Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 1412cdde authored by Paolo Bonzini's avatar Paolo Bonzini Committed by Greg Kroah-Hartman
Browse files

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



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: default avatar <syzbot+e87846c48bf72bc85311@syzkaller.appspotmail.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 4dd18f78

arch/x86/kvm/mmu.h

+1 −1
Original line number Diff line number Diff line
@@ -53,7 +53,7 @@ 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);