From: Paolo Bonzini pbonzini@redhat.com
commit 2f80d502d627f30257ba7e3655e71c373b7d1a5a upstream.
Since we know that e >= s, we can reassociate the left shift, changing the shifted number from 1 to 2 in exchange for decreasing the right hand side by 1.
Reported-by: syzbot+e87846c48bf72bc85311@syzkaller.appspotmail.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/x86/kvm/mmu.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/x86/kvm/mmu.h +++ b/arch/x86/kvm/mmu.h @@ -48,7 +48,7 @@ static inline u64 rsvd_bits(int s, int e if (e < s) return 0;
- return ((1ULL << (e - s + 1)) - 1) << s; + return ((2ULL << (e - s)) - 1) << s; }
void kvm_mmu_set_mmio_spte_mask(u64 mmio_mask, u64 mmio_value, u64 access_mask);