Commit 2f80d502 authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

KVM: x86: fix shift out of bounds reported by UBSAN 



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: default avatar <syzbot+e87846c48bf72bc85311@syzkaller.appspotmail.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent b268b6f0

arch/x86/kvm/mmu.h

+1 −1
Original line number Diff line number Diff line
@@ -49,7 +49,7 @@ 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_value, u64 access_mask);