From mboxrd@z Thu Jan 1 00:00:00 1970 From: Waiman Long Subject: [PATCH-block v3 1/2] bdi, blk-cgroup: Fix potential UAF of blkcg Date: Tue, 13 Dec 2022 13:44:45 -0500 Message-ID: <20221213184446.50181-2-longman@redhat.com> References: <20221213184446.50181-1-longman@redhat.com> Mime-Version: 1.0 Content-Transfer-Encoding: base64 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1670957103; 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=XKtEb7DX5sCj2p62DhFAWIKVGv8SYAUBUDgGPKa8O/0=; b=Q822aMYKwgls0VAuvvolUQeg/XGipJ3aWV0MZNsRmg6x3024yiDgP+uyOtZc1YwP1ec8fC iRNDixTQaVbuPv6/noR/JLKX7hObjMVaweS0f4a5dvZy7SBLPUHJbk2tp0zAdLGpoQu9Qo D0qPLESQvrKMfbZt98HQ5Uwi/WZsPnk= In-Reply-To: <20221213184446.50181-1-longman@redhat.com> List-ID: Content-Type: text/plain; charset="macroman" To: Jens Axboe , Tejun Heo , Josef Bacik , Zefan Li , Johannes Weiner , Andrew Morton Cc: cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, =?UTF-8?q?Michal=20Koutn=C3=BD?= , "Dennis Zhou (Facebook)" , Waiman Long , Yi Zhang Q29tbWl0IDU5YjU3NzE3ZmZmOCAoImJsa2NnOiBkZWxheSBibGtnIGRlc3RydWN0aW9uIHVudGls IGFmdGVyCndyaXRlYmFjayBoYXMgZmluaXNoZWQiKSBkZWxheWVkIGNhbGwgdG8gYmxrY2dfZGVz dHJveV9ibGtncygpIHRvCmNnd2JfcmVsZWFzZV93b3JrZm4oKS4gSG93ZXZlciwgaXQgaXMgZG9u ZSBhZnRlciBhIGNzc19wdXQoKSBvZiBibGtjZwp3aGljaCBtYXkgYmUgdGhlIGZpbmFsIHB1dCB0 aGF0IGNhdXNlcyB0aGUgYmxrY2cgdG8gYmUgZnJlZWQgYXMgUkNVCnJlYWQgbG9jayBpc24ndCBo ZWxkLgoKQW5vdGhlciBwbGFjZSB3aGVyZSBibGtjZ19kZXN0cm95X2Jsa2dzKCkgY2FuIGJlIGNh bGxlZCBpbmRpcmVjdGx5IHZpYQpibGtjZ191bnBpbl9vbmxpbmUoKSBpcyBmcm9tIHRoZSBvZmZs aW5lX2NzcygpIGZ1bmN0aW9uIGNhbGxlZCBmcm9tCmNzc19raWxsZWRfd29ya19mbigpLiBPdmVy IHRoZXJlLCB0aGUgcG90ZW50aWFsbHkgZmluYWwgY3NzX3B1dCgpIGNhbGwKaXMgaXNzdWVkIGFm dGVyIG9mZmxpbmVfY3NzKCkuCgpCeSBhZGRpbmcgYSBjc3NfdHJ5Z2V0KCkgaW50byBibGtjZ19k ZXN0cm95X2Jsa2dzKCkgYW5kIHdhcm5pbmcgaXRzCmZhaWx1cmUsIHRoZSBmb2xsb3dpbmcgc3Rh Y2sgdHJhY2Ugd2FzIHByb2R1Y2VkIGluIGEgdGVzdCBzeXN0ZW0gb24KYm9vdHVwLgoKWyAgIDM0 LjI1NDI0MF0gUklQOiAwMDEwOmJsa2NnX2Rlc3Ryb3lfYmxrZ3MrMHgxNmEvMHgxYTAKICAgICAg OgpbICAgMzQuMzM5OTQzXSBDYWxsIFRyYWNlOgpbICAgMzQuMzQ0NTEwXSAgYmxrY2dfdW5waW5f b25saW5lKzB4MzgvMHg2MApbICAgMzQuMzQ4NTIzXSAgY2d3Yl9yZWxlYXNlX3dvcmtmbisweDZh LzB4MjAwClsgICAzNC4zNTI3MDhdICBwcm9jZXNzX29uZV93b3JrKzB4MWU1LzB4M2IwClsgICAz NC4zNjA3NThdICB3b3JrZXJfdGhyZWFkKzB4NTAvMHgzYTAKWyAgIDM0LjM2ODQ0N10gIGt0aHJl YWQrMHhkOS8weDEwMApbICAgMzQuMzc2Mzg2XSAgcmV0X2Zyb21fZm9yaysweDIyLzB4MzAKClRo aXMgY29uZmlybXMgdGhhdCBhIHBvdGVudGlhbCBVQUYgc2l0dWF0aW9uIGNhbiByZWFsbHkgaGFw cGVuIGluCmNnd2JfcmVsZWFzZV93b3JrZm4oKS4KCkZpeCB0aGF0IGJ5IGRlbGF5aW5nIHRoZSBj c3NfcHV0KCkgdW50aWwgYWZ0ZXIgdGhlIGJsa2NnX3VucGluX29ubGluZSgpCmNhbGwuIEFsc28g dXNlIGNzc190cnlnZXQoKSBpbiBibGtjZ19kZXN0cm95X2Jsa2dzKCkgYW5kIGlzc3VlIGEgd2Fy bmluZwppZiBjc3NfdHJ5Z2V0KCkgZmFpbHMuCgpUaGUgcmVwcm9kdWNpbmcgc3lzdGVtIGNhbiBu byBsb25nZXIgcHJvZHVjZSBhIHdhcm5pbmcgd2l0aCB0aGlzIHBhdGNoLgpBbGwgdGhlIHJ1bm5h YmxlIGJsb2NrLzAqIHRlc3RzIGluY2x1ZGluZyBibG9jay8wMjcgd2VyZSBydW4gc3VjY2Vzc2Z1 bGx5CndpdGhvdXQgZmFpbHVyZS4KCkZpeGVzOiA1OWI1NzcxN2ZmZjggKCJibGtjZzogZGVsYXkg YmxrZyBkZXN0cnVjdGlvbiB1bnRpbCBhZnRlciB3cml0ZWJhY2sgaGFzIGZpbmlzaGVkIikKU3Vn Z2VzdGVkLWJ5OiBNaWNoYWwgS291dG7DvSA8bWtvdXRueUBzdXNlLmNvbT4KUmVwb3J0ZWQtYnk6 IFlpIFpoYW5nIDx5aS56aGFuZ0ByZWRoYXQuY29tPgpTaWduZWQtb2ZmLWJ5OiBXYWltYW4gTG9u ZyA8bG9uZ21hbkByZWRoYXQuY29tPgotLS0KIGJsb2NrL2Jsay1jZ3JvdXAuYyB8IDcgKysrKysr KwogbW0vYmFja2luZy1kZXYuYyAgIHwgOCArKysrKystLQogMiBmaWxlcyBjaGFuZ2VkLCAxMyBp bnNlcnRpb25zKCspLCAyIGRlbGV0aW9ucygtKQoKZGlmZiAtLWdpdCBhL2Jsb2NrL2Jsay1jZ3Jv dXAuYyBiL2Jsb2NrL2Jsay1jZ3JvdXAuYwppbmRleCAxYmI5MzlkM2I3OTMuLmNhMjgzMDZhYTFi MSAxMDA2NDQKLS0tIGEvYmxvY2svYmxrLWNncm91cC5jCisrKyBiL2Jsb2NrL2Jsay1jZ3JvdXAu YwpAQCAtMTA4NCw2ICsxMDg0LDEzIEBAIHN0cnVjdCBsaXN0X2hlYWQgKmJsa2NnX2dldF9jZ3di X2xpc3Qoc3RydWN0IGNncm91cF9zdWJzeXNfc3RhdGUgKmNzcykKICAqLwogc3RhdGljIHZvaWQg YmxrY2dfZGVzdHJveV9ibGtncyhzdHJ1Y3QgYmxrY2cgKmJsa2NnKQogeworCS8qCisJICogYmxr Y2dfZGVzdHJveV9ibGtncygpIHNob3VsZG4ndCBiZSBjYWxsZWQgd2l0aCBhbGwgdGhlIGJsa2Nn CisJICogcmVmZXJlbmNlcyBnb25lLgorCSAqLworCWlmIChXQVJOX09OX09OQ0UocGVyY3B1X3Jl Zl9pc196ZXJvKCZibGtjZy0+Y3NzLnJlZmNudCkpKQorCQlyZXR1cm47CisKIAltaWdodF9zbGVl cCgpOwogCiAJc3Bpbl9sb2NrX2lycSgmYmxrY2ctPmxvY2spOwpkaWZmIC0tZ2l0IGEvbW0vYmFj a2luZy1kZXYuYyBiL21tL2JhY2tpbmctZGV2LmMKaW5kZXggYzMwNDE5YTVlMTE5Li4zNmY3NWIw NzIzMjUgMTAwNjQ0Ci0tLSBhL21tL2JhY2tpbmctZGV2LmMKKysrIGIvbW0vYmFja2luZy1kZXYu YwpAQCAtMzkwLDExICszOTAsMTUgQEAgc3RhdGljIHZvaWQgY2d3Yl9yZWxlYXNlX3dvcmtmbihz dHJ1Y3Qgd29ya19zdHJ1Y3QgKndvcmspCiAJd2Jfc2h1dGRvd24od2IpOwogCiAJY3NzX3B1dCh3 Yi0+bWVtY2dfY3NzKTsKLQljc3NfcHV0KHdiLT5ibGtjZ19jc3MpOwogCW11dGV4X3VubG9jaygm d2ItPmJkaS0+Y2d3Yl9yZWxlYXNlX211dGV4KTsKIAotCS8qIHRyaWdnZXJzIGJsa2cgZGVzdHJ1 Y3Rpb24gaWYgbm8gb25saW5lIHVzZXJzIGxlZnQgKi8KKwkvKgorCSAqIFRyaWdnZXJzIGJsa2cg ZGVzdHJ1Y3Rpb24gaWYgbm8gb25saW5lIHVzZXJzIGxlZnQKKwkgKiBUaGUgZmluYWwgYmxrY2cg Y3NzX3B1dCgpIGhhcyB0byBiZSBkb25lIGFmdGVyIGJsa2NnX3VucGluX29ubGluZSgpCisJICog dG8gYXZvaWQgdXNlLWFmdGVyLWZyZWUuCisJICovCiAJYmxrY2dfdW5waW5fb25saW5lKHdiLT5i bGtjZ19jc3MpOworCWNzc19wdXQod2ItPmJsa2NnX2Nzcyk7CiAKIAlmcHJvcF9sb2NhbF9kZXN0 cm95X3BlcmNwdSgmd2ItPm1lbWNnX2NvbXBsZXRpb25zKTsKIAotLSAKMi4zMS4xCgo=