KVM: Add support for in-kernel PIC emulation") Signed-off-by: Nick Finco <nifi@google.com> Signed-off-by: Marios Pomonis <pomonis@google.com> Reviewed-by: Andrew Honig <ahonig@google.com> Cc: stable@vger.kernel.org --- arch/x86/kvm/i8259.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)