From: Maxim Levitsky Date: Thu, 12 May 2022 10:14:20 +0000 (+0300) Subject: KVM: x86: fix typo in __try_cmpxchg_user causing non-atomicness X-Git-Tag: howlett/maple/20220722_2~444^2~27 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=33fbe6befa622c082f7d417896832856814bdde0;p=users%2Fjedix%2Flinux-maple.git KVM: x86: fix typo in __try_cmpxchg_user causing non-atomicness This shows up as a TDP MMU leak when running nested. Non-working cmpxchg on L0 relies makes L1 install two different shadow pages under same spte, and one of them is leaked. Fixes: 1c2361f667f36 ("KVM: x86: Use __try_cmpxchg_user() to emulate atomic accesses") Signed-off-by: Maxim Levitsky Message-Id: <20220512101420.306759-1-mlevitsk@redhat.com> Reviewed-by: Sean Christopherson Reviewed-by: Vitaly Kuznetsov Signed-off-by: Paolo Bonzini --- diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index ba4faeb324374..8f2108e86b02f 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7315,7 +7315,7 @@ static int emulator_cmpxchg_emulated(struct x86_emulate_ctxt *ctxt, goto emul_write; hva = kvm_vcpu_gfn_to_hva(vcpu, gpa_to_gfn(gpa)); - if (kvm_is_error_hva(addr)) + if (kvm_is_error_hva(hva)) goto emul_write; hva += offset_in_page(gpa);