From: Nina Schoetterl-Glausch Date: Tue, 19 Dec 2023 14:08:50 +0000 (+0100) Subject: KVM: s390: vsie: Fix STFLE interpretive execution identification X-Git-Tag: v6.8-rc1~78^2~14^2~2 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=2731d605d5478052a10ac5a7c80f7aa7e1788cc5;p=thirdparty%2Flinux.git KVM: s390: vsie: Fix STFLE interpretive execution identification STFLE can be interpretively executed. This occurs when the facility list designation is unequal to zero. Perform the check before applying the address mask instead of after. Fixes: 66b630d5b7f2 ("KVM: s390: vsie: support STFLE interpretation") Reviewed-by: Claudio Imbrenda Acked-by: David Hildenbrand Signed-off-by: Nina Schoetterl-Glausch Reviewed-by: Christian Borntraeger Reviewed-by: Janosch Frank Link: https://lore.kernel.org/r/20231219140854.1042599-2-nsg@linux.ibm.com Signed-off-by: Janosch Frank Message-ID: <20231219140854.1042599-2-nsg@linux.ibm.com> --- diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c index 02dcbe82a8e51..3cf95bc0401de 100644 --- a/arch/s390/kvm/vsie.c +++ b/arch/s390/kvm/vsie.c @@ -988,10 +988,15 @@ static void retry_vsie_icpt(struct vsie_page *vsie_page) static int handle_stfle(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) { struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; - __u32 fac = READ_ONCE(vsie_page->scb_o->fac) & 0x7ffffff8U; + __u32 fac = READ_ONCE(vsie_page->scb_o->fac); if (fac && test_kvm_facility(vcpu->kvm, 7)) { retry_vsie_icpt(vsie_page); + /* + * The facility list origin (FLO) is in bits 1 - 28 of the FLD + * so we need to mask here before reading. + */ + fac = fac & 0x7ffffff8U; if (read_guest_real(vcpu, fac, &vsie_page->fac, sizeof(vsie_page->fac))) return set_validity_icpt(scb_s, 0x1090U);