From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CB5654772A1; Mon, 31 Aug 2026 13:53:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788184393; cv=none; b=eJJiuSAlbWlvGm3NVHPt7h0k7mTvQt5cmoa+2ovNvnv6Xrt9z2wN/H5JUomUP0cIrndmx39JwX/y8JbJY8Fr9+NDNuYEJYCuiHEYpVeCWa0bpkt1Hi4OGs7TDktQoQESWmuymaXe/2vPQxHRIQJjUFtPR2Mx93ytO5sJxTIlFgw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788184393; c=relaxed/simple; bh=jaiZojmVgRA2//LeacbxvlJFMMmnYw5Ub0DqqIIaSdk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Xfj3tiTFbKKG7+5hQkg+Twp4m5TqXyFrnqg1eW/O0nSc3aykIdbEa5ve0YpJ0oxP9ZPw0clzCFjJ8aaYAlwcQ6eDOdEKvWbIICtMG1n0v7Wf8ATAfugcw9e6SzsHm8Ojo64E+thXRANlGjZuGhm+u4eH616j0dMxmgN0qapMtgk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=pdJec1kC; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="pdJec1kC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DF3F61F000E9; Mon, 31 Aug 2026 13:53:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788184391; bh=muJmwj/ajGrX2Fw26BW7RwoLW1C927G8vNUnafWOnRs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=pdJec1kCAXKVVkA4aYdP9sqArF0mASpS65UNkFfCZuWDHICwjufWUSlXyPfuIRFv2 j8ShqgWuZPadRELSl7DzyPCIBdZR9wfhmjee8S0pN3szSsipsEDjavoa28/bxZNIby R2+ep+ZpFy70EgcD/hew32AoANQOjDypGSAXCu/s= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Christian Borntraeger , Claudio Imbrenda Subject: [PATCH 6.12 90/99] KVM: s390: vsie: zero stale crypto bits Date: Mon, 31 Aug 2026 15:34:59 +0200 Message-ID: <20260831133404.263033705@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260831133359.740409777@linuxfoundation.org> References: <20260831133359.740409777@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Christian Borntraeger commit 34d5b5b646c91cfb9338d7a12c955a70ffb8c66b upstream. When shadowing crypto access bits from a format0 apcb (crycb 0 or 1), the bits 64..255 are unchanged from whatever is in the vsie page in the crycb and thus in the apcb. This gives a nested guest potential access to a device no longer available. Zero out the remaining bits. Fixes: 6b79de4b056e ("KVM: s390: vsie: allow guest FORMAT-1 CRYCB on host FORMAT-2") Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger Reviewed-by: Claudio Imbrenda Signed-off-by: Claudio Imbrenda Message-ID: <20260811153738.206885-3-borntraeger@linux.ibm.com> Signed-off-by: Greg Kroah-Hartman --- arch/s390/kvm/vsie.c | 1 + 1 file changed, 1 insertion(+) --- a/arch/s390/kvm/vsie.c +++ b/arch/s390/kvm/vsie.c @@ -150,6 +150,7 @@ static int setup_apcb10(struct kvm_vcpu sizeof(struct kvm_s390_apcb0))) return -EFAULT; + memset(apcb_s, 0, sizeof(*apcb_s)); apcb_s->apm[0] = apcb_h->apm[0] & tmp.apm[0]; apcb_s->aqm[0] = apcb_h->aqm[0] & tmp.aqm[0] & 0xffff000000000000UL; apcb_s->adm[0] = apcb_h->adm[0] & tmp.adm[0] & 0xffff000000000000UL;