linux/virt
Jim Mattson e713956a01 kvm: Disallow wraparound in kvm_gfn_to_hva_cache_init
commit f1b9dd5eb8 upstream.

Previously, in the case where (gpa + len) wrapped around, the entire
region was not validated, as the comment claimed. It doesn't actually
seem that wraparound should be allowed here at all.

Furthermore, since some callers don't check the return code from this
function, it seems prudent to clear ghc->memslot in the event of an
error.

Fixes: 8f964525a1 ("KVM: Allow cross page reads and writes from cached translations.")
Reported-by: Cfir Cohen <cfir@google.com>
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Cfir Cohen <cfir@google.com>
Reviewed-by: Marc Orr <marcorr@google.com>
Cc: Andrew Honig <ahonig@google.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
History 2019-04-04 16:14:04 +01:00
..
kvm kvm: Disallow wraparound in kvm_gfn_to_hva_cache_init 2019-04-04 16:14:04 +01:00