From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (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 17A7841D217; Mon, 27 Jul 2026 15:03:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.156.1 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785164591; cv=none; b=I+yECXsYTaXmH0ZxhSKujCZMz7gZ1p4kLbIU0fBcdepFeTl7TEfxjp6i36Ww57hDQXzF/xzm72qH1Yzr2syHbeDId/RREIJkKXXvRsNUm9IjkXu0LeQ+mAsCYPB0DaEOPmWBJfu9tGWKio1MYmyQHh105f+DvFi5QTtWecuOdYc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785164591; c=relaxed/simple; bh=tvp4uu/W8ru8/7qGYerI2z3Dm1DRQ9eCsiwbl0APicw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=KQPg06tiCnWs73ch08SBVyzNONqCQ3mmVqHXeUXk6KISYliOmdoY5J3TJlSiaPKX9sVDFs7ta6nomu1Tkto7nghw8BepdzMQ/H3sdoXRSAg9EcYrytSee5TTNceduL9UgY4hO1B+Yda6f9KhcmJMwLU2/nlrY4U8ryW6Lv+bFwc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com; spf=pass smtp.mailfrom=linux.ibm.com; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b=TbG5Vzon; arc=none smtp.client-ip=148.163.156.1 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="TbG5Vzon" Received: from pps.filterd (m0360083.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 66RDmf4M2373089; Mon, 27 Jul 2026 15:03:04 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-transfer-encoding:date:from:in-reply-to:message-id :mime-version:references:subject:to; s=pp1; bh=5XGrc0w2VtIj+J+SF SnsSEV7bHbJ3Zx/+Zxj02yQk30=; b=TbG5Vzonn4HIQ/uFMa3hx1XaYqfaoeJdk 4Iya7oh20pRD5AddPvYGK7xTLJ0jo8vowUWb7SOxeFCcugcatrAJYZmoKASQogK7 6JZSul4+1SXhhw4+5TRn5I0rQyTtG9lEalcz5hSH1K+Am+BaMnfcW58Mhc1On7Zw c5lLCaZ03sHCuctcWmexVOOIYoKefJ47H+IDmurF6i1XU1mJk91gCycQOEigoasg UadEZi/mAUSscpYg1oRm9hn9YE1exXwNFBSFmt7K00fVGR5foz6BZtUQIwyRBf0q QxelS24yvz3+ukDKXHmV3cxoFmUUAA9hKFXuVbolAamgZ7ZfSlC6g== Received: from ppma22.wdc07v.mail.ibm.com (5c.69.3da9.ip4.static.sl-reverse.com [169.61.105.92]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 4fmuw78mwp-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 27 Jul 2026 15:03:04 +0000 (GMT) Received: from pps.filterd (ppma22.wdc07v.mail.ibm.com [127.0.0.1]) by ppma22.wdc07v.mail.ibm.com (8.18.1.7/8.18.1.7) with ESMTP id 66REuHPB006051; Mon, 27 Jul 2026 15:03:03 GMT Received: from smtprelay05.fra02v.mail.ibm.com ([9.218.2.225]) by ppma22.wdc07v.mail.ibm.com (PPS) with ESMTPS id 4fn7uvwy2a-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 27 Jul 2026 15:03:03 +0000 (GMT) Received: from smtpav06.fra02v.mail.ibm.com (smtpav06.fra02v.mail.ibm.com [10.20.54.105]) by smtprelay05.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 66RF2vq746006648 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 27 Jul 2026 15:02:57 GMT Received: from smtpav06.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 1C4D9200F7; Mon, 27 Jul 2026 15:02:57 +0000 (GMT) Received: from smtpav06.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 6235D200F4; Mon, 27 Jul 2026 15:02:56 +0000 (GMT) Received: from p-imbrenda.ibmuc.com (unknown [9.111.1.146]) by smtpav06.fra02v.mail.ibm.com (Postfix) with ESMTP; Mon, 27 Jul 2026 15:02:56 +0000 (GMT) From: Claudio Imbrenda To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, linux-s390@vger.kernel.org, borntraeger@de.ibm.com, frankja@linux.ibm.com, david@kernel.org, seiden@linux.ibm.com, nrb@linux.ibm.com, schlameuss@linux.ibm.com, gra@linux.ibm.com Subject: [PATCH v3 02/10] KVM: s390: Fix leaking of PGM_ADDRESSING to userspace Date: Mon, 27 Jul 2026 17:02:46 +0200 Message-ID: <20260727150254.236021-3-imbrenda@linux.ibm.com> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260727150254.236021-1-imbrenda@linux.ibm.com> References: <20260727150254.236021-1-imbrenda@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: IPZybqoOMb3KbYXSkoWjkX_7TxWYb-Jz X-Proofpoint-ORIG-GUID: IPZybqoOMb3KbYXSkoWjkX_7TxWYb-Jz X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNzI3MDE0MCBTYWx0ZWRfX8/vGxmqepprn KJvnimc2PojKX3mdzRVaADMGtN62jnlam/4o4ZHYj2l9yDW8nrYm5x902spms2QUNJESZ+jXUnt 8K4T8WBDIxdI9XfmvVoUgIe6vjgTdpn4unfsHGOeR1G0ZIuIMU2e0BxBdZoqw+2eXZzzcmMdN2p nd3iUrXNasKuVcpG3iQ58V59IbIK7VHUcRJuyJqRbZjM5FpWoEH37RnkV7XGQR9cvpbs2hYXhNr TeZres6NkNS7vYOvUApfIuAJYyonDNMqrE/+2ohKpye+iFc4KfPInFiNPb0ssTHi5HeEkaNLb/C zcWoEc8BcQhueT9WTb+wxEk5FJ7cBykC+re5ILThynSJtEkF03lLZIW2fnK3HTPZp7b6n/tNWNJ AOEtG/H5GkXDTpQT/0uX8szOYOOZtUtwzfP5nytSrXdwtpZnu7cErzfyaYnK5LvPhXwnyiTNFvG zbnndDRGwZZBhUzsebQ== X-Authority-Analysis: v=2.4 cv=SKFykuvH c=1 sm=1 tr=0 ts=6a677328 cx=c_pps a=5BHTudwdYE3Te8bg5FgnPg==:117 a=5BHTudwdYE3Te8bg5FgnPg==:17 a=RAioF0-LDSMA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=iQ6ETzBq9ecOQQE5vZCe:22 a=VnNF1IyMAAAA:8 a=GvWetJuFWLgL5UM2GZoA:9 X-Proofpoint-Spam-Info: AW1haW4tMjYwNzI3MDE0MCBTYWx0ZWRfXymqsJ4nMA058 SsoVj0aff+CfavjUnwd1JlR8Jp1Lu1KKMQGB4eP6DNr/NL5yOl7kHtJOXUWzPDfk35qhpef/tzw /RH+FcNFXaKE/eL/iZCrDfaX3wMYI/I= X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-07-27_04,2026-07-24_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 clxscore=1015 adultscore=0 lowpriorityscore=0 bulkscore=0 impostorscore=0 phishscore=0 spamscore=0 suspectscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2607270140 If kvm_s390_set_cmma_bits() is asked to set CMMA values outside of a memslot, PGM_ADDRESSING (5) is returned, instead of a negative error value. Same issue with kvm_s390_{g,s}et_skeys(), kvm_s390_keyop(), and dat_reset_reference_bit(). Fix by returning -EFAULT whenever the return value would be > 0, which is consistent with the behaviour before the gmap rewrite. Fixes: e38c884df921 ("KVM: s390: Switch to new gmap") Signed-off-by: Claudio Imbrenda --- arch/s390/kvm/dat.c | 16 ++++++++++------ arch/s390/kvm/dat.h | 2 +- arch/s390/kvm/kvm-s390.c | 16 ++++++++-------- arch/s390/kvm/priv.c | 5 +++-- 4 files changed, 22 insertions(+), 17 deletions(-) diff --git a/arch/s390/kvm/dat.c b/arch/s390/kvm/dat.c index ed4259d17629..171b61959908 100644 --- a/arch/s390/kvm/dat.c +++ b/arch/s390/kvm/dat.c @@ -755,13 +755,15 @@ int dat_cond_set_storage_key(struct kvm_s390_mmu_cache *mmc, union asce asce, gf return rc; } -int dat_reset_reference_bit(union asce asce, gfn_t gfn) +int dat_reset_reference_bit(union asce asce, gfn_t gfn, union skey *skey) { union pgste pgste, old; union crste *crstep; union pte *ptep; int rc; + skey->skey = 0; + rc = dat_entry_walk(NULL, gfn, asce, DAT_WALK_ANY, TABLE_TYPE_PAGE_TABLE, &crstep, &ptep); if (rc) return rc; @@ -771,21 +773,23 @@ int dat_reset_reference_bit(union asce asce, gfn_t gfn) if (!crste.h.fc || !crste.s.fc1.pr) return 0; - return page_reset_referenced(large_crste_to_phys(*crstep, gfn)); + skey->skey = page_reset_referenced(large_crste_to_phys(*crstep, gfn)) << 1; + return 0; } old = pgste_get_lock(ptep); pgste = old; if (!ptep->h.i) { - rc = page_reset_referenced(pte_origin(*ptep)); - pgste.hr = rc >> 1; + skey->skey = page_reset_referenced(pte_origin(*ptep)) << 1; + pgste.hr = skey->r; } - rc |= (pgste.gr << 1) | pgste.gc; + skey->r |= pgste.gr; + skey->c |= pgste.gc; pgste.gr = 0; dat_update_ptep_sd(old, pgste, ptep); pgste_set_unlock(ptep, pgste); - return rc; + return 0; } static long dat_reset_skeys_pte(union pte *ptep, gfn_t gfn, gfn_t next, struct dat_walk *walk) diff --git a/arch/s390/kvm/dat.h b/arch/s390/kvm/dat.h index fad605305e05..141ee7b9f019 100644 --- a/arch/s390/kvm/dat.h +++ b/arch/s390/kvm/dat.h @@ -537,7 +537,7 @@ int dat_set_storage_key(struct kvm_s390_mmu_cache *mc, union asce asce, gfn_t gf union skey skey, bool nq); int dat_cond_set_storage_key(struct kvm_s390_mmu_cache *mmc, union asce asce, gfn_t gfn, union skey skey, union skey *oldkey, bool nq, bool mr, bool mc); -int dat_reset_reference_bit(union asce asce, gfn_t gfn); +int dat_reset_reference_bit(union asce asce, gfn_t gfn, union skey *skey); long dat_reset_skeys(union asce asce, gfn_t start); unsigned long dat_get_ptval(struct page_table *table, struct ptval_param param); diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 22535f76ae05..efd4042d195b 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -571,7 +571,7 @@ static int kvm_s390_keyop(struct kvm_s390_mmu_cache *mc, struct kvm *kvm, int op switch (op) { case KVM_S390_KEYOP_SSKE: r = dat_cond_set_storage_key(mc, asce, gfn, skey, &skey, 0, 0, 0); - if (r >= 0) + if (r == 0 || r == 1) return skey.skey; break; case KVM_S390_KEYOP_ISKE: @@ -580,14 +580,14 @@ static int kvm_s390_keyop(struct kvm_s390_mmu_cache *mc, struct kvm *kvm, int op return skey.skey; break; case KVM_S390_KEYOP_RRBE: - r = dat_reset_reference_bit(asce, gfn); - if (r > 0) - return r << 1; + r = dat_reset_reference_bit(asce, gfn, &skey); + if (!r) + return skey.skey; break; default: return -EINVAL; } - return r; + return r > 0 ? -EFAULT : r; } /* Section: device related */ @@ -2214,7 +2214,7 @@ static int kvm_s390_get_skeys(struct kvm *kvm, struct kvm_s390_skeys *args) } kvfree(keys); - return r; + return r <= 0 ? r : -EFAULT; } static int kvm_s390_set_skeys(struct kvm *kvm, struct kvm_s390_skeys *args) @@ -2276,7 +2276,7 @@ static int kvm_s390_set_skeys(struct kvm *kvm, struct kvm_s390_skeys *args) kvm_s390_free_mmu_cache(mc); out: kvfree(keys); - return r; + return r <= 0 ? r : -EFAULT; } /* @@ -2386,7 +2386,7 @@ static int kvm_s390_set_cmma_bits(struct kvm *kvm, set_bit(GMAP_FLAG_USES_CMM, &kvm->arch.gmap->flags); - return r; + return r <= 0 ? r : -EFAULT; } /** diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c index ad0ddc433a73..ea5a99537346 100644 --- a/arch/s390/kvm/priv.c +++ b/arch/s390/kvm/priv.c @@ -289,6 +289,7 @@ static int handle_iske(struct kvm_vcpu *vcpu) static int handle_rrbe(struct kvm_vcpu *vcpu) { unsigned long gaddr; + union skey skey; int reg1, reg2; int rc; @@ -307,12 +308,12 @@ static int handle_rrbe(struct kvm_vcpu *vcpu) gaddr = kvm_s390_logical_to_effective(vcpu, gaddr); gaddr = kvm_s390_real_to_abs(vcpu, gaddr); scoped_guard(read_lock, &vcpu->kvm->mmu_lock) - rc = dat_reset_reference_bit(vcpu->arch.gmap->asce, gpa_to_gfn(gaddr)); + rc = dat_reset_reference_bit(vcpu->arch.gmap->asce, gpa_to_gfn(gaddr), &skey); if (rc > 0) return kvm_s390_inject_program_int(vcpu, rc); if (rc < 0) return rc; - kvm_s390_set_psw_cc(vcpu, rc); + kvm_s390_set_psw_cc(vcpu, (skey.skey >> 1) & 3); return 0; } -- 2.55.0