From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roger Pau =?utf-8?B?TW9ubsOp?= Subject: Re: [PATCH v4 2/2] xen/blkback: rework connect_ring() to avoid inconsistent xenstore 'ring-page-order' set by malicious blkfront Date: Mon, 7 Jan 2019 16:27:08 +0100 Message-ID: <20190107152708.z4mecdm2apfxz2rk__41919.1009401858$1546874819$gmane$org@mac> References: <1546839359-5478-1-git-send-email-dongli.zhang@oracle.com> <1546839359-5478-2-git-send-email-dongli.zhang@oracle.com> <20190107120107.euf7mrq7gk6bmibz@mac> <35c7d495-2d6c-5fec-abf8-c5aef55cf866@oracle.com> <56819579-def2-b045-f414-4de45188fe2e@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1ggWoj-0006pk-Jh for xen-devel@lists.xenproject.org; Mon, 07 Jan 2019 15:27:53 +0000 Content-Disposition: inline In-Reply-To: <56819579-def2-b045-f414-4de45188fe2e@oracle.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" To: Dongli Zhang Cc: axboe@kernel.dk, konrad.wilk@oracle.com, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, Paul.Durrant@citrix.com, xen-devel@lists.xenproject.org List-Id: xen-devel@lists.xenproject.org T24gTW9uLCBKYW4gMDcsIDIwMTkgYXQgMTA6MDc6MzRQTSArMDgwMCwgRG9uZ2xpIFpoYW5nIHdy b3RlOgo+IAo+IAo+IE9uIDAxLzA3LzIwMTkgMTA6MDUgUE0sIERvbmdsaSBaaGFuZyB3cm90ZToK PiA+IAo+ID4gCj4gPiBPbiAwMS8wNy8yMDE5IDA4OjAxIFBNLCBSb2dlciBQYXUgTW9ubsOpIHdy b3RlOgo+ID4+IE9uIE1vbiwgSmFuIDA3LCAyMDE5IGF0IDAxOjM1OjU5UE0gKzA4MDAsIERvbmds aSBaaGFuZyB3cm90ZToKPiA+Pj4gVGhlIHhlbnN0b3JlICdyaW5nLXBhZ2Utb3JkZXInIGlzIHVz ZWQgZ2xvYmFsbHkgZm9yIGVhY2ggYmxrYmFjayBxdWV1ZSBhbmQKPiA+Pj4gdGhlcmVmb3JlIHNo b3VsZCBiZSByZWFkIGZyb20geGVuc3RvcmUgb25seSBvbmNlLiBIb3dldmVyLCBpdCBpcyBvYnRh aW5lZAo+ID4+PiBpbiByZWFkX3Blcl9yaW5nX3JlZnMoKSB3aGljaCBtaWdodCBiZSBjYWxsZWQg bXVsdGlwbGUgdGltZXMgZHVyaW5nIHRoZQo+ID4+PiBpbml0aWFsaXphdGlvbiBvZiBlYWNoIGJs a2JhY2sgcXVldWUuCj4gPj4+Cj4gPj4+IElmIHRoZSBibGtmcm9udCBpcyBtYWxpY2lvdXMgYW5k IHRoZSAncmluZy1wYWdlLW9yZGVyJyBpcyBzZXQgaW4gZGlmZmVyZW50Cj4gPj4+IHZhbHVlIGJ5 IGJsa2Zyb250IGV2ZXJ5IHRpbWUgYmVmb3JlIGJsa2JhY2sgcmVhZHMgaXQsIHRoaXMgbWF5IGVu ZCB1cCBhdAo+ID4+PiB0aGUgIldBUk5fT04oaSAhPSAoWEVOX0JMS0lGX1JFUVNfUEVSX1BBR0Ug KiBibGtpZi0+bnJfcmluZ19wYWdlcykpOyIgaW4KPiA+Pj4geGVuX2Jsa2lmX2Rpc2Nvbm5lY3Qo KSB3aGVuIGZyb250ZW5kIGlzIGRlc3Ryb3llZC4KPiA+Pj4KPiA+Pj4gVGhpcyBwYXRjaCByZXdv cmtzIGNvbm5lY3RfcmluZygpIHRvIHJlYWQgeGVuc3RvcmUgJ3JpbmctcGFnZS1vcmRlcicgb25s eQo+ID4+PiBvbmNlLgo+ID4+Pgo+ID4+PiBTaWduZWQtb2ZmLWJ5OiBEb25nbGkgWmhhbmcgPGRv bmdsaS56aGFuZ0BvcmFjbGUuY29tPgo+ID4+PiAtLS0KPiA+Pj4gQ2hhbmdlZCBzaW5jZSB2MToK PiA+Pj4gICAqIGNoYW5nZSB0aGUgb3JkZXIgb2YgeGVuc3RvcmUgcmVhZCBpbiByZWFkX3Blcl9y aW5nX3JlZnMKPiA+Pj4gICAqIHVzZSB4ZW5idXNfcmVhZF91bnNpZ25lZCgpIGluIGNvbm5lY3Rf cmluZygpCj4gPj4+Cj4gPj4+IENoYW5nZWQgc2luY2UgdjI6Cj4gPj4+ICAgKiBzaW1wbGlmeSB0 aGUgY29uZGl0aW9uIGNoZWNrIGFzICIoZXJyICE9IDEgJiYgbnJfZ3JlZnMgPiAxKSIKPiA+Pj4g ICAqIGF2b2lkIHNldHRpbmcgZXJyIGFzIC1FSU5WQUwgdG8gcmVtb3ZlIGV4dHJhIG9uZSBsaW5l IG9mIGNvZGUKPiA+Pj4KPiA+Pj4gQ2hhbmdlZCBzaW5jZSB2MzoKPiA+Pj4gICAqIGV4aXQgYXQg dGhlIGJlZ2lubmluZyBpZiAhbnJfZ3JlZnMKPiA+Pj4gICAqIGNoYW5nZSB0aGUgaWYgc3RhdGVt ZW50cyB0byBhdm9pZCB0ZXN0IChlcnIgIT0gMSkgdHdpY2UKPiA+Pj4gICAqIGluaXRpYWxpemUg YSAnYmxraWYnIHN0YWNrIHZhcmlhYmxlIChyZWZlciB0byBQQVRDSCAxLzIpCj4gPj4+Cj4gPj4+ ICBkcml2ZXJzL2Jsb2NrL3hlbi1ibGtiYWNrL3hlbmJ1cy5jIHwgNzYgKysrKysrKysrKysrKysr KysrKysrLS0tLS0tLS0tLS0tLS0tLS0KPiA+Pj4gIDEgZmlsZSBjaGFuZ2VkLCA0MyBpbnNlcnRp b25zKCspLCAzMyBkZWxldGlvbnMoLSkKPiA+Pj4KPiA+Pj4gZGlmZiAtLWdpdCBhL2RyaXZlcnMv YmxvY2sveGVuLWJsa2JhY2sveGVuYnVzLmMgYi9kcml2ZXJzL2Jsb2NrL3hlbi1ibGtiYWNrL3hl bmJ1cy5jCj4gPj4+IGluZGV4IGE0YWFkYWMuLmEyYWNiYzkgMTAwNjQ0Cj4gPj4+IC0tLSBhL2Ry aXZlcnMvYmxvY2sveGVuLWJsa2JhY2sveGVuYnVzLmMKPiA+Pj4gKysrIGIvZHJpdmVycy9ibG9j ay94ZW4tYmxrYmFjay94ZW5idXMuYwo+ID4+PiBAQCAtOTI2LDcgKzkyNiw3IEBAIHN0YXRpYyBp bnQgcmVhZF9wZXJfcmluZ19yZWZzKHN0cnVjdCB4ZW5fYmxraWZfcmluZyAqcmluZywgY29uc3Qg Y2hhciAqZGlyKQo+ID4+PiAgCWludCBlcnIsIGksIGo7Cj4gPj4+ICAJc3RydWN0IHhlbl9ibGtp ZiAqYmxraWYgPSByaW5nLT5ibGtpZjsKPiA+Pj4gIAlzdHJ1Y3QgeGVuYnVzX2RldmljZSAqZGV2 ID0gYmxraWYtPmJlLT5kZXY7Cj4gPj4+IC0JdW5zaWduZWQgaW50IHJpbmdfcGFnZV9vcmRlciwg bnJfZ3JlZnMsIGV2dGNobjsKPiA+Pj4gKwl1bnNpZ25lZCBpbnQgbnJfZ3JlZnMsIGV2dGNobjsK PiA+Pj4gIAo+ID4+PiAgCWVyciA9IHhlbmJ1c19zY2FuZihYQlRfTklMLCBkaXIsICJldmVudC1j aGFubmVsIiwgIiV1IiwKPiA+Pj4gIAkJCSAgJmV2dGNobik7Cj4gPj4+IEBAIC05MzYsNDMgKzkz NiwzOCBAQCBzdGF0aWMgaW50IHJlYWRfcGVyX3JpbmdfcmVmcyhzdHJ1Y3QgeGVuX2Jsa2lmX3Jp bmcgKnJpbmcsIGNvbnN0IGNoYXIgKmRpcikKPiA+Pj4gIAkJcmV0dXJuIGVycjsKPiA+Pj4gIAl9 Cj4gPj4+ICAKPiA+Pj4gLQllcnIgPSB4ZW5idXNfc2NhbmYoWEJUX05JTCwgZGV2LT5vdGhlcmVu ZCwgInJpbmctcGFnZS1vcmRlciIsICIldSIsCj4gPj4+IC0JCQkgICZyaW5nX3BhZ2Vfb3JkZXIp Owo+ID4+PiAtCWlmIChlcnIgIT0gMSkgewo+ID4+PiAtCQllcnIgPSB4ZW5idXNfc2NhbmYoWEJU X05JTCwgZGlyLCAicmluZy1yZWYiLCAiJXUiLCAmcmluZ19yZWZbMF0pOwo+ID4+PiArCW5yX2dy ZWZzID0gYmxraWYtPm5yX3JpbmdfcGFnZXM7Cj4gPj4+ICsKPiA+Pj4gKwlpZiAodW5saWtlbHko IW5yX2dyZWZzKSkKPiA+Pj4gKwkJcmV0dXJuIC1FSU5WQUw7Cj4gPj4KPiA+PiBJcyB0aGlzIGV2 ZW4gcG9zc2libGU/IEFGQUlDVCByZWFkX3Blcl9yaW5nX3JlZnMgd2lsbCBhbHdheXMgYmUgY2Fs bGVkCj4gPj4gd2l0aCBibGtpZi0+bnJfcmluZ19wYWdlcyAhPSAwPwo+ID4+Cj4gPj4gSWYgc28s IEkgd291bGQgY29uc2lkZXIgdHVybmluZyB0aGlzIGludG8gYSBCVUdfT04vV0FSTl9PTi4KPiA+ IAo+ID4gSXQgdXNlZCB0byBiZSAiV0FSTl9PTighbnJfZ3JlZnMpOyIgaW4gdGhlIHYzIG9mIHRo ZSBwYXRjaC4KPiA+IAo+ID4gSSB3b3VsZCB0dXJuIGl0IGludG8gV0FSTl9PTiBpZiBpdCBpcyBm aW5lIHdpdGggYm90aCBQYXVsIGFuZCB5b3UuCj4gCj4gVG8gY2xhcmlmeSwgSSB3b3VsZCB1c2Ug V0FSTl9PTigpIGJlZm9yZSBleGl0IHdpdGggLUVJTlZBTCAod2hlbgo+IGJsa2lmLT5ucl9yaW5n X3BhZ2VzIGlzIDApLgoKR2l2ZW4gdGhhdCB0aGlzIGZ1bmN0aW9uIHdpbGwgbmV2ZXIgYmUgY2Fs bGVkIHdpdGggbnJfcmluZ19wYWdlcyA9PSAwCkkgd291bGQgYmUgZmluZSB3aXRoIGp1c3QgdXNp bmcgYSBCVUdfT04sIGdldHRpbmcgaGVyZSB3aXRoCm5yX3JpbmdfcGFnZXMgPT0gMCB3b3VsZCBp bXBseSBtZW1vcnkgY29ycnVwdGlvbiBvciBzb21lIG90aGVyIHNldmVyZQppc3N1ZSBoYXMgaGFw cGVuZWQsIGFuZCB0aGVyZSdzIG5vIHBvc3NpYmxlIHJlY292ZXJ5LgoKSWYgeW91IHdhbnQgdG8g aW5zdGVhZCBrZWVwIHRoZSByZXR1cm4sIHBsZWFzZSB1c2UgcGxhaW4gV0FSTiBpbnN0ZWFkCm9m IFdBUk5fT04uCgpUaGFua3MsIFJvZ2VyLgoKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX18KWGVuLWRldmVsIG1haWxpbmcgbGlzdApYZW4tZGV2ZWxAbGlzdHMu eGVucHJvamVjdC5vcmcKaHR0cHM6Ly9saXN0cy54ZW5wcm9qZWN0Lm9yZy9tYWlsbWFuL2xpc3Rp bmZvL3hlbi1kZXZlbA==