From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=170.10.129.124 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793641528; b=PvxDJnnaPvC5/u1V522OyHgL2o+Hn7BWWZp9GfOtN2J//LH7Y9s32CA2YdgcHGIjFYuX 7SaD/mamfgrd+0yB/093wqWMSnNIyuZIQKEl7yCjRb5fceROFy55zNr5TpCvjoqhwwKlB c2kLKtAwQyeSSb8r34Y6NEAY5NnqSPWfFF57jdPGvbFBuRuaaVTMIaYsmTKYrnx1HC8no bmfUmqw4r3Fb6soJ9SWA20kAzHzaZsF1xqUjLlbF66oQY7GNPPC8WORtwuwt0wfM8IqHo g0dBdfiERkz4v24vi7ioNeUxfORA68f6MbprVf2uGX0EJA2Chnxyk4kaAPanECAurGg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793641528; h=DMARC-Filter:DKIM-Signature:Received:X-MC-Unique: X-Mimecast-MFC-AGG-ID:Received:Received:From:To:Cc:Subject:Date: Message-ID:In-Reply-To:References:MIME-Version:Content-Type: Content-Transfer-Encoding:X-Scanned-By; bh=PYwT8C8YBZBl9jtyu1J67hJllZibYxUPZTWxJc2Safw=; b=ggcFenpkLjesaIAvQGigMdSfhvUpN7jCWuxJow1eIMjmtbyvx/TZKSo1leZJh/HDzwB4 vNe8QlL714qjdBRdy2jGftA6ARjnw4S3s1IGKKxUIx0PCYFIBFoTqllGyPTeoI8uc7ZLV DQIj/6ixKgiZGmUR8/F2yb1ke9I7w5c6Sv5qHXxXq4ImW4h/9cuyv/2DQGS1UfIYcYNw3 ox36Zhma70GWUbV00sDkog7XFcFMQzJSJC3Ev4s9YX4Ry3wMPeOdiaxX8gqPIf6nNOd+2 Ph854j/wMMRwa+HG+XMGKA6wuuVjlwcKgBYXeNfySLswpGTwxnq/s0zKPaLl23MvWBA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=DXzhGS6M; arc=none smtp.remote-ip=170.10.129.124 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E787B60A5BC4 for ; Mon, 2 Nov 2026 17:45:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org E787B60A5BC4 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=DXzhGS6M DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1793641527; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=PYwT8C8YBZBl9jtyu1J67hJllZibYxUPZTWxJc2Safw=; b=DXzhGS6MlzUfEPNRh7iylntAbvAbneJRKlnHohDc8T0LDQoXVIJzdPcc37E528QezjVX1V DZx48vfVfWyGUKonUO1pL5grd78N1W1ak7/qOzH1dvPtf7NypKQDgG6KQNnDRjlYm0REe1 oFx9Yw/eOGAonpJ0RxJBmrjytlSeXWk= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-633-pBdrkj1hOIKS-YLizBpQGg-1; Mon, 02 Nov 2026 12:45:22 -0500 X-MC-Unique: pBdrkj1hOIKS-YLizBpQGg-1 X-Mimecast-MFC-AGG-ID: pBdrkj1hOIKS-YLizBpQGg_1793641522 Received: from mx-prod-int-10.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-10.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.95]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id DA4D0195606D; Mon, 2 Nov 2026 17:45:21 +0000 (UTC) Received: from virtlab1023.virt.eng.rdu2.dc.redhat.com (virtlab1023.virt.eng.rdu2.dc.redhat.com [10.18.48.26]) by mx-prod-int-10.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 68356433; Mon, 2 Nov 2026 17:45:21 +0000 (UTC) From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Nicolas Saenz Julienne Subject: [PATCH 29/45] KVM: x86/emulate: change return value of emulator_io_permitted to int Date: Mon, 2 Nov 2026 12:44:56 -0500 Message-ID: <20261102174512.8903-13-pbonzini@redhat.com> In-Reply-To: <20261102174130.8779-1-pbonzini@redhat.com> References: <20261102174130.8779-1-pbonzini@redhat.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.6 on 10.30.177.95 Allow emulator_io_permitted to distinguish memory attribute faults from disallowed I/O ports. Signed-off-by: Paolo Bonzini --- arch/x86/kvm/emulate.c | 50 +++++++++++++++++++++++++----------------- 1 file changed, 30 insertions(+), 20 deletions(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 711794592c2c..8464816349b5 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -2526,8 +2526,8 @@ static bool emulator_bad_iopl(struct x86_emulate_ctxt *ctxt) #define VMWARE_PORT_VMPORT (0x5658) #define VMWARE_PORT_VMRPC (0x5659) -static bool emulator_io_port_access_allowed(struct x86_emulate_ctxt *ctxt, - u16 port, u16 len) +static int emulator_io_port_access_allowed(struct x86_emulate_ctxt *ctxt, + u16 port, u16 len) { const struct x86_emulate_ops *ops = ctxt->ops; struct desc_struct tr_seg; @@ -2543,43 +2543,47 @@ static bool emulator_io_port_access_allowed(struct x86_emulate_ctxt *ctxt, */ if (enable_vmware_backdoor && ((port == VMWARE_PORT_VMPORT) || (port == VMWARE_PORT_VMRPC))) - return true; + return 0; ops->get_segment(ctxt, &tr, &tr_seg, &base3, VCPU_SREG_TR); if (!tr_seg.p) - return false; + return -EACCES; if (desc_limit_scaled(&tr_seg) < 103) - return false; + return -EACCES; base = get_desc_base(&tr_seg); #ifdef CONFIG_X86_64 base |= ((u64)base3) << 32; #endif r = ops->read_std(ctxt, base + 102, &io_bitmap_ptr, 2, NULL, true); if (r != X86EMUL_CONTINUE) - return false; + return -EACCES; if (io_bitmap_ptr + port/8 > desc_limit_scaled(&tr_seg)) - return false; + return -EACCES; r = ops->read_std(ctxt, base + io_bitmap_ptr + port/8, &perm, 2, NULL, true); if (r != X86EMUL_CONTINUE) - return false; + return -EACCES; if ((perm >> bit_idx) & mask) - return false; - return true; + return -EACCES; + return 0; } -static bool emulator_io_permitted(struct x86_emulate_ctxt *ctxt, - u16 port, u16 len) +static int emulator_io_permitted(struct x86_emulate_ctxt *ctxt, + u16 port, u16 len) { - if (ctxt->perm_ok) - return true; + int r; - if (emulator_bad_iopl(ctxt)) - if (!emulator_io_port_access_allowed(ctxt, port, len)) - return false; + if (ctxt->perm_ok) + return 0; + + if (emulator_bad_iopl(ctxt)) { + r = emulator_io_port_access_allowed(ctxt, port, len); + if (r) + return r; + } ctxt->perm_ok = true; - return true; + return 0; } static void string_registers_quirk(struct x86_emulate_ctxt *ctxt) @@ -3931,8 +3935,11 @@ static int check_rdpmc(struct x86_emulate_ctxt *ctxt) static int check_perm_in(struct x86_emulate_ctxt *ctxt) { + int r; + ctxt->dst.bytes = min(ctxt->dst.bytes, 4u); - if (!emulator_io_permitted(ctxt, ctxt->src.val, ctxt->dst.bytes)) + r = emulator_io_permitted(ctxt, ctxt->src.val, ctxt->dst.bytes); + if (r) return emulate_gp(ctxt, 0); return X86EMUL_CONTINUE; @@ -3940,8 +3947,11 @@ static int check_perm_in(struct x86_emulate_ctxt *ctxt) static int check_perm_out(struct x86_emulate_ctxt *ctxt) { + int r; + ctxt->src.bytes = min(ctxt->src.bytes, 4u); - if (!emulator_io_permitted(ctxt, ctxt->dst.val, ctxt->src.bytes)) + r = emulator_io_permitted(ctxt, ctxt->dst.val, ctxt->src.bytes); + if (r) return emulate_gp(ctxt, 0); return X86EMUL_CONTINUE; -- 2.52.0